don't show hardware S-RAM value on HUD in debug

[taylor/freespace2.git] / src / graphics / gropengl.cpp

/*
 * Copyright (C) Volition, Inc. 1999.  All rights reserved.
 *
 * All source code herein is the property of Volition, Inc. You may not sell 
 * or otherwise commercially exploit the source or things you created based on
 * the source.
 */

/*
 * $Logfile: /Freespace2/code/Graphics/GrOpenGL.cpp $
 * $Revision$
 * $Date$
 * $Author$
 *
 * Code that uses the OpenGL graphics library
 *
 * $Log$
 * Revision 1.74  2005/08/12 08:57:20  taylor
 * don't show hardware S-RAM value on HUD in debug
 * do show in use GL texture memory
 * have an actual fade effect for the credits screen artwork
 *
 * Revision 1.73  2005/04/02 18:58:08  taylor
 * attempt to fix garbage at end of GL extension string
 *
 * Revision 1.72  2005/03/30 01:20:12  taylor
 * Screenshot function filled, will output into ~/.freespace(2)/Data
 * Use glTexSubImage2D on reloaded texture slots, this is only used by ANIs
 *
 * Revision 1.71  2004/12/15 04:10:45  taylor
 * outwnd_unix.cpp from fs2_open for logging to file in debug mode
 * fixes for default function values
 * always use vm_* functions for sanity sake
 * make cfilearchiver 64-bit compatible
 * fix crash on exit from double free()
 * fix crash on startup from extra long GL extension string in debug
 *
 * Revision 1.70  2004/09/20 01:31:44  theoddone33
 * GCC 3.4 fixes.
 *
 * Revision 1.69  2004/07/04 11:31:43  taylor
 * amd64 support, compiler warning fixes, don't use software rendering
 *
 * Revision 1.68  2004/06/11 01:01:07  tigital
 * added FSAA support: switched on in .ini
 *
 * Revision 1.67  2003/08/03 15:59:40  taylor
 * GL_RGB5_A1 as TexImage internal format; cleaner input grab; min window title; cleanup
 *
 * Revision 1.66  2003/06/22 12:52:34  taylor
 * more texture size fixin
 *
 * Revision 1.65  2003/06/19 11:52:47  taylor
 * fix texture size issue with lower detail settings
 *
 * Revision 1.64  2003/05/28 06:02:04  taylor
 * fix transparency in green weapon blobs
 *
 * Revision 1.63  2003/05/09 05:05:52  taylor
 * improve gr_(de)activate, mouse grab, default fullscreen
 *
 * Revision 1.62  2003/05/04 04:56:53  taylor
 * move SDL_Quit to os_deinit to fix fonttool segfault
 *
 * Revision 1.61  2003/02/02 21:13:27  relnev
 * minor updates (made functions static, tried to improve texture sizes)
 *
 * Revision 1.60  2003/02/02 20:20:03  relnev
 * add large texture support (Taylor Richards)
 *
 * Revision 1.59  2002/09/04 01:38:09  relnev
 * revert
 *
 * Revision 1.57  2002/08/31 01:39:13  theoddone33
 * Speed up the renderer a tad
 *
 * Revision 1.56  2002/08/01 05:03:11  relnev
 * minor change
 *
 * Revision 1.55  2002/08/01 04:55:45  relnev
 * experimenting with texture state
 *
 * Revision 1.54  2002/07/30 15:00:15  relnev
 * not use luminance alpha by default
 *
 * Revision 1.53  2002/06/22 17:08:16  relnev
 * more fixes to unused alpha code
 *
 * Revision 1.52  2002/06/21 23:59:14  relnev
 * moved a gr_opengl_set_state to after the gr_tcache_set
 *
 * Revision 1.51  2002/06/19 04:52:45  relnev
 * MacOS X updates (Ryan)
 *
 * Revision 1.50  2002/06/18 23:20:44  relnev
 * fixed _splitpath.
 *
 * adjusted line offsets.
 *
 * Revision 1.49  2002/06/17 23:11:39  relnev
 * enable sdl key repeating.
 *
 * swap '/` keys.
 *
 * Revision 1.48  2002/06/09 04:41:17  relnev
 * added copyright header
 *
 * Revision 1.47  2002/06/09 03:16:04  relnev
 * added _splitpath.
 *
 * removed unneeded asm, old sdl 2d setup.
 *
 * fixed crash caused by opengl_get_region.
 *
 * Revision 1.46  2002/06/05 04:03:32  relnev
 * finished cfilesystem.
 *
 * removed some old code.
 *
 * fixed mouse save off-by-one.
 *
 * sound cleanups.
 *
 * Revision 1.45  2002/06/03 09:25:37  relnev
 * implement mouse cursor and screen save/restore
 *
 * Revision 1.44  2002/06/02 18:46:59  relnev
 * updated
 *
 * Revision 1.43  2002/06/02 11:34:00  relnev
 * adjust z coords
 *
 * Revision 1.42  2002/06/02 10:28:17  relnev
 * fix texture handle leak
 *
 * Revision 1.41  2002/06/01 09:00:34  relnev
 * silly debug memmanager
 *
 * Revision 1.40  2002/06/01 07:12:33  relnev
 * a few NDEBUG updates.
 *
 * removed a few warnings.
 *
 * Revision 1.39  2002/06/01 05:33:15  relnev
 * copied more code over.
 *
 * added scissor clipping.
 *
 * Revision 1.38  2002/06/01 03:35:27  relnev
 * fix typo
 *
 * Revision 1.37  2002/06/01 03:32:00  relnev
 * fix texture loading mistake.
 *
 * enable some d3d stuff for opengl also
 *
 * Revision 1.36  2002/05/31 23:25:03  relnev
 * line fixes
 *
 * Revision 1.34  2002/05/31 22:15:22  relnev
 * BGRA
 *
 * Revision 1.33  2002/05/31 22:04:55  relnev
 * use d3d rect_internal
 *
 * Revision 1.32  2002/05/31 06:28:23  relnev
 * more stuff
 *
 * Revision 1.31  2002/05/31 06:04:39  relnev
 * fog
 *
 * Revision 1.30  2002/05/31 03:56:11  theoddone33
 * Change tmapper polygon winding and enable culling
 *
 * Revision 1.29  2002/05/31 03:34:02  theoddone33
 * Fix Keyboard
 * Add titlebar
 *
 * Revision 1.28  2002/05/31 00:06:59  relnev
 * minor change
 *
 * Revision 1.27  2002/05/30 23:46:29  theoddone33
 * some minor key changes (not necessarily fixes)
 *
 * Revision 1.26  2002/05/30 23:33:12  relnev
 * implemented a few more functions.
 *
 * Revision 1.25  2002/05/30 23:01:16  relnev
 * implement gr_opengl_set_state.
 *
 * Revision 1.24  2002/05/30 22:12:57  relnev
 * finish default texture case
 *
 * Revision 1.23  2002/05/30 22:02:30  theoddone33
 * More gl changes
 *
 * Revision 1.22  2002/05/30 21:44:48  relnev
 * implemented some missing texture stuff.
 *
 * enable bitmap polys for opengl.
 *
 * work around greenness in bitmaps.
 *
 * Revision 1.21  2002/05/30 17:29:30  theoddone33
 * Fix some more stubs, change at least one polygon winding since culling is now
 * enabled.
 *
 * Revision 1.20  2002/05/30 16:50:24  theoddone33
 * Keyboard partially fixed
 *
 * Revision 1.19  2002/05/30 08:13:14  relnev
 * fonts are fixed
 *
 * Revision 1.18  2002/05/29 23:37:36  relnev
 * fix bitmap bug
 *
 * Revision 1.17  2002/05/29 23:17:49  theoddone33
 * Non working text code and fixed keys
 *
 * Revision 1.16  2002/05/29 19:45:13  theoddone33
 * More changes on texture loading
 *
 * Revision 1.15  2002/05/29 19:06:48  theoddone33
 * Enable string printing.  Enable texture mapping
 *
 * Revision 1.14  2002/05/29 08:54:40  relnev
 * "fixed" bitmap drawing.
 *
 * copied more d3d code over.
 *
 * Revision 1.13  2002/05/29 06:25:13  theoddone33
 * Keyboard input, mouse tracking now work
 *
 * Revision 1.12  2002/05/29 04:52:45  relnev
 * bitmap
 *
 * Revision 1.11  2002/05/29 04:29:56  relnev
 * removed some unncessary stubbing, implemented opengl rect
 *
 * Revision 1.10  2002/05/29 04:13:27  theoddone33
 * enable opengl_line
 *
 * Revision 1.9  2002/05/29 03:35:51  relnev
 * added rest of init
 *
 * Revision 1.8  2002/05/29 03:30:05  relnev
 * update opengl stubs
 *
 * Revision 1.7  2002/05/29 02:52:32  theoddone33
 * Enable OpenGL renderer
 *
 * Revision 1.6  2002/05/28 04:56:51  theoddone33
 * runs a little bit now
 *
 * Revision 1.5  2002/05/28 04:07:28  theoddone33
 * New graphics stubbing arrangement
 *
 * Revision 1.4  2002/05/27 23:39:34  relnev
 * 0
 *
 * Revision 1.3  2002/05/27 22:35:01  theoddone33
 * more symbols
 *
 * Revision 1.2  2002/05/27 22:32:02  theoddone33
 * throw all d3d stuff at opengl
 *
 * Revision 1.1.1.1  2002/05/03 03:28:09  root
 * Initial import.
 *
 * 
 * 10    7/14/99 9:42a Dave
 * Put in clear_color debug function. Put in base for 3dnow stuff / P3
 * stuff
 * 
 * 9     7/09/99 9:51a Dave
 * Added thick polyline code.
 * 
 * 8     6/29/99 10:35a Dave
 * Interface polygon bitmaps! Whee!
 * 
 * 7     2/03/99 11:44a Dave
 * Fixed d3d transparent textures.
 * 
 * 6     1/24/99 11:37p Dave
 * First full rev of beam weapons. Very customizable. Removed some bogus
 * Int3()'s in low level net code.
 * 
 * 5     12/18/98 1:13a Dave
 * Rough 1024x768 support for Direct3D. Proper detection and usage through
 * the launcher.
 * 
 * 4     12/06/98 2:36p Dave
 * Drastically improved nebula fogging.
 * 
 * 3     11/11/98 5:37p Dave
 * Checkin for multiplayer testing.
 * 
 * 2     10/07/98 10:53a Dave
 * Initial checkin.
 * 
 * 1     10/07/98 10:49a Dave
 * 
 * 14    5/20/98 9:46p John
 * added code so the places in code that change half the palette don't
 * have to clear the screen.
 * 
 * 13    5/06/98 5:30p John
 * Removed unused cfilearchiver.  Removed/replaced some unused/little used
 * graphics functions, namely gradient_h and _v and pixel_sp.   Put in new
 * DirectX header files and libs that fixed the Direct3D alpha blending
 * problems.
 * 
 * 12    4/14/98 12:15p John
 * Made 16-bpp movies work.
 * 
 * 11    3/12/98 5:36p John
 * Took out any unused shaders.  Made shader code take rgbc instead of
 * matrix and vector since noone used it like a matrix and it would have
 * been impossible to do in hardware.   Made Glide implement a basic
 * shader for online help.  
 * 
 * 10    3/10/98 4:18p John
 * Cleaned up graphics lib.  Took out most unused gr functions.   Made D3D
 * & Glide have popups and print screen.  Took out all >8bpp software
 * support.  Made Fred zbuffer.  Made zbuffer allocate dynamically to
 * support Fred.  Made zbuffering key off of functions rather than one
 * global variable.
 * 
 * 9     12/02/97 4:00p John
 * Added first rev of thruster glow, along with variable levels of
 * translucency, which retquired some restructing of palman.
 * 
 * 8     10/03/97 9:10a John
 * added better antialiased line drawer
 * 
 * 7     9/23/97 10:45a John
 * made so you can tell bitblt code to rle a bitmap by passing flag to
 * gr_set_bitmap
 * 
 * 6     9/09/97 11:01a Sandeep
 * fixed warning level 4 bugs
 * 
 * 5     7/10/97 2:06p John
 * added code to specify alphablending type for bitmaps.
 * 
 * 4     6/17/97 7:04p John
 * added d3d support for gradients.
 * fixed some color bugs by adding screen signatures instead of watching
 * flags and palette changes.
 * 
 * 3     6/12/97 2:50a Lawrance
 * bm_unlock() now passed bitmap number, not pointer
 * 
 * 2     6/11/97 1:12p John
 * Started fixing all the text colors in the game.
 * 
 * 1     5/12/97 12:14p John
 *
 * $NoKeywords: $
 */

#ifndef PLAT_UNIX
#include <windows.h>
#include <windowsx.h>
#endif

#ifdef __APPLE__
#include <OpenGL/gl.h>
#else
#include <GL/gl.h>
#endif

#include "pstypes.h"
#include "osapi.h"
#include "2d.h"
#include "3d.h"
#include "bmpman.h"
#include "floating.h"
#include "palman.h"
#include "systemvars.h"
#include "grinternal.h"
#include "gropengl.h"
#include "line.h"
#include "neb.h"
#include "mouse.h"
#include "osregistry.h"
#include "cmdline.h"
#include "cfile.h"

static int Inited = 0;

typedef enum gr_texture_source {
        TEXTURE_SOURCE_NONE,
        TEXTURE_SOURCE_DECAL,
        TEXTURE_SOURCE_NO_FILTERING,
} gr_texture_source;

typedef enum gr_alpha_blend {
        ALPHA_BLEND_NONE,                       // 1*SrcPixel + 0*DestPixel
        ALPHA_BLEND_ADDITIVE,                   // 1*SrcPixel + 1*DestPixel
        ALPHA_BLEND_ALPHA_ADDITIVE,             // Alpha*SrcPixel + 1*DestPixel
        ALPHA_BLEND_ALPHA_BLEND_ALPHA,          // Alpha*SrcPixel + (1-Alpha)*DestPixel
        ALPHA_BLEND_ALPHA_BLEND_SRC_COLOR,      // Alpha*SrcPixel + (1-SrcPixel)*DestPixel
} gr_alpha_blend;

typedef enum gr_zbuffer_type {
        ZBUFFER_TYPE_NONE,
        ZBUFFER_TYPE_READ,
        ZBUFFER_TYPE_WRITE,
        ZBUFFER_TYPE_FULL,
} gr_zbuffer_type;
                        
#define NEBULA_COLORS 20

volatile int GL_activate = 0;
volatile int GL_deactivate = 0;

static int GL_use_luminance_alpha;
static int FSAA;

static char *Gr_saved_screen = NULL;
static int Gr_saved_screen_bitmap;

#ifdef PLAT_UNIX
// Throw in some dummy functions - DDOI

int D3D_32bit = 0;              // grd3d.cpp
int D3D_fog_mode = -1;          // grd3d.cpp
int D3D_inited = 0;             // grd3d.cpp
int D3D_zbias = 1;              // grd3d.cpp
int D3d_rendition_uvs = 0;      // grd3d.cpp

void d3d_flush ()
{
        STUB_FUNCTION;
}

void d3d_zbias (int a)
{
        STUB_FUNCTION;
}
#endif

static void gr_opengl_set_texture_state(gr_texture_source ts);

static gr_alpha_blend GL_current_alpha_blend = (gr_alpha_blend) -1;
static gr_zbuffer_type GL_current_zbuffer_type = (gr_zbuffer_type) -1;

static void gr_opengl_set_state(gr_texture_source ts, gr_alpha_blend ab, gr_zbuffer_type zt)
{
        gr_opengl_set_texture_state(ts);
        
        if (ab != GL_current_alpha_blend) {
                switch (ab) {
                        case ALPHA_BLEND_NONE:                  // 1*SrcPixel + 0*DestPixel
                                glBlendFunc(GL_ONE, GL_ZERO);
                                break;
                        case ALPHA_BLEND_ADDITIVE:              // 1*SrcPixel + 1*DestPixel
                                glBlendFunc(GL_ONE, GL_ONE);
                                break;
                        case ALPHA_BLEND_ALPHA_ADDITIVE:        // Alpha*SrcPixel + 1*DestPixel
                                glBlendFunc(GL_SRC_ALPHA, GL_ONE);
                                break;
                        case ALPHA_BLEND_ALPHA_BLEND_ALPHA:     // Alpha*SrcPixel + (1-Alpha)*DestPixel
                                glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
                                break;
                        case ALPHA_BLEND_ALPHA_BLEND_SRC_COLOR: // Alpha*SrcPixel + (1-SrcPixel)*DestPixel
                                glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_COLOR);
                                break;
                        default:
                                break;
                }
                
                GL_current_alpha_blend = ab;
        }
        
        if (zt != GL_current_zbuffer_type) {
                switch (zt) {
                        case ZBUFFER_TYPE_NONE:
                                glDepthFunc(GL_ALWAYS);
                                glDepthMask(GL_FALSE);
                                break;
                        case ZBUFFER_TYPE_READ:
                                glDepthFunc(GL_LESS);
                                glDepthMask(GL_FALSE);  
                                break;
                        case ZBUFFER_TYPE_WRITE:
                                glDepthFunc(GL_ALWAYS);
                                glDepthMask(GL_TRUE);
                                break;
                        case ZBUFFER_TYPE_FULL:
                                glDepthFunc(GL_LESS);
                                glDepthMask(GL_TRUE);
                                break;
                        default:
                                break;
                }
                
                GL_current_zbuffer_type = zt;
        }       
}

void gr_opengl_activate(int active)
{
        if (active) {
                GL_activate++;
                
                // don't grab key/mouse if cmdline says so or if we're fullscreen
                if(!Cmdline_no_grab && !(SDL_GetVideoSurface()->flags & SDL_FULLSCREEN)) {
                        SDL_WM_GrabInput(SDL_GRAB_ON);
                }
        } else {
                GL_deactivate++;
                
                // let go of mouse/keyboard
                SDL_WM_GrabInput(SDL_GRAB_OFF);
        }
}


static void opengl_tcache_flush ();

void gr_opengl_preload_init()
{
        if (gr_screen.mode != GR_OPENGL) {
                return;
        }

        opengl_tcache_flush ();
}

int GL_should_preload = 0;
int gr_opengl_preload(int bitmap_num, int is_aabitmap)
{
        if ( gr_screen.mode != GR_OPENGL) {
                return 0;
        }

        if ( !GL_should_preload )      {
                return 0;
        }

        float u_scale, v_scale;

        int retval;
        if ( is_aabitmap )      {
                retval = gr_tcache_set(bitmap_num, TCACHE_TYPE_AABITMAP, &u_scale, &v_scale, 1, -1, -1, 0 );
        } else {
                retval = gr_tcache_set(bitmap_num, TCACHE_TYPE_NORMAL, &u_scale, &v_scale, 1, -1, -1, 0 );
        }

        if ( !retval )  {
                mprintf(("Texture upload failed!\n" ));
        }

        return retval;
}

void gr_opengl_pixel(int x, int y)
{
        gr_line(x,y,x,y);
}

void gr_opengl_clear()
{
        glClearColor(gr_screen.current_clear_color.red / 255.0, 
                gr_screen.current_clear_color.green / 255.0, 
                gr_screen.current_clear_color.blue / 255.0, 1.0);

        glClear ( GL_COLOR_BUFFER_BIT );
}

void gr_opengl_save_mouse_area(int x, int y, int w, int h);
static void opengl_tcache_frame ();

void gr_opengl_flip()
{
        if (!Inited) return;

        gr_reset_clip();

        mouse_eval_deltas();
        
        extern int Gr_opengl_mouse_saved;
        Gr_opengl_mouse_saved = 0;
        
        if ( mouse_is_visible() )       {
                int mx, my;
                
                gr_reset_clip();
                mouse_get_pos( &mx, &my );
                
                gr_opengl_save_mouse_area(mx,my,32,32);
                
                if ( Gr_cursor == -1 )  {
                        // stuff
                } else {
                        gr_set_bitmap(Gr_cursor, GR_ALPHABLEND_NONE, GR_BITBLT_MODE_NORMAL, 1.0f, -1, -1);
                        gr_bitmap( mx, my );
                }
         }
         
#ifndef NDEBUG
        GLenum error = glGetError();
        int ic = 0;
        do {
                error = glGetError();
                
                if (error != GL_NO_ERROR) {
                        nprintf(("Warning", "!!DEBUG!! OpenGL Error: %d (%d this frame)\n", error, ic));
                }
                ic++;
        } while (error != GL_NO_ERROR);
#endif
        
        SDL_GL_SwapBuffers ();

        opengl_tcache_frame ();
        
        int cnt = GL_activate;
        if ( cnt )      {
                GL_activate-=cnt;
                opengl_tcache_flush();
                // gr_opengl_clip_cursor(1); /* mouse grab, see opengl_activate */
        }
        
        cnt = GL_deactivate;
        if ( cnt )      {
                GL_deactivate-=cnt;
                // gr_opengl_clip_cursor(0);  /* mouse grab, see opengl_activate */
        }
}

void gr_opengl_flip_window(uint _hdc, int x, int y, int w, int h )
{
        // Not used.
}

void gr_opengl_set_clip(int x,int y,int w,int h)
{
        // check for sanity of parameters
        if (x < 0)
                x = 0;
        if (y < 0)
                y = 0;

        if (x >= gr_screen.max_w)
                x = gr_screen.max_w - 1;
        if (y >= gr_screen.max_h)
                y = gr_screen.max_h - 1;

        if (x + w > gr_screen.max_w)
                w = gr_screen.max_w - x;
        if (y + h > gr_screen.max_h)
                h = gr_screen.max_h - y;
        
        if (w > gr_screen.max_w)
                w = gr_screen.max_w;
        if (h > gr_screen.max_h)
                h = gr_screen.max_h;
        
        gr_screen.offset_x = x;
        gr_screen.offset_y = y;
        gr_screen.clip_left = 0;
        gr_screen.clip_right = w-1;
        gr_screen.clip_top = 0;
        gr_screen.clip_bottom = h-1;
        gr_screen.clip_width = w;
        gr_screen.clip_height = h;
        
        glEnable(GL_SCISSOR_TEST);
        glScissor(x, gr_screen.max_h-y-h, w, h);
}

void gr_opengl_reset_clip()
{
        gr_screen.offset_x = 0;
        gr_screen.offset_y = 0;
        gr_screen.clip_left = 0;
        gr_screen.clip_top = 0;
        gr_screen.clip_right = gr_screen.max_w - 1;
        gr_screen.clip_bottom = gr_screen.max_h - 1;
        gr_screen.clip_width = gr_screen.max_w;
        gr_screen.clip_height = gr_screen.max_h;
        
        glDisable(GL_SCISSOR_TEST);
//      glScissor(0, 0, gr_screen.max_w, gr_screen.max_h);
}

void gr_opengl_set_bitmap( int bitmap_num, int alphablend_mode = GR_ALPHABLEND_NONE, int bitblt_mode = GR_BITBLT_MODE_NORMAL, float alpha = 1.0f, int sx = -1, int sy = -1 )
{
        gr_screen.current_alpha = alpha;
        gr_screen.current_alphablend_mode = alphablend_mode;
        gr_screen.current_bitblt_mode = bitblt_mode;
        gr_screen.current_bitmap = bitmap_num;

        gr_screen.current_bitmap_sx = sx;
        gr_screen.current_bitmap_sy = sy;
}

void gr_opengl_create_shader(shader * shade, float r, float g, float b, float c )
{
        shade->screen_sig = gr_screen.signature;
        shade->r = r;
        shade->g = g;
        shade->b = b;
        shade->c = c;   
}

void gr_opengl_set_shader( shader * shade )
{       
        if ( shade )    {
                if (shade->screen_sig != gr_screen.signature)   {
                        gr_create_shader( shade, shade->r, shade->g, shade->b, shade->c );
                }
                gr_screen.current_shader = *shade;
        } else {
                gr_create_shader( &gr_screen.current_shader, 0.0f, 0.0f, 0.0f, 0.0f );
        }
}


void gr_opengl_bitmap_ex(int x,int y,int w,int h,int sx,int sy)
{
        STUB_FUNCTION; /* who called me? */
}

void gr_opengl_bitmap(int x, int y)
{
        STUB_FUNCTION; /* who called me? */
}

static void gr_opengl_rect_internal(int x, int y, int w, int h, int r, int g, int b, int a)
{
        int saved_zbuf;
        vertex v[4];
        vertex *verts[4] = {&v[0], &v[1], &v[2], &v[3]};

        saved_zbuf = gr_zbuffer_get();
        
        // start the frame, no zbuffering, no culling
        g3_start_frame(1);      
        gr_zbuffer_set(GR_ZBUFF_NONE);          
        gr_set_cull(0);         

        // stuff coords         
        v[0].sx = i2fl(x);
        v[0].sy = i2fl(y);
        v[0].sw = 0.0f;
        v[0].u = 0.0f;
        v[0].v = 0.0f;
        v[0].flags = PF_PROJECTED;
        v[0].codes = 0;
        v[0].r = (ubyte)r;
        v[0].g = (ubyte)g;
        v[0].b = (ubyte)b;
        v[0].a = (ubyte)a;

        v[1].sx = i2fl(x + w);
        v[1].sy = i2fl(y);      
        v[1].sw = 0.0f;
        v[1].u = 0.0f;
        v[1].v = 0.0f;
        v[1].flags = PF_PROJECTED;
        v[1].codes = 0;
        v[1].r = (ubyte)r;
        v[1].g = (ubyte)g;
        v[1].b = (ubyte)b;
        v[1].a = (ubyte)a;

        v[2].sx = i2fl(x + w);
        v[2].sy = i2fl(y + h);
        v[2].sw = 0.0f;
        v[2].u = 0.0f;
        v[2].v = 0.0f;
        v[2].flags = PF_PROJECTED;
        v[2].codes = 0;
        v[2].r = (ubyte)r;
        v[2].g = (ubyte)g;
        v[2].b = (ubyte)b;
        v[2].a = (ubyte)a;

        v[3].sx = i2fl(x);
        v[3].sy = i2fl(y + h);
        v[3].sw = 0.0f;
        v[3].u = 0.0f;
        v[3].v = 0.0f;
        v[3].flags = PF_PROJECTED;
        v[3].codes = 0;                         
        v[3].r = (ubyte)r;
        v[3].g = (ubyte)g;
        v[3].b = (ubyte)b;
        v[3].a = (ubyte)a;

        // draw the polys
        g3_draw_poly_constant_sw(4, verts, TMAP_FLAG_GOURAUD | TMAP_FLAG_RGB | TMAP_FLAG_ALPHA, 0.1f);          

        g3_end_frame();

        // restore zbuffer and culling
        gr_zbuffer_set(saved_zbuf);
        gr_set_cull(1); 
}

void gr_opengl_rect(int x,int y,int w,int h)
{
        gr_opengl_rect_internal(x, y, w, h, gr_screen.current_color.red, gr_screen.current_color.green, gr_screen.current_color.blue, gr_screen.current_color.alpha);
}

void gr_opengl_shade(int x,int y,int w,int h)
{
        int r,g,b,a;
        
        float shade1 = 1.0f;
        float shade2 = 6.0f;

        r = fl2i(gr_screen.current_shader.r*255.0f*shade1);
        if ( r < 0 ) r = 0; else if ( r > 255 ) r = 255;
        g = fl2i(gr_screen.current_shader.g*255.0f*shade1);
        if ( g < 0 ) g = 0; else if ( g > 255 ) g = 255;
        b = fl2i(gr_screen.current_shader.b*255.0f*shade1);
        if ( b < 0 ) b = 0; else if ( b > 255 ) b = 255;
        a = fl2i(gr_screen.current_shader.c*255.0f*shade2);
        if ( a < 0 ) a = 0; else if ( a > 255 ) a = 255;

        gr_opengl_rect_internal(x, y, w, h, r, g, b, a);        
}

static void gr_opengl_aabitmap_ex_internal(int x,int y,int w,int h,int sx,int sy)
{
        if ( w < 1 ) return;
        if ( h < 1 ) return;

        if ( !gr_screen.current_color.is_alphacolor )   return;

        float u_scale, v_scale;

        if ( !gr_tcache_set( gr_screen.current_bitmap, TCACHE_TYPE_AABITMAP, &u_scale, &v_scale, 0, -1, -1, 0 ) )       {
                // Couldn't set texture
                mprintf(( "WARNING: Error setting aabitmap texture!\n" ));
                return;
        }

        gr_opengl_set_state( TEXTURE_SOURCE_NO_FILTERING, ALPHA_BLEND_ALPHA_BLEND_ALPHA, ZBUFFER_TYPE_NONE );
        
        float u0, u1, v0, v1;
        float x1, x2, y1, y2;
        int bw, bh;

        bm_get_info( gr_screen.current_bitmap, &bw, &bh );

        u0 = u_scale*i2fl(sx)/i2fl(bw);
        v0 = v_scale*i2fl(sy)/i2fl(bh);

        u1 = u_scale*i2fl(sx+w)/i2fl(bw);
        v1 = v_scale*i2fl(sy+h)/i2fl(bh);

        x1 = i2fl(x+gr_screen.offset_x);
        y1 = i2fl(y+gr_screen.offset_y);
        x2 = i2fl(x+w+gr_screen.offset_x);
        y2 = i2fl(y+h+gr_screen.offset_y);

        if ( gr_screen.current_color.is_alphacolor )    {
                glColor4ub(gr_screen.current_color.red, gr_screen.current_color.green, gr_screen.current_color.blue,gr_screen.current_color.alpha);
        } else {
                glColor3ub(gr_screen.current_color.red, gr_screen.current_color.green, gr_screen.current_color.blue);
        }

        glBegin (GL_QUADS);
          glTexCoord2f (u0, v1);
          glVertex3f (x1, y2, -0.99);

          glTexCoord2f (u1, v1);
          glVertex3f (x2, y2, -0.99);

          glTexCoord2f (u1, v0);
          glVertex3f (x2, y1, -0.99);

          glTexCoord2f (u0, v0);
          glVertex3f (x1, y1, -0.99);
        glEnd ();
}

void gr_opengl_aabitmap_ex(int x,int y,int w,int h,int sx,int sy)
{
        int reclip;
        #ifndef NDEBUG
        int count = 0;
        #endif

        int dx1=x, dx2=x+w-1;
        int dy1=y, dy2=y+h-1;

        int bw, bh;
        bm_get_info( gr_screen.current_bitmap, &bw, &bh, NULL );

        do {
                reclip = 0;
                #ifndef NDEBUG
                        if ( count > 1 ) Int3();
                        count++;
                #endif
        
                if ((dx1 > gr_screen.clip_right ) || (dx2 < gr_screen.clip_left)) return;
                if ((dy1 > gr_screen.clip_bottom ) || (dy2 < gr_screen.clip_top)) return;
                if ( dx1 < gr_screen.clip_left ) { sx += gr_screen.clip_left-dx1; dx1 = gr_screen.clip_left; }
                if ( dy1 < gr_screen.clip_top ) { sy += gr_screen.clip_top-dy1; dy1 = gr_screen.clip_top; }
                if ( dx2 > gr_screen.clip_right )       { dx2 = gr_screen.clip_right; }
                if ( dy2 > gr_screen.clip_bottom )      { dy2 = gr_screen.clip_bottom; }

                if ( sx < 0 ) {
                        dx1 -= sx;
                        sx = 0;
                        reclip = 1;
                }

                if ( sy < 0 ) {
                        dy1 -= sy;
                        sy = 0;
                        reclip = 1;
                }

                w = dx2-dx1+1;
                h = dy2-dy1+1;

                if ( sx + w > bw ) {
                        w = bw - sx;
                        dx2 = dx1 + w - 1;
                }

                if ( sy + h > bh ) {
                        h = bh - sy;
                        dy2 = dy1 + h - 1;
                }

                if ( w < 1 ) return;            // clipped away!
                if ( h < 1 ) return;            // clipped away!

        } while (reclip);

        // Make sure clipping algorithm works
        #ifndef NDEBUG
                Assert( w > 0 );
                Assert( h > 0 );
                Assert( w == (dx2-dx1+1) );
                Assert( h == (dy2-dy1+1) );
                Assert( sx >= 0 );
                Assert( sy >= 0 );
                Assert( sx+w <= bw );
                Assert( sy+h <= bh );
                Assert( dx2 >= dx1 );
                Assert( dy2 >= dy1 );
                Assert( (dx1 >= gr_screen.clip_left ) && (dx1 <= gr_screen.clip_right) );
                Assert( (dx2 >= gr_screen.clip_left ) && (dx2 <= gr_screen.clip_right) );
                Assert( (dy1 >= gr_screen.clip_top ) && (dy1 <= gr_screen.clip_bottom) );
                Assert( (dy2 >= gr_screen.clip_top ) && (dy2 <= gr_screen.clip_bottom) );
        #endif

        // We now have dx1,dy1 and dx2,dy2 and sx, sy all set validly within clip regions.
        gr_opengl_aabitmap_ex_internal(dx1,dy1,dx2-dx1+1,dy2-dy1+1,sx,sy);
}

void gr_opengl_aabitmap(int x, int y)
{
        int w, h;

        bm_get_info( gr_screen.current_bitmap, &w, &h, NULL );
        int dx1=x, dx2=x+w-1;
        int dy1=y, dy2=y+h-1;
        int sx=0, sy=0;

        if ((dx1 > gr_screen.clip_right ) || (dx2 < gr_screen.clip_left)) return;
        if ((dy1 > gr_screen.clip_bottom ) || (dy2 < gr_screen.clip_top)) return;
        if ( dx1 < gr_screen.clip_left ) { sx = gr_screen.clip_left-dx1; dx1 = gr_screen.clip_left; }
        if ( dy1 < gr_screen.clip_top ) { sy = gr_screen.clip_top-dy1; dy1 = gr_screen.clip_top; }
        if ( dx2 > gr_screen.clip_right )       { dx2 = gr_screen.clip_right; }
        if ( dy2 > gr_screen.clip_bottom )      { dy2 = gr_screen.clip_bottom; }

        if ( sx < 0 ) return;
        if ( sy < 0 ) return;
        if ( sx >= w ) return;
        if ( sy >= h ) return;

        // Draw bitmap bm[sx,sy] into (dx1,dy1)-(dx2,dy2)
        gr_aabitmap_ex(dx1,dy1,dx2-dx1+1,dy2-dy1+1,sx,sy);
}

void gr_opengl_string( int sx, int sy, char *s )
{
        int width, spacing, letter;
        int x, y;

        if ( !Current_font )    {
                return;
        }

        gr_set_bitmap(Current_font->bitmap_id, GR_ALPHABLEND_NONE, GR_BITBLT_MODE_NORMAL, 1.0f, -1, -1);

        x = sx;
        y = sy;

        if (sx==0x8000) {                       //centered
                x = get_centered_x(s);
        } else {
                x = sx;
        }
        
        spacing = 0;

        while (*s)      {
                x += spacing;

                while (*s== '\n' )      {
                        s++;
                        y += Current_font->h;
                        if (sx==0x8000) {                       //centered
                                x = get_centered_x(s);
                        } else {
                                x = sx;
                        }
                }
                if (*s == 0 ) break;

                letter = get_char_width(s[0],s[1],&width,&spacing);
                s++;

                //not in font, draw as space
                if (letter<0)   {
                        continue;
                }

                int xd, yd, xc, yc;
                int wc, hc;

                // Check if this character is totally clipped
                if ( x + width < gr_screen.clip_left ) continue;
                if ( y + Current_font->h < gr_screen.clip_top ) continue;
                if ( x > gr_screen.clip_right ) continue;
                if ( y > gr_screen.clip_bottom ) continue;

                xd = yd = 0;
                if ( x < gr_screen.clip_left ) xd = gr_screen.clip_left - x;
                if ( y < gr_screen.clip_top ) yd = gr_screen.clip_top - y;
                xc = x+xd;
                yc = y+yd;

                wc = width - xd; hc = Current_font->h - yd;
                if ( xc + wc > gr_screen.clip_right ) wc = gr_screen.clip_right - xc;
                if ( yc + hc > gr_screen.clip_bottom ) hc = gr_screen.clip_bottom - yc;

                if ( wc < 1 ) continue;
                if ( hc < 1 ) continue;

                int u = Current_font->bm_u[letter];
                int v = Current_font->bm_v[letter];

                gr_opengl_aabitmap_ex_internal( xc, yc, wc, hc, u+xd, v+yd );
        }
}

void gr_opengl_line(int x1,int y1,int x2,int y2)
{
        int clipped = 0, swapped=0;

        gr_opengl_set_state( TEXTURE_SOURCE_NONE, ALPHA_BLEND_ALPHA_BLEND_ALPHA, ZBUFFER_TYPE_NONE );
        
        INT_CLIPLINE(x1,y1,x2,y2,gr_screen.clip_left,gr_screen.clip_top,gr_screen.clip_right,gr_screen.clip_bottom,return,clipped=1,swapped=1);
        
        float sx1, sy1;
        float sx2, sy2;
        
        sx1 = i2fl(x1 + gr_screen.offset_x)+0.5;
        sy1 = i2fl(y1 + gr_screen.offset_y)+0.5;
        sx2 = i2fl(x2 + gr_screen.offset_x)+0.5;
        sy2 = i2fl(y2 + gr_screen.offset_y)+0.5;
        
        if ( x1 == x2 && y1 == y2 ) {
                glBegin (GL_POINTS);
                  glColor4ub (gr_screen.current_color.red, gr_screen.current_color.green, gr_screen.current_color.blue, gr_screen.current_color.alpha);
                  glVertex3f (sx1, sy1, -0.99f);
                glEnd ();
                
                return;
        }
        
        if ( x1 == x2 ) {
                if ( sy1 < sy2 )    {
                        sy2 += 0.5f;
                } else {
                        sy1 += 0.5f;
                }
        } else if ( y1 == y2 )  {
                if ( sx1 < sx2 )    {
                        sx2 += 0.5f;
                } else {
                        sx1 += 0.5f;
                }
        }
        
        glBegin (GL_LINES);
          glColor4ub (gr_screen.current_color.red, gr_screen.current_color.green, gr_screen.current_color.blue, gr_screen.current_color.alpha);
          glVertex3f (sx2, sy2, -0.99f);
          glVertex3f (sx1, sy1, -0.99f);
        glEnd ();
}

void gr_opengl_aaline(vertex *v1, vertex *v2)
{
        gr_opengl_line( fl2i(v1->sx), fl2i(v1->sy), fl2i(v2->sx), fl2i(v2->sy) );
}

void gr_opengl_gradient(int x1,int y1,int x2,int y2)
{
        int clipped = 0, swapped=0;

        if ( !gr_screen.current_color.is_alphacolor )   {
                gr_line( x1, y1, x2, y2 );
                return;
        }

        INT_CLIPLINE(x1,y1,x2,y2,gr_screen.clip_left,gr_screen.clip_top,gr_screen.clip_right,gr_screen.clip_bottom,return,clipped=1,swapped=1);

        gr_opengl_set_state( TEXTURE_SOURCE_NONE, ALPHA_BLEND_ALPHA_BLEND_ALPHA, ZBUFFER_TYPE_NONE );

        int aa = swapped ? 0 : gr_screen.current_color.alpha;
        int ba = swapped ? gr_screen.current_color.alpha : 0;
        
        float sx1, sy1;
        float sx2, sy2;
        
        sx1 = i2fl(x1 + gr_screen.offset_x)+0.5;
        sy1 = i2fl(y1 + gr_screen.offset_y)+0.5;
        sx2 = i2fl(x2 + gr_screen.offset_x)+0.5;
        sy2 = i2fl(y2 + gr_screen.offset_y)+0.5;

        if ( x1 == x2 ) {
                if ( sy1 < sy2 )    {
                        sy2 += 0.5f;
                } else {
                        sy1 += 0.5f;
                }
        } else if ( y1 == y2 )  {
                if ( sx1 < sx2 )    {
                        sx2 += 0.5f;
                } else {
                        sx1 += 0.5f;
                }
        }
        
        glBegin (GL_LINES);
          glColor4ub (gr_screen.current_color.red, gr_screen.current_color.green, gr_screen.current_color.blue, ba);
          glVertex3f (sx2, sy2, -0.99f);
          glColor4ub (gr_screen.current_color.red, gr_screen.current_color.green, gr_screen.current_color.blue, aa);
          glVertex3f (sx1, sy1, -0.99f);
        glEnd ();       
}

void gr_opengl_circle( int xc, int yc, int d )
{
        int p,x, y, r;

        r = d/2;
        p=3-d;
        x=0;
        y=r;

        // Big clip
        if ( (xc+r) < gr_screen.clip_left ) return;
        if ( (xc-r) > gr_screen.clip_right ) return;
        if ( (yc+r) < gr_screen.clip_top ) return;
        if ( (yc-r) > gr_screen.clip_bottom ) return;

        while(x<y)      {
                // Draw the first octant
                gr_opengl_line( xc-y, yc-x, xc+y, yc-x );
                gr_opengl_line( xc-y, yc+x, xc+y, yc+x );
                                
                if (p<0) 
                        p=p+(x<<2)+6;
                else    {
                        // Draw the second octant
                        gr_opengl_line( xc-x, yc-y, xc+x, yc-y );
                        gr_opengl_line( xc-x, yc+y, xc+x, yc+y );
                                                
                        p=p+((x-y)<<2)+10;
                        y--;
                }
                x++;
        }
        if(x==y) {
                gr_opengl_line( xc-x, yc-y, xc+x, yc-y );
                gr_opengl_line( xc-x, yc+y, xc+x, yc+y );
        }
        return;
}

static void gr_opengl_stuff_fog_value(float z, int *r, int *g, int *b, int *a)
{
        float f_float;
        
        f_float = (gr_screen.fog_far - z) / (gr_screen.fog_far - gr_screen.fog_near);
        if (f_float < 0.0f) {
                f_float = 0.0f;
        } else {
                f_float = 1.0f;
        }
        *r = 0;
        *g = 0;
        *b = 0;
        *a = (int)(f_float * 255.0);
}

static void gr_opengl_tmapper_internal( int nv, vertex ** verts, uint flags, int is_scaler )
{
        int i;
        float u_scale = 1.0f, v_scale = 1.0f;

        // Make nebula use the texture mapper... this blends the colors better.
        if ( flags & TMAP_FLAG_NEBULA ){
                Int3 ();
        }

        gr_texture_source texture_source = (gr_texture_source)-1;
        gr_alpha_blend alpha_blend = (gr_alpha_blend)-1;
        gr_zbuffer_type zbuffer_type = (gr_zbuffer_type)-1;
        
        if ( gr_zbuffering )    {
                if ( is_scaler || (gr_screen.current_alphablend_mode == GR_ALPHABLEND_FILTER)   )       {
                        zbuffer_type = ZBUFFER_TYPE_READ;
                } else {
                        zbuffer_type = ZBUFFER_TYPE_FULL;
                }
        } else {
                zbuffer_type = ZBUFFER_TYPE_NONE;
        }
        
        int alpha;

        int tmap_type = TCACHE_TYPE_NORMAL;

        int r, g, b;

        if ( flags & TMAP_FLAG_TEXTURED )       {
                r = g = b = 255;
        } else {
                r = gr_screen.current_color.red;
                g = gr_screen.current_color.green;
                b = gr_screen.current_color.blue;
        }

        if ( gr_screen.current_alphablend_mode == GR_ALPHABLEND_FILTER )        
        {
                if (1) {
                        tmap_type = TCACHE_TYPE_NORMAL;
                        alpha_blend = ALPHA_BLEND_ALPHA_ADDITIVE;
                        
                        // Blend with screen pixel using src*alpha+dst
                        float factor = gr_screen.current_alpha;
                        
                        alpha = 255;
                        
                        if ( factor <= 1.0f )   {
                                int tmp_alpha = fl2i(gr_screen.current_alpha*255.0f);
                                r = (r*tmp_alpha)/255;
                                g = (g*tmp_alpha)/255;
                                b = (b*tmp_alpha)/255;
                        }
                } else {
                        tmap_type = TCACHE_TYPE_XPARENT;
                        
                        alpha_blend = ALPHA_BLEND_ALPHA_BLEND_ALPHA;
                        
                        // Blend with screen pixel using src*alpha+dst
                        float factor = gr_screen.current_alpha;
                                
                        if ( factor > 1.0f )    {
                                alpha = 255;
                        } else {
                                alpha = fl2i(gr_screen.current_alpha*255.0f);
                        }
                }
        } else {
                if(Bm_pixel_format == BM_PIXEL_FORMAT_ARGB) {
                        alpha_blend = ALPHA_BLEND_ALPHA_BLEND_ALPHA;
                } else {
                        alpha_blend = ALPHA_BLEND_NONE;
                }
                alpha = 255;
        }

        if(flags & TMAP_FLAG_BITMAP_SECTION){
                tmap_type = TCACHE_TYPE_BITMAP_SECTION;
        }
        
        texture_source = TEXTURE_SOURCE_NONE;
        
        if ( flags & TMAP_FLAG_TEXTURED )       {
                if ( !gr_tcache_set(gr_screen.current_bitmap, tmap_type, &u_scale, &v_scale, 0, gr_screen.current_bitmap_sx, gr_screen.current_bitmap_sy, 0 ))
                {
                        mprintf(( "Not rendering a texture because it didn't fit in VRAM!\n" ));
                        return;
                }

                // use nonfiltered textures for bitmap sections
                if(flags & TMAP_FLAG_BITMAP_SECTION){
                        texture_source = TEXTURE_SOURCE_NO_FILTERING;
                } else {
                        texture_source = TEXTURE_SOURCE_DECAL;
                }
        }


        gr_opengl_set_state( texture_source, alpha_blend, zbuffer_type );
        
        if ( flags & TMAP_FLAG_TEXTURED )
        {
                // rendition junk
                // STUB_FUNCTION;
        }

        if (flags & TMAP_FLAG_PIXEL_FOG) {
                int r, g, b;
                int ra, ga, ba;
                ra = ga = ba = 0;
        
                /* argh */
                for (i=nv-1;i>=0;i--)   // DDOI - change polygon winding
                {
                        vertex * va = verts[i];
                        float sx, sy;
                
                        int x, y;
                        x = fl2i(va->sx*16.0f);
                        y = fl2i(va->sy*16.0f);
                
                        x += gr_screen.offset_x*16;
                        y += gr_screen.offset_y*16;
                
                        sx = i2fl(x) / 16.0f;
                        sy = i2fl(y) / 16.0f;
                
                        neb2_get_pixel((int)sx, (int)sy, &r, &g, &b);
                        
                        ra += r;
                        ga += g;
                        ba += b;
                }
                
                ra /= nv;
                ga /= nv;
                ba /= nv;
                
                gr_fog_set(GR_FOGMODE_FOG, ra, ga, ba, -1.0f, -1.0f);
        }
        
        glBegin(GL_TRIANGLE_FAN);
        for (i = nv-1; i >= 0; i--) {           
                vertex * va = verts[i];
                float sx, sy, sz;
                float tu, tv;
                float rhw;
                int a;
                
                if ( gr_zbuffering || (flags & TMAP_FLAG_NEBULA) )      {
                        sz = 1.0 - 1.0 / (1.0 + va->z / (32768.0 / 256.0));
                        
                        if ( sz > 0.98f ) {
                                sz = 0.98f;
                        }
                } else {
                        sz = 0.99f;
                }

                if ( flags & TMAP_FLAG_CORRECT )        {
                        rhw = va->sw;
                } else {
                        rhw = 1.0f;
                }
                
                if (flags & TMAP_FLAG_ALPHA) {
                        a = verts[i]->a;
                } else {
                        a = alpha;
                }

                if (flags & TMAP_FLAG_NEBULA ) {
                        int pal = (verts[i]->b*(NEBULA_COLORS-1))/255;
                        r = gr_palette[pal*3+0];
                        g = gr_palette[pal*3+1];
                        b = gr_palette[pal*3+2];
                } else if ( (flags & TMAP_FLAG_RAMP) && (flags & TMAP_FLAG_GOURAUD) )   {
                        r = Gr_gamma_lookup[verts[i]->b];
                        g = Gr_gamma_lookup[verts[i]->b];
                        b = Gr_gamma_lookup[verts[i]->b];
                } else if ( (flags & TMAP_FLAG_RGB)  && (flags & TMAP_FLAG_GOURAUD) )   {
                        // Make 0.75 be 256.0f
                        r = Gr_gamma_lookup[verts[i]->r];
                        g = Gr_gamma_lookup[verts[i]->g];
                        b = Gr_gamma_lookup[verts[i]->b];
                } else {
                        // use constant RGB values...
                }
                glColor4ub (r,g,b,a);

                if((gr_screen.current_fog_mode != GR_FOGMODE_NONE) && (D3D_fog_mode == 1)){
                        int sr, sg, sb, sa;
                        
                        /* this is for GL_EXT_SECONDARY_COLOR */
                        gr_opengl_stuff_fog_value(va->z, &sr, &sg, &sb, &sa);
                        /* do separate color call here */
                        
                        STUB_FUNCTION;
                }
                
                int x, y;
                x = fl2i(va->sx*16.0f);
                y = fl2i(va->sy*16.0f);

                x += gr_screen.offset_x*16;
                y += gr_screen.offset_y*16;
                
                sx = i2fl(x) / 16.0f;
                sy = i2fl(y) / 16.0f;

                if ( flags & TMAP_FLAG_TEXTURED )       {
                        tu = va->u*u_scale;
                        tv = va->v*v_scale;
                        glTexCoord2f(tu, tv);
                }
                
                glVertex4f(sx/rhw, sy/rhw, -sz/rhw, 1.0/rhw);
        }
        glEnd();
}

void gr_opengl_tmapper( int nverts, vertex **verts, uint flags )
{
        gr_opengl_tmapper_internal( nverts, verts, flags, 0 );
}

#define FIND_SCALED_NUM(x,x0,x1,y0,y1) (((((x)-(x0))*((y1)-(y0)))/((x1)-(x0)))+(y0))

void gr_opengl_scaler(vertex *va, vertex *vb )
{
        float x0, y0, x1, y1;
        float u0, v0, u1, v1;
        float clipped_x0, clipped_y0, clipped_x1, clipped_y1;
        float clipped_u0, clipped_v0, clipped_u1, clipped_v1;
        float xmin, xmax, ymin, ymax;
        int dx0, dy0, dx1, dy1;

        //============= CLIP IT =====================

        x0 = va->sx; y0 = va->sy;
        x1 = vb->sx; y1 = vb->sy;

        xmin = i2fl(gr_screen.clip_left); ymin = i2fl(gr_screen.clip_top);
        xmax = i2fl(gr_screen.clip_right); ymax = i2fl(gr_screen.clip_bottom);

        u0 = va->u; v0 = va->v;
        u1 = vb->u; v1 = vb->v;

        // Check for obviously offscreen bitmaps...
        if ( (y1<=y0) || (x1<=x0) ) return;
        if ( (x1<xmin ) || (x0>xmax) ) return;
        if ( (y1<ymin ) || (y0>ymax) ) return;

        clipped_u0 = u0; clipped_v0 = v0;
        clipped_u1 = u1; clipped_v1 = v1;

        clipped_x0 = x0; clipped_y0 = y0;
        clipped_x1 = x1; clipped_y1 = y1;

        // Clip the left, moving u0 right as necessary
        if ( x0 < xmin )        {
                clipped_u0 = FIND_SCALED_NUM(xmin,x0,x1,u0,u1);
                clipped_x0 = xmin;
        }

        // Clip the right, moving u1 left as necessary
        if ( x1 > xmax )        {
                clipped_u1 = FIND_SCALED_NUM(xmax,x0,x1,u0,u1);
                clipped_x1 = xmax;
        }

        // Clip the top, moving v0 down as necessary
        if ( y0 < ymin )        {
                clipped_v0 = FIND_SCALED_NUM(ymin,y0,y1,v0,v1);
                clipped_y0 = ymin;
        }

        // Clip the bottom, moving v1 up as necessary
        if ( y1 > ymax )        {
                clipped_v1 = FIND_SCALED_NUM(ymax,y0,y1,v0,v1);
                clipped_y1 = ymax;
        }
        
        dx0 = fl2i(clipped_x0); dx1 = fl2i(clipped_x1);
        dy0 = fl2i(clipped_y0); dy1 = fl2i(clipped_y1);

        if (dx1<=dx0) return;
        if (dy1<=dy0) return;

        //============= DRAW IT =====================

        vertex v[4];
        vertex *vl[4];

        vl[0] = &v[0];  
        v->sx = clipped_x0;
        v->sy = clipped_y0;
        v->sw = va->sw;
        v->z = va->z;
        v->u = clipped_u0;
        v->v = clipped_v0;

        vl[1] = &v[1];  
        v[1].sx = clipped_x1;
        v[1].sy = clipped_y0;
        v[1].sw = va->sw;
        v[1].z = va->z;
        v[1].u = clipped_u1;
        v[1].v = clipped_v0;

        vl[2] = &v[2];  
        v[2].sx = clipped_x1;
        v[2].sy = clipped_y1;
        v[2].sw = va->sw;
        v[2].z = va->z;
        v[2].u = clipped_u1;
        v[2].v = clipped_v1;

        vl[3] = &v[3];  
        v[3].sx = clipped_x0;
        v[3].sy = clipped_y1;
        v[3].sw = va->sw;
        v[3].z = va->z;
        v[3].u = clipped_u0;
        v[3].v = clipped_v1;

        gr_opengl_tmapper_internal( 4, vl, TMAP_FLAG_TEXTURED, 1 );
}

void gr_opengl_set_palette(ubyte *new_palette, int is_alphacolor)
{
}

void gr_opengl_get_color( int * r, int * g, int * b )
{
        if (r) *r = gr_screen.current_color.red;
        if (g) *g = gr_screen.current_color.green;
        if (b) *b = gr_screen.current_color.blue;
}

void gr_opengl_init_color(color *c, int r, int g, int b)
{
        c->screen_sig = gr_screen.signature;
        c->red = (unsigned char)r;
        c->green = (unsigned char)g;
        c->blue = (unsigned char)b;
        c->alpha = 255;
        c->ac_type = AC_TYPE_NONE;
        c->alphacolor = -1;
        c->is_alphacolor = 0;
        c->magic = 0xAC01;
}

void gr_opengl_init_alphacolor( color *clr, int r, int g, int b, int alpha, int type )
{
        if ( r < 0 ) r = 0; else if ( r > 255 ) r = 255;
        if ( g < 0 ) g = 0; else if ( g > 255 ) g = 255;
        if ( b < 0 ) b = 0; else if ( b > 255 ) b = 255;
        if ( alpha < 0 ) alpha = 0; else if ( alpha > 255 ) alpha = 255;

        gr_opengl_init_color( clr, r, g, b );

        clr->alpha = (unsigned char)alpha;
        clr->ac_type = (ubyte)type;
        clr->alphacolor = -1;
        clr->is_alphacolor = 1;
}

void gr_opengl_set_color( int r, int g, int b )
{
        Assert((r >= 0) && (r < 256));
        Assert((g >= 0) && (g < 256));
        Assert((b >= 0) && (b < 256));

        gr_opengl_init_color( &gr_screen.current_color, r, g, b );      
}

void gr_opengl_set_color_fast(color *dst)
{
        if ( dst->screen_sig != gr_screen.signature )   {
                if ( dst->is_alphacolor )       {
                        gr_opengl_init_alphacolor( dst, dst->red, dst->green, dst->blue, dst->alpha, dst->ac_type );
                } else {
                        gr_opengl_init_color( dst, dst->red, dst->green, dst->blue );
                }
        }
        gr_screen.current_color = *dst;
}

void gr_opengl_print_screen(char *filename)
{
#ifdef GL_VERSION_1_2
        char tmp[MAX_FILENAME_LEN];
        ubyte *buf = NULL;

        strcpy( tmp, filename );
        strcat( tmp, NOX(".tga"));

        CFILE *f = cfopen(tmp, "wb", CFILE_NORMAL, CF_TYPE_ROOT);

        if (f == NULL)
                return;

        // Write the TGA header
        cfwrite_ubyte( 0, f );  //      IDLength;
        cfwrite_ubyte( 0, f );  //      ColorMapType;
        cfwrite_ubyte( 2, f );  //      ImageType;              // 2 = 24bpp, uncompressed, 10=24bpp rle compressed
        cfwrite_ushort( 0, f ); // CMapStart;
        cfwrite_ushort( 0, f ); //      CMapLength;
        cfwrite_ubyte( 0, f );  // CMapDepth;
        cfwrite_ushort( 0, f ); //      XOffset;
        cfwrite_ushort( 0, f ); //      YOffset;
        cfwrite_ushort( (ushort)gr_screen.max_w, f );   //      Width;
        cfwrite_ushort( (ushort)gr_screen.max_h, f );   //      Height;
        cfwrite_ubyte( 24, f ); //PixelDepth;
        cfwrite_ubyte( 0, f );  //ImageDesc;

        buf = (ubyte*)malloc(gr_screen.max_w * gr_screen.max_h * 3);

        if (buf == NULL)
                return;

        memset(buf, 0, gr_screen.max_w * gr_screen.max_h * 3);

        glReadPixels(0, 0, gr_screen.max_w, gr_screen.max_h, GL_BGR, GL_UNSIGNED_BYTE, buf);

        cfwrite(buf, gr_screen.max_w * gr_screen.max_h * 3, 1, f);

        cfclose(f);

        free(buf);
#endif
}

int gr_opengl_supports_res_ingame(int res)
{
        STUB_FUNCTION;
        
        return 1;
}

int gr_opengl_supports_res_interface(int res)
{
        STUB_FUNCTION;
        
        return 1;
}

static void opengl_tcache_cleanup ();

void gr_opengl_cleanup()
{
        if ( !Inited )  return;


        gr_reset_clip();
        gr_clear();
        gr_flip();

        opengl_tcache_cleanup ();

        Inited = 0;
}

void gr_opengl_fog_set(int fog_mode, int r, int g, int b, float fog_near, float fog_far)
{
        Assert((r >= 0) && (r < 256));
        Assert((g >= 0) && (g < 256));
        Assert((b >= 0) && (b < 256));
        
        if (fog_mode == GR_FOGMODE_NONE) {
                if (gr_screen.current_fog_mode != fog_mode) {
                        glDisable(GL_FOG);
                }
                gr_screen.current_fog_mode = fog_mode;
                
                return;
        }
        
        if (gr_screen.current_fog_mode != fog_mode) {
                glEnable(GL_FOG);
                
                if (D3D_fog_mode == 2) {
                        glFogi(GL_FOG_MODE, GL_LINEAR);
                }
                
                gr_screen.current_fog_mode = fog_mode;
        }
        
        if ( (gr_screen.current_fog_color.red != r) ||
                        (gr_screen.current_fog_color.green != g) ||
                        (gr_screen.current_fog_color.blue != b) ) {
                GLfloat fc[4];
                
                gr_opengl_init_color( &gr_screen.current_fog_color, r, g, b );
        
                fc[0] = (float)r/255.0;
                fc[1] = (float)g/255.0;
                fc[2] = (float)b/255.0;
                fc[3] = 1.0;
                
                glFogfv(GL_FOG_COLOR, fc);
        }
        
        if( (fog_near >= 0.0f) && (fog_far >= 0.0f) && 
                        ((fog_near != gr_screen.fog_near) || 
                        (fog_far != gr_screen.fog_far)) ) {
                gr_screen.fog_near = fog_near;
                gr_screen.fog_far = fog_far;
                
                if (D3D_fog_mode == 2) {
                        glFogf(GL_FOG_START, fog_near);
                        glFogf(GL_FOG_END, fog_far);
                }
        }
}

void gr_opengl_get_pixel(int x, int y, int *r, int *g, int *b)
{
        // Not used.
}

void gr_opengl_set_cull(int cull)
{
        if (cull) {
                glEnable (GL_CULL_FACE);
                glFrontFace (GL_CCW);
        } else {
                glDisable (GL_CULL_FACE);
        }
}

void gr_opengl_filter_set(int filter)
{
}

// cross fade
void gr_opengl_cross_fade(int bmap1, int bmap2, int x1, int y1, int x2, int y2, float pct)
{
        gr_set_bitmap(bmap1, GR_ALPHABLEND_FILTER, GR_BITBLT_MODE_NORMAL, 1.0f - pct );
        gr_bitmap(x1, y1);

        gr_set_bitmap(bmap2, GR_ALPHABLEND_FILTER, GR_BITBLT_MODE_NORMAL, pct );
        gr_bitmap(x2, y2);      
}


typedef struct tcache_slot_opengl {
        GLuint  texture_handle;
        float   u_scale, v_scale;
        int     bitmap_id;
        int     size;
        int     used_this_frame;
        int     time_created;
        ushort  w,h;

        // sections
        tcache_slot_opengl      *data_sections[MAX_BMAP_SECTIONS_X][MAX_BMAP_SECTIONS_Y];
        tcache_slot_opengl      *parent;
        
        gr_texture_source       texture_mode;
} tcache_slot_opengl;

static void *Texture_sections = NULL;
static tcache_slot_opengl *Textures = NULL;

static tcache_slot_opengl *GL_bound_texture;

int GL_texture_sections = 0;
int GL_texture_ram = 0;
int GL_frame_count = 0;
int GL_min_texture_width = 0;
int GL_max_texture_width = 0;
int GL_min_texture_height = 0;
int GL_max_texture_height = 0;
int GL_square_textures = 0;
int GL_textures_in = 0;
int GL_textures_in_frame = 0;
int GL_last_bitmap_id = -1;
int GL_last_detail = -1;
int GL_last_bitmap_type = -1;
int GL_last_section_x = -1;
int GL_last_section_y = -1;

int vram_full = 0;

static gr_texture_source GL_current_texture_source = (gr_texture_source) -1;

static void gr_opengl_set_texture_state(gr_texture_source ts)
{
        if (ts == TEXTURE_SOURCE_NONE) {
                GL_bound_texture = NULL;
                                
                glBindTexture(GL_TEXTURE_2D, 0);
                gr_tcache_set(-1, -1, NULL, NULL, 0, -1, -1, 0 );
        } else if (GL_bound_texture &&
                GL_bound_texture->texture_mode != ts) {
                switch (ts) {
                        case TEXTURE_SOURCE_DECAL:
                                glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
                                glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
                                break;
                        case TEXTURE_SOURCE_NO_FILTERING:
                                glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
                                glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
                                break;
                        default:
                                break;
                }
                        
                GL_bound_texture->texture_mode = ts;
        }
        
        GL_current_texture_source = ts;
}

static int opengl_max_tex_size_get()
{
        GLint max_texture_size = 0;

        glGetIntegerv( GL_MAX_TEXTURE_SIZE, &max_texture_size );
        return max_texture_size;
}

static void opengl_tcache_init (int use_sections)
{
        int i, idx, s_idx;

        // DDOI - FIXME skipped a lot of stuff here
        GL_should_preload = 0;

        //uint tmp_pl = os_config_read_uint( NULL, NOX("D3DPreloadTextures"), 255 );
        uint tmp_pl = 1;

        if ( tmp_pl == 0 )      {
                GL_should_preload = 0;
        } else if ( tmp_pl == 1 )       {
                GL_should_preload = 1;
        } else {
                GL_should_preload = 1;
        }

        STUB_FUNCTION;

        GL_min_texture_width = 16;
        GL_min_texture_height = 16;

        GL_max_texture_width = opengl_max_tex_size_get();
        GL_max_texture_height = opengl_max_tex_size_get();

        Textures = (tcache_slot_opengl *)malloc(MAX_BITMAPS*sizeof(tcache_slot_opengl));
        if ( !Textures )        {
                exit(1);
        }

        if(use_sections){
                Texture_sections = (tcache_slot_opengl*)malloc(MAX_BITMAPS * MAX_BMAP_SECTIONS_X * MAX_BMAP_SECTIONS_Y * sizeof(tcache_slot_opengl));
                if(!Texture_sections){
                        exit(1);
                }
                memset(Texture_sections, 0, MAX_BITMAPS * MAX_BMAP_SECTIONS_X * MAX_BMAP_SECTIONS_Y * sizeof(tcache_slot_opengl));
        }

        // Init the texture structures
        int section_count = 0;
        for( i=0; i<MAX_BITMAPS; i++ )  {
                /*
                Textures[i].vram_texture = NULL;
                Textures[i].vram_texture_surface = NULL;
                */
                Textures[i].texture_handle = 0;

                Textures[i].bitmap_id = -1;
                Textures[i].size = 0;
                Textures[i].used_this_frame = 0;

                Textures[i].parent = NULL;

                // allocate sections
                if(use_sections){
                        for(idx=0; idx<MAX_BMAP_SECTIONS_X; idx++){
                                for(s_idx=0; s_idx<MAX_BMAP_SECTIONS_Y; s_idx++){
                                        Textures[i].data_sections[idx][s_idx] = &((tcache_slot_opengl*)Texture_sections)[section_count++];
                                        Textures[i].data_sections[idx][s_idx]->parent = &Textures[i];
                                        /*
                                        Textures[i].data_sections[idx][s_idx]->vram_texture = NULL;
                                        Textures[i].data_sections[idx][s_idx]->vram_texture_surface = NULL;
                                        */
                                        Textures[i].data_sections[idx][s_idx]->texture_handle = 0;
                                        Textures[i].data_sections[idx][s_idx]->bitmap_id = -1;
                                        Textures[i].data_sections[idx][s_idx]->size = 0;
                                        Textures[i].data_sections[idx][s_idx]->used_this_frame = 0;
                                }
                        }
                } else {
                        for(idx=0; idx<MAX_BMAP_SECTIONS_X; idx++){
                                for(s_idx=0; s_idx<MAX_BMAP_SECTIONS_Y; s_idx++){
                                        Textures[i].data_sections[idx][s_idx] = NULL;
                                }
                        }
                }
        }

        GL_texture_sections = use_sections;

        GL_last_detail = Detail.hardware_textures;
        GL_last_bitmap_id = -1;
        GL_last_bitmap_type = -1;

        GL_last_section_x = -1;
        GL_last_section_y = -1;

        GL_textures_in = 0;
        GL_textures_in_frame = 0;
}

static int opengl_free_texture (tcache_slot_opengl *t);

void opengl_free_texture_with_handle(int handle)
{
        for(int i=0; i<MAX_BITMAPS; i++ )  {
                if (Textures[i].bitmap_id == handle) {
                        Textures[i].used_this_frame = 0; // this bmp doesn't even exist any longer...
                        opengl_free_texture ( &Textures[i] );
                }
        }
}

static void opengl_tcache_flush ()
{
        int i;

        for( i=0; i<MAX_BITMAPS; i++ )  {
                opengl_free_texture ( &Textures[i] );
        }
        if (GL_textures_in != 0) {
                mprintf(( "WARNING: VRAM is at %d instead of zero after flushing!\n", GL_textures_in ));
                GL_textures_in = 0;
        }

        GL_last_bitmap_id = -1;
        GL_last_section_x = -1;
        GL_last_section_y = -1;
}

static void opengl_tcache_cleanup ()
{
        opengl_tcache_flush ();

        GL_textures_in = 0;
        GL_textures_in_frame = 0;

        if ( Textures ) {
                free(Textures);
                Textures = NULL;
        }

        if( Texture_sections != NULL ){
                free(Texture_sections);
                Texture_sections = NULL;
        }
}

static void opengl_tcache_frame ()
{
        GL_last_bitmap_id = -1;
        GL_textures_in_frame = 0;

        GL_frame_count++;

        /*
        int idx, s_idx;
        int i;
        for( i=0; i<MAX_BITMAPS; i++ )  {
                Textures[i].used_this_frame = 0;

                // data sections
                if(Textures[i].data_sections[0][0] != NULL){
                        Assert(GL_texture_sections);
                        if(GL_texture_sections){
                                for(idx=0; idx<MAX_BMAP_SECTIONS_X; idx++){
                                        for(s_idx=0; s_idx<MAX_BMAP_SECTIONS_Y; s_idx++){
                                                if(Textures[i].data_sections[idx][s_idx] != NULL){
                                                        Textures[i].data_sections[idx][s_idx]->used_this_frame = 0;
                                                }
                                        }
                                }
                        }
                }
        }
        */

        if ( vram_full )        {
                opengl_tcache_flush();
                vram_full = 0;
        }
}

static int opengl_free_texture ( tcache_slot_opengl *t )
{
        int idx, s_idx;
        

        // Bitmap changed!!     
        if ( t->bitmap_id > -1 )        {
                // if I, or any of my children have been used this frame, bail  
                if(t->used_this_frame == GL_frame_count){
                        return 0;
                }
                for(idx=0; idx<MAX_BMAP_SECTIONS_X; idx++){
                        for(s_idx=0; s_idx<MAX_BMAP_SECTIONS_Y; s_idx++){
                                if((t->data_sections[idx][s_idx] != NULL) && (t->data_sections[idx][s_idx]->used_this_frame == GL_frame_count)){
                                        return 0;
                                }
                        }
                }

                // ok, now we know its legal to free everything safely
                t->texture_mode = (gr_texture_source) -1;
                glDeleteTextures (1, &t->texture_handle);
                t->texture_handle = 0;

                if ( GL_last_bitmap_id == t->bitmap_id )       {
                        GL_last_bitmap_id = -1;
                }

                // if this guy has children, free them too, since the children
                // actually make up his size
                for(idx=0; idx<MAX_BMAP_SECTIONS_X; idx++){
                        for(s_idx=0; s_idx<MAX_BMAP_SECTIONS_Y; s_idx++){
                                if(t->data_sections[idx][s_idx] != NULL){
                                        opengl_free_texture(t->data_sections[idx][s_idx]);
                                }
                        }
                }

                t->bitmap_id = -1;
                t->used_this_frame = 0;
                GL_textures_in -= t->size;
                t->size = 0;
        }

        return 1;
}

static void opengl_tcache_get_adjusted_texture_size(int w_in, int h_in, int *w_out, int *h_out)
{
        int tex_w, tex_h;
        int i;
        
        // bogus
        if((w_out == NULL) ||  (h_out == NULL)){
                return;
        }

        // starting size
        tex_w = w_in;
        tex_h = h_in;

        // set height and width to a power of 2
        for (i=0; i<16; i++ )   {
                if ( (tex_w > (1<<i)) && (tex_w <= (1<<(i+1))) )        {
                        tex_w = 1 << (i+1);
                        break;
                }
        }

        for (i=0; i<16; i++ )   {
                if ( (tex_h > (1<<i)) && (tex_h <= (1<<(i+1))) )        {
                        tex_h = 1 << (i+1);
                        break;
                }
        }

        // try to keep an 8:1 size ratio
        if (tex_w/tex_h > 8)
                tex_h = tex_w/8;
        if (tex_h/tex_w > 8)
                tex_w = tex_h/8;

        if ( tex_w < GL_min_texture_width ) {
                tex_w = GL_min_texture_width;
        } else if ( tex_w > GL_max_texture_width )     {
                tex_w = GL_max_texture_width;
        }

        if ( tex_h < GL_min_texture_height ) {
                tex_h = GL_min_texture_height;
        } else if ( tex_h > GL_max_texture_height )    {
                tex_h = GL_max_texture_height;
        }

        if ( GL_square_textures) {
                int new_size;
                // Make the both be equal to larger of the two
                new_size = max(tex_w, tex_h);
                tex_w = new_size;
                tex_h = new_size;
        }

        // store the outgoing size
        *w_out = tex_w;
        *h_out = tex_h;
}

// data == start of bitmap data
// sx == x offset into bitmap
// sy == y offset into bitmap
// src_w == absolute width of section on source bitmap
// src_h == absolute height of section on source bitmap
// bmap_w == width of source bitmap
// bmap_h == height of source bitmap
// tex_w == width of final texture
// tex_h == height of final texture
static int opengl_create_texture_sub(int bitmap_type, int texture_handle, ushort *data, int sx, int sy, int src_w, int src_h, int bmap_w, int bmap_h, int tex_w, int tex_h, tcache_slot_opengl *t, int reload, int fail_on_full)
{
        int ret_val = 1;
        int size;
        
        // bogus
        if(t == NULL){
                return 0;
        }

        if ( t->used_this_frame == GL_frame_count )       {
                mprintf(( "ARGHH!!! Texture already used this frame!  Cannot free it!\n" ));
                return 0;
        }
        if ( !reload )  {
                // gah
                if(!opengl_free_texture(t)){
                        return 0;
                }
        }

        // get final texture size
        opengl_tcache_get_adjusted_texture_size(tex_w, tex_h, &tex_w, &tex_h);

        if ( (tex_w < 1) || (tex_h < 1) )       {
                mprintf(("Bitmap is to small at %dx%d.\n", tex_w, tex_h ));
                return 0;
        }

        if ( bitmap_type == TCACHE_TYPE_AABITMAP )      {
                t->u_scale = (float)bmap_w / (float)tex_w;
                t->v_scale = (float)bmap_h / (float)tex_h;
        } else if(bitmap_type == TCACHE_TYPE_BITMAP_SECTION){
                t->u_scale = (float)src_w / (float)tex_w;
                t->v_scale = (float)src_h / (float)tex_h;
        } else {
                t->u_scale = 1.0f;
                t->v_scale = 1.0f;
        }

        if (!reload) {
                glGenTextures (1, &t->texture_handle);
        }
        
        if (t->texture_handle == 0) {
                nprintf(("Error", "!!DEBUG!! t->texture_handle == 0"));
                return 0;
        }
                
        GL_bound_texture = t;
        
        GL_bound_texture->texture_mode = (gr_texture_source) -1;
        
        glBindTexture (GL_TEXTURE_2D, t->texture_handle);
        
        glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
        glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
        glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

        /* this should be set next anyway */    
//      if (GL_current_texture_source != TEXTURE_SOURCE_NONE) {
//              gr_opengl_set_texture_state(GL_current_texture_source);
//      }

        size = 0;
                
        switch (bitmap_type) {

                case TCACHE_TYPE_AABITMAP:
                        {
                        int i,j;
                        ubyte *bmp_data = ((ubyte*)data);
                        ubyte *texmem;
                        ubyte *texmemp;
                        
                        ubyte xlat[256];
                        
                        for (i=0; i<16; i++) {
                                xlat[i] = Gr_gamma_lookup[(i*255)/15];
                        }
                        xlat[15] = xlat[1];
                        for ( ; i<256; i++ )    {
                                xlat[i] = xlat[0];
                        }
                        
                        texmem = (ubyte *) malloc (tex_w*tex_h);
                        texmemp = texmem;
                                                        
                        for (i=0;i<tex_h;i++)
                        {
                                for (j=0;j<tex_w;j++)
                                {
                                        if (i < bmap_h && j < bmap_w) {
                                                *texmemp++ = xlat[bmp_data[i*bmap_w+j]];
                                        } else {
                                                *texmemp++ = 0;
                                        }
                                }
                        }

                        size = tex_w*tex_h;
                        
                        if (!reload) {
                                glTexImage2D (GL_TEXTURE_2D, 0, GL_ALPHA, tex_w, tex_h, 0, GL_ALPHA, GL_UNSIGNED_BYTE, texmem);
                        } else {
                                glTexSubImage2D (GL_TEXTURE_2D, 0, 0, 0, tex_w, tex_h, GL_ALPHA, GL_UNSIGNED_BYTE, texmem);
                        }

                        free (texmem);

                        }
                        break;
                case TCACHE_TYPE_BITMAP_SECTION:
                        {
                                int i,j;
                                ubyte *bmp_data = ((ubyte*)data);
                                ubyte *texmem = (ubyte *) malloc (tex_w*tex_h*2);
                                ubyte *texmemp = texmem;
                                
                                for (i=0;i<tex_h;i++)
                                {
                                        for (j=0;j<tex_w;j++)
                                        {
                                                if (i < src_h && j < src_w) {
                                                        *texmemp++ = bmp_data[((i+sy)*bmap_w+(j+sx))*2+0];
                                                        *texmemp++ = bmp_data[((i+sy)*bmap_w+(j+sx))*2+1];
                                                } else {
                                                        *texmemp++ = 0;
                                                        *texmemp++ = 0;
                                                }
                                        }
                                }
                                
                                size = tex_w*tex_h*2;
                                
                                if (!reload) {
                                        glTexImage2D (GL_TEXTURE_2D, 0, GL_RGB5_A1, tex_w, tex_h, 0, GL_BGRA, GL_UNSIGNED_SHORT_1_5_5_5_REV, texmem);
                                } else {
                                        glTexSubImage2D (GL_TEXTURE_2D, 0, 0, 0, tex_w, tex_h, GL_BGRA, GL_UNSIGNED_SHORT_1_5_5_5_REV, texmem);
                                }

                                free(texmem);
                                break;
                        }
                default:
                        {
                                int i,j;
                                ubyte *bmp_data = ((ubyte*)data);
                                ubyte *texmem = (ubyte *) malloc (tex_w*tex_h*2);
                                ubyte *texmemp = texmem;
                                
                                fix u, utmp, v, du, dv;
                                
                                u = v = 0;
                                
                                du = ( (bmap_w-1)*F1_0 ) / tex_w;
                                dv = ( (bmap_h-1)*F1_0 ) / tex_h;
                                
                                for (j=0;j<tex_h;j++)
                                {
                                        utmp = u;
                                        for (i=0;i<tex_w;i++)
                                        {
                                                *texmemp++ = bmp_data[(f2i(v)*bmap_w+f2i(utmp))*2+0];
                                                *texmemp++ = bmp_data[(f2i(v)*bmap_w+f2i(utmp))*2+1];
                                                utmp += du;
                                        }
                                        v += dv;
                                }

                                size = tex_w*tex_h*2;
                                
                                if (!reload) {
                                        glTexImage2D (GL_TEXTURE_2D, 0, GL_RGB5_A1, tex_w, tex_h, 0, GL_BGRA, GL_UNSIGNED_SHORT_1_5_5_5_REV, texmem);
                                } else {
                                        glTexSubImage2D (GL_TEXTURE_2D, 0, 0, 0, tex_w, tex_h, GL_BGRA, GL_UNSIGNED_SHORT_1_5_5_5_REV, texmem);
                                }
                                        
                                free(texmem);
                                break;
                        }
                        break;
        }
        
        t->bitmap_id = texture_handle;
        t->time_created = GL_frame_count;
        t->used_this_frame = 0;
        t->size = size;
        t->w = (ushort)tex_w;
        t->h = (ushort)tex_h;
        
        GL_textures_in_frame += t->size;
        if (!reload) {
                GL_textures_in += t->size;
        }

        return ret_val;
}

static int opengl_create_texture (int bitmap_handle, int bitmap_type, tcache_slot_opengl *tslot, int fail_on_full)
{
        ubyte flags;
        bitmap *bmp;
        int final_w, final_h;
        ubyte bpp = 16;
        int reload = 0;

        // setup texture/bitmap flags
        flags = 0;
        switch(bitmap_type){
                case TCACHE_TYPE_AABITMAP:
                        flags |= BMP_AABITMAP;
                        bpp = 8;
                        break;
                case TCACHE_TYPE_NORMAL:
                        flags |= BMP_TEX_OTHER;
                case TCACHE_TYPE_XPARENT:
                        flags |= BMP_TEX_XPARENT;
                        break;
                case TCACHE_TYPE_NONDARKENING:
                        Int3();
                        flags |= BMP_TEX_NONDARK;
                        break;
        }

        // lock the bitmap into the proper format
        bmp = bm_lock(bitmap_handle, bpp, flags);
        if ( bmp == NULL ) {
                mprintf(("Couldn't lock bitmap %d.\n", bitmap_handle ));
                return 0;
        }

        int max_w = bmp->w;
        int max_h = bmp->h;

        
           // DDOI - TODO
        if ( bitmap_type != TCACHE_TYPE_AABITMAP )      {
                // max_w /= D3D_texture_divider;
                // max_h /= D3D_texture_divider;

                // Detail.debris_culling goes from 0 to 4.
                max_w /= (16 >> Detail.hardware_textures);
                max_h /= (16 >> Detail.hardware_textures);
        }
        

        // get final texture size as it will be allocated as a DD surface
        opengl_tcache_get_adjusted_texture_size(max_w, max_h, &final_w, &final_h); 

        // if this tcache slot has no bitmap
        if ( tslot->bitmap_id < 0) {
                reload = 0;
        }
        // different bitmap altogether - determine if the new one can use the old one's slot
        else if (tslot->bitmap_id != bitmap_handle)     {
                if((final_w == tslot->w) && (final_h == tslot->h)){
                        reload = 1;
                        //ml_printf("Reloading texture %d\n", bitmap_handle);
                } else {
                        reload = 0;
                }
        }

        // call the helper
        int ret_val = opengl_create_texture_sub(bitmap_type, bitmap_handle, (ushort*)bmp->data, 0, 0, bmp->w, bmp->h, bmp->w, bmp->h, max_w, max_h, tslot, reload, fail_on_full);

        // unlock the bitmap
        bm_unlock(bitmap_handle);

        return ret_val;
}

static int opengl_create_texture_sectioned(int bitmap_handle, int bitmap_type, tcache_slot_opengl *tslot, int sx, int sy, int fail_on_full)
{
        ubyte flags;
        bitmap *bmp;
        int final_w, final_h;
        int section_x, section_y;
        int reload = 0;

        // setup texture/bitmap flags
        Assert(bitmap_type == TCACHE_TYPE_BITMAP_SECTION);
        if(bitmap_type != TCACHE_TYPE_BITMAP_SECTION){
                bitmap_type = TCACHE_TYPE_BITMAP_SECTION;
        }
        flags = BMP_TEX_XPARENT;

        // lock the bitmap in the proper format
        bmp = bm_lock(bitmap_handle, 16, flags);
        if ( bmp == NULL ) {
                mprintf(("Couldn't lock bitmap %d.\n", bitmap_handle ));
                return 0;
        }
        // determine the width and height of this section
        bm_get_section_size(bitmap_handle, sx, sy, &section_x, &section_y);

        // get final texture size as it will be allocated as an opengl texture
        opengl_tcache_get_adjusted_texture_size(section_x, section_y, &final_w, &final_h);

        // if this tcache slot has no bitmap
        if ( tslot->bitmap_id < 0) {
                reload = 0;
        }
        // different bitmap altogether - determine if the new one can use the old one's slot
        else if (tslot->bitmap_id != bitmap_handle)     {
                if((final_w == tslot->w) && (final_h == tslot->h)){
                        reload = 1;
                } else {
                        reload = 0;
                }
        }

        // call the helper
        int ret_val = opengl_create_texture_sub(bitmap_type, bitmap_handle, (ushort*)bmp->data, bmp->sections.sx[sx], bmp->sections.sy[sy], section_x, section_y, bmp->w, bmp->h, section_x, section_y, tslot, reload, fail_on_full);

        // unlock the bitmap
        bm_unlock(bitmap_handle);

        return ret_val;
}

                
extern int bm_get_cache_slot( int bitmap_id, int separate_ani_frames );
static int gr_opengl_tcache_set(int bitmap_id, int bitmap_type, float *u_scale, float *v_scale, int fail_on_full = 0, int sx = -1, int sy = -1, int force = 0)
{
        bitmap *bmp = NULL;

        int idx, s_idx;
        int ret_val = 1;

        if (bitmap_id < 0)
        {
                GL_last_bitmap_id = -1;
                return 0;
        }

        if ( GL_last_detail != Detail.hardware_textures )      {
                GL_last_detail = Detail.hardware_textures;
                opengl_tcache_flush();
        }

        if (vram_full) {
                return 0;
        }

        int n = bm_get_cache_slot (bitmap_id, 1);
        tcache_slot_opengl *t = &Textures[n];

        if ( (GL_last_bitmap_id == bitmap_id) && (GL_last_bitmap_type==bitmap_type) && (t->bitmap_id == bitmap_id) && (GL_last_section_x == sx) && (GL_last_section_y == sy))       {
                t->used_this_frame = GL_frame_count;

                // mark all children as used
                if(GL_texture_sections){
                        for(idx=0; idx<MAX_BMAP_SECTIONS_X; idx++){
                                for(s_idx=0; s_idx<MAX_BMAP_SECTIONS_Y; s_idx++){
                                        if(t->data_sections[idx][s_idx] != NULL){
                                                t->data_sections[idx][s_idx]->used_this_frame = GL_frame_count;
                                        }
                                }
                        }
                }

                *u_scale = t->u_scale;
                *v_scale = t->v_scale;
                return 1;
        }

        if (bitmap_type == TCACHE_TYPE_BITMAP_SECTION){
                Assert((sx >= 0) && (sy >= 0) && (sx < MAX_BMAP_SECTIONS_X) && (sy < MAX_BMAP_SECTIONS_Y));
                if(!((sx >= 0) && (sy >= 0) && (sx < MAX_BMAP_SECTIONS_X) && (sy < MAX_BMAP_SECTIONS_Y))){
                        return 0;
                }

                ret_val = 1;

                // if the texture sections haven't been created yet
                if((t->bitmap_id < 0) || (t->bitmap_id != bitmap_id)){

                        // lock the bitmap in the proper format
                        bmp = bm_lock(bitmap_id, 16, BMP_TEX_XPARENT);
                        bm_unlock(bitmap_id);

                        // now lets do something for each texture

                        for(idx=0; idx<bmp->sections.num_x; idx++){
                                for(s_idx=0; s_idx<bmp->sections.num_y; s_idx++){
                                        // hmm. i'd rather we didn't have to do it this way...
                                        if(!opengl_create_texture_sectioned(bitmap_id, bitmap_type, t->data_sections[idx][s_idx], idx, s_idx, fail_on_full)){
                                                ret_val = 0;
                                        }

                                        // not used this frame
                                        t->data_sections[idx][s_idx]->used_this_frame = 0;
                                }
                        }

                        // zero out pretty much everything in the parent struct since he's just the root
                        t->bitmap_id = bitmap_id;
                        t->texture_handle = 0;
                        t->time_created = t->data_sections[sx][sy]->time_created;
                        t->used_this_frame = 0;
                        /*
                        t->vram_texture = NULL;
                        t->vram_texture_surface = NULL
                        */
                }

                // argh. we failed to upload. free anything we can
                if(!ret_val){
                        opengl_free_texture(t);
                }
                // swap in the texture we want
                else {
                        t = t->data_sections[sx][sy];
                }
        }
        // all other "normal" textures
        else if((bitmap_id < 0) || (bitmap_id != t->bitmap_id)){
                ret_val = opengl_create_texture( bitmap_id, bitmap_type, t, fail_on_full );
        }

        // everything went ok
        if(ret_val && (t->texture_handle) && !vram_full){
                *u_scale = t->u_scale;
                *v_scale = t->v_scale;

                GL_bound_texture = t;
                
                glBindTexture (GL_TEXTURE_2D, t->texture_handle );

                /* this should be set next anyway */
//              if (GL_current_texture_source != TEXTURE_SOURCE_NONE) {
//                      gr_opengl_set_texture_state(GL_current_texture_source);
//              }
                
                GL_last_bitmap_id = t->bitmap_id;
                GL_last_bitmap_type = bitmap_type;
                GL_last_section_x = sx;
                GL_last_section_y = sy;

                t->used_this_frame = GL_frame_count;
        }
        // gah
        else {
                GL_last_bitmap_id = -1;
                GL_last_bitmap_type = -1;

                GL_last_section_x = -1;
                GL_last_section_y = -1;

                GL_bound_texture = NULL;
                
                glBindTexture (GL_TEXTURE_2D, 0);       // test - DDOI
                return 0;
        }

        return 1;
}

void gr_opengl_set_clear_color(int r, int g, int b)
{
        gr_init_color (&gr_screen.current_clear_color, r, g, b);
}

void gr_opengl_flash(int r, int g, int b)
{
        CAP(r,0,255);
        CAP(g,0,255);
        CAP(b,0,255);
        
        if ( r || g || b ) {
                gr_opengl_set_state( TEXTURE_SOURCE_NONE, ALPHA_BLEND_ALPHA_ADDITIVE, ZBUFFER_TYPE_NONE );
                
                float x1, x2, y1, y2;
                x1 = i2fl(gr_screen.clip_left+gr_screen.offset_x);
                y1 = i2fl(gr_screen.clip_top+gr_screen.offset_y);
                x2 = i2fl(gr_screen.clip_right+gr_screen.offset_x);
                y2 = i2fl(gr_screen.clip_bottom+gr_screen.offset_y);
                
                glColor4ub(r, g, b, 255);
                glBegin (GL_QUADS);
                  glVertex3f (x1, y2, -0.99);

                  glVertex3f (x2, y2, -0.99);

                  glVertex3f (x2, y1, -0.99);

                  glVertex3f (x1, y1, -0.99);
                glEnd ();         
        }
}

int gr_opengl_zbuffer_get()
{
        if ( !gr_global_zbuffering )    {
                return GR_ZBUFF_NONE;
        }
        return gr_zbuffering_mode;
}

int gr_opengl_zbuffer_set(int mode)
{
        int tmp = gr_zbuffering_mode;

        gr_zbuffering_mode = mode;

        if (gr_zbuffering_mode == GR_ZBUFF_NONE )      {
                gr_zbuffering = 0;
        } else {
                gr_zbuffering = 1;
        }
        return tmp;
}

void gr_opengl_zbuffer_clear(int mode)
{
        if (mode) {
                gr_zbuffering = 1;
                gr_zbuffering_mode = GR_ZBUFF_FULL;
                gr_global_zbuffering = 1;
                
                gr_opengl_set_state( TEXTURE_SOURCE_NONE, ALPHA_BLEND_NONE, ZBUFFER_TYPE_FULL );
                glClear ( GL_DEPTH_BUFFER_BIT );
        } else {
                gr_zbuffering = 0;
                gr_zbuffering_mode = GR_ZBUFF_NONE;
                gr_global_zbuffering = 0;
        }
}

void gr_opengl_set_gamma(float gamma)
{
        Gr_gamma = gamma;
        Gr_gamma_int = int (Gr_gamma*10);

        // Create the Gamma lookup table
        int i;
        for (i=0;i<256; i++) {
                int v = fl2i(pow(i2fl(i)/255.0f, 1.0f/Gr_gamma)*255.0f);
                if ( v > 255 ) {
                        v = 255;
                } else if ( v < 0 )     {
                        v = 0;
                }
                Gr_gamma_lookup[i] = v;
        }

        // Flush any existing textures
        opengl_tcache_flush();
}

void gr_opengl_fade_in(int instantaneous)
{
        // Empty - DDOI
}

void gr_opengl_fade_out(int instantaneous)
{
        // Empty - DDOI
}

void gr_opengl_get_region(int front, int w, int h, ubyte *data)
{
        if (front) {
                glReadBuffer(GL_FRONT);
        } else {
                glReadBuffer(GL_BACK);
        }
        
        gr_opengl_set_state(TEXTURE_SOURCE_NO_FILTERING, ALPHA_BLEND_NONE, ZBUFFER_TYPE_NONE);
        
        glPixelStorei(GL_UNPACK_ROW_LENGTH, gr_screen.max_w);
        
        if (gr_screen.bits_per_pixel == 15) {
                glReadPixels(0, gr_screen.max_h-h-1, w, h, GL_BGRA, GL_UNSIGNED_SHORT_1_5_5_5_REV, data);
        } else if (gr_screen.bits_per_pixel == 32) {
                glReadPixels(0, gr_screen.max_h-h-1, w, h, GL_RGBA, GL_UNSIGNED_BYTE, data);
        }
        
        glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
}

static int Gr_opengl_mouse_saved = 0;
static int Gr_opengl_mouse_saved_x1 = 0;
static int Gr_opengl_mouse_saved_y1 = 0;
static int Gr_opengl_mouse_saved_x2 = 0;
static int Gr_opengl_mouse_saved_y2 = 0;
static int Gr_opengl_mouse_saved_w = 0;
static int Gr_opengl_mouse_saved_h = 0;
#define MAX_SAVE_SIZE (32*32)
static ubyte Gr_opengl_mouse_saved_data[MAX_SAVE_SIZE*2];

#define CLAMP(x,r1,r2) do { if ( (x) < (r1) ) (x) = (r1); else if ((x) > (r2)) (x) = (r2); } while(0)

void gr_opengl_save_mouse_area(int x, int y, int w, int h)
{
        Gr_opengl_mouse_saved_x1 = x;
        Gr_opengl_mouse_saved_y1 = y;
        Gr_opengl_mouse_saved_x2 = x+w-1;
        Gr_opengl_mouse_saved_y2 = y+h-1;
        
        CLAMP(Gr_opengl_mouse_saved_x1, gr_screen.clip_left, gr_screen.clip_right );
        CLAMP(Gr_opengl_mouse_saved_x2, gr_screen.clip_left, gr_screen.clip_right );
        CLAMP(Gr_opengl_mouse_saved_y1, gr_screen.clip_top, gr_screen.clip_bottom );
        CLAMP(Gr_opengl_mouse_saved_y2, gr_screen.clip_top, gr_screen.clip_bottom );
        
        Gr_opengl_mouse_saved_w = Gr_opengl_mouse_saved_x2 - Gr_opengl_mouse_saved_x1 + 1;
        Gr_opengl_mouse_saved_h = Gr_opengl_mouse_saved_y2 - Gr_opengl_mouse_saved_y1 + 1;

        if ( Gr_opengl_mouse_saved_w < 1 ) return;
        if ( Gr_opengl_mouse_saved_h < 1 ) return;
        
        Assert( (Gr_opengl_mouse_saved_w*Gr_opengl_mouse_saved_h) <= MAX_SAVE_SIZE );

        gr_opengl_set_state(TEXTURE_SOURCE_NO_FILTERING, ALPHA_BLEND_NONE, ZBUFFER_TYPE_NONE);
        
        glReadBuffer(GL_BACK);
        glReadPixels(x, gr_screen.max_h-y-1-h, w, h, GL_BGRA, GL_UNSIGNED_SHORT_1_5_5_5_REV, Gr_opengl_mouse_saved_data);
        
        Gr_opengl_mouse_saved = 1;
}

int gr_opengl_save_screen()
{
        gr_reset_clip();

        if ( Gr_saved_screen )  {
                mprintf(( "Screen alread saved!\n" ));
                return -1;
        }

        Gr_saved_screen = (char*)malloc( gr_screen.max_w * gr_screen.max_h * gr_screen.bytes_per_pixel );
        if (!Gr_saved_screen) {
                mprintf(( "Couldn't get memory for saved screen!\n" ));
                return -1;
        }

        char *Gr_saved_screen_tmp = (char*)malloc( gr_screen.max_w * gr_screen.max_h * gr_screen.bytes_per_pixel );
        if (!Gr_saved_screen_tmp) {
                mprintf(( "Couldn't get memory for temporary saved screen!\n" ));
                return -1;
        }
        
        gr_opengl_set_state(TEXTURE_SOURCE_NO_FILTERING, ALPHA_BLEND_NONE, ZBUFFER_TYPE_NONE);
        
        glReadBuffer(GL_FRONT);
        glReadPixels(0, 0, gr_screen.max_w, gr_screen.max_h, GL_BGRA, GL_UNSIGNED_SHORT_1_5_5_5_REV, Gr_saved_screen_tmp);
        
        ubyte *sptr, *dptr;
        
        sptr = (ubyte *)&Gr_saved_screen_tmp[gr_screen.max_w*gr_screen.max_h*2];
        dptr = (ubyte *)Gr_saved_screen;
        for (int j = 0; j < gr_screen.max_h; j++) {
                sptr -= gr_screen.max_w*2;
                memcpy(dptr, sptr, gr_screen.max_w*2);
                dptr += gr_screen.max_w*2;
        }
        
        free(Gr_saved_screen_tmp);
        
        if (Gr_opengl_mouse_saved) {
                sptr = (ubyte *)Gr_opengl_mouse_saved_data;
                dptr = (ubyte *)&Gr_saved_screen[2*(Gr_opengl_mouse_saved_x1+(Gr_opengl_mouse_saved_y2)*gr_screen.max_w)];
                for (int i = 0; i < Gr_opengl_mouse_saved_h; i++) {
                        memcpy(dptr, sptr, Gr_opengl_mouse_saved_w*2);
                
                        sptr += 32*2;
                        dptr -= gr_screen.max_w*2;
                }
        }

        // this leaks texture handles, and the opengl doesn't currently 
        // perform some sort of garbage collection, so a hack was added
        // to bmpman to make it free textures when released
        Gr_saved_screen_bitmap = bm_create(16, gr_screen.max_w, gr_screen.max_h, Gr_saved_screen, 0);
        
        return Gr_saved_screen_bitmap;
}

void gr_opengl_restore_screen(int id)
{
        gr_reset_clip();
        
        if ( !Gr_saved_screen ) {
                gr_clear();
                return;
        }

        gr_opengl_set_state(TEXTURE_SOURCE_NO_FILTERING, ALPHA_BLEND_NONE, ZBUFFER_TYPE_NONE);
        
        gr_set_bitmap(Gr_saved_screen_bitmap, GR_ALPHABLEND_NONE, GR_BITBLT_MODE_NORMAL, 1.0f, -1, -1);
        gr_bitmap(0, 0);                
}

void gr_opengl_free_screen(int id)
{
        bm_release(Gr_saved_screen_bitmap);
        
        if ( Gr_saved_screen )  {
                free( Gr_saved_screen );
                Gr_saved_screen = NULL;
        }
}

void gr_opengl_dump_frame_start(int first_frame, int frames_between_dumps)
{
        STUB_FUNCTION;
}

void gr_opengl_dump_frame_stop()
{
        STUB_FUNCTION;
}

void gr_opengl_dump_frame()
{
        STUB_FUNCTION;
}

uint gr_opengl_lock()
{
        STUB_FUNCTION;
        
        return 1;
}
        
void gr_opengl_unlock()
{
}

void opengl_zbias(int bias)
{
        if (bias) {
                glEnable(GL_POLYGON_OFFSET_FILL);
                glPolygonOffset(0.0, -bias);
        } else {
                glDisable(GL_POLYGON_OFFSET_FILL);
        }
}
                
extern char *Osreg_title;
void gr_opengl_init()
{
        if ( Inited )   {
                gr_opengl_cleanup();
                Inited = 0;
        }

        mprintf(( "Initializing opengl graphics device...\n" ));
        Inited = 1;

#ifdef PLAT_UNIX        
        if (SDL_InitSubSystem (SDL_INIT_VIDEO) < 0)
        {
                fprintf (stderr, "Couldn't init SDL: %s", SDL_GetError());
                exit (1);
        }

        SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 5);
        SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 5);
        SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 5);
        SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 16);
        SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
        
        int flags = SDL_OPENGL;
        
        if (!Cmdline_window && ( (os_config_read_uint( NULL, "Fullscreen", 1 ) == 1) || Cmdline_fullscreen ))
                flags |= SDL_FULLSCREEN;

        // grab mouse/key unless told otherwise, ignore when we are going fullscreen
        if ( !((flags & SDL_FULLSCREEN) || Cmdline_no_grab) ) {
                SDL_WM_GrabInput(SDL_GRAB_ON);
        }

        FSAA = os_config_read_uint( NULL, "FSAA", 1 );
        if ( FSAA ) {
            SDL_GL_SetAttribute( SDL_GL_MULTISAMPLEBUFFERS, 1 );
            SDL_GL_SetAttribute( SDL_GL_MULTISAMPLESAMPLES, FSAA );
        }
        
        if (SDL_SetVideoMode (gr_screen.max_w, gr_screen.max_h,0,flags) == NULL)
        {
            mprintf(( "Couldn't set FSAA video mode: %s\n", SDL_GetError () ));
            SDL_GL_SetAttribute( SDL_GL_MULTISAMPLEBUFFERS, 0 );
            SDL_GL_SetAttribute( SDL_GL_MULTISAMPLESAMPLES, 0 );
                
            if (SDL_SetVideoMode (gr_screen.max_w, gr_screen.max_h,0,flags) == NULL)
            {
                    fprintf (stderr, "Couldn't set video mode: %s\n", SDL_GetError ());
                    exit (1);
            }
        }

        mprintf(( "Screen BPP: %d\n", SDL_GetVideoSurface()->format->BitsPerPixel ));
        mprintf(( "\n" ));
        mprintf(( "Vendor     : %s\n", glGetString(GL_VENDOR) ));
        mprintf(( "Renderer   : %s\n", glGetString(GL_RENDERER) ));
        mprintf(( "Version    : %s\n", glGetString(GL_VERSION) ));

#ifndef NDEBUG
        // print out extensions - taken from FS2_Open (credits: phreak, taylor)
        mprintf(( "Extensions : \n"));

        static const char *OGL_extensions = (const char*)glGetString(GL_EXTENSIONS);

        // we use the "+1" here to have an extra NULL char on the end (with the memset())
        // this is to fix memory errors when the last char in extlist is the same as the token
        // we are looking for and ultra evil strtok() may still return non-NULL at EOS
        char *extlist = (char*)malloc(strlen(OGL_extensions) + 1);
        memset(extlist, 0, strlen(OGL_extensions) + 1);

        if (extlist != NULL) {
                memcpy(extlist, OGL_extensions, strlen(OGL_extensions));

                char *curext = strtok(extlist, " ");

                while (curext) {
                        mprintf(( "     %s\n", curext ));
                        curext = strtok(NULL, " ");
                }

                free(extlist);
                extlist = NULL;
        }

        mprintf(( "\n" ));
#endif
        
        int value;
        int rgb_size[3];
        int bpp = 15;
        rgb_size[0]=5;
        rgb_size[1]=5;
        rgb_size[2]=5;

        SDL_GL_GetAttribute( SDL_GL_RED_SIZE, &value );
        mprintf(( "SDL_GL_RED_SIZE: requested %d, got %d\n", rgb_size[0],value ));
        SDL_GL_GetAttribute( SDL_GL_GREEN_SIZE, &value );
        mprintf(( "SDL_GL_GREEN_SIZE: requested %d, got %d\n", rgb_size[1],value ));
        SDL_GL_GetAttribute( SDL_GL_BLUE_SIZE, &value );
        mprintf(( "SDL_GL_BLUE_SIZE: requested %d, got %d\n", rgb_size[2],value ));
        SDL_GL_GetAttribute( SDL_GL_DEPTH_SIZE, &value );
        mprintf(( "SDL_GL_DEPTH_SIZE: requested %d, got %d\n", bpp, value ));
        SDL_GL_GetAttribute( SDL_GL_DOUBLEBUFFER, &value );
        mprintf(( "SDL_GL_DOUBLEBUFFER: requested 1, got %d\n", value ));

        if ( FSAA ) {
                SDL_GL_GetAttribute( SDL_GL_MULTISAMPLEBUFFERS, &value );
                mprintf(( "SDL_GL_MULTISAMPLEBUFFERS: requested 1, got %d\n", value ));
                SDL_GL_GetAttribute( SDL_GL_MULTISAMPLESAMPLES, &value );
                mprintf(( "SDL_GL_MULTISAMPLESAMPLES: requested %d, got %d\n", FSAA, value ));
        }

        SDL_ShowCursor(0);
        SDL_WM_SetCaption (Osreg_title, NULL);
        
        /* might as well put this here */
        SDL_EnableKeyRepeat(SDL_DEFAULT_REPEAT_DELAY, SDL_DEFAULT_REPEAT_INTERVAL);
#endif

        GL_use_luminance_alpha = os_config_read_uint(NOX("OpenGL"), NOX("UseLuminanceAlpha"), 0);

        glViewport(0, 0, gr_screen.max_w, gr_screen.max_h);

        glMatrixMode(GL_PROJECTION);
        glLoadIdentity();
        glOrtho(0, gr_screen.max_w, gr_screen.max_h, 0, 0.0, 1.0);
        glMatrixMode(GL_MODELVIEW);
        glLoadIdentity();
        
        glShadeModel(GL_SMOOTH);
        glEnable(GL_DITHER);
        glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
        glHint(GL_FOG_HINT, GL_NICEST);
                
        glEnable(GL_DEPTH_TEST);
        glEnable(GL_BLEND);
        
        glEnable(GL_TEXTURE_2D);
        
        glDepthRange(0.0, 1.0);
        
        glPixelStorei(GL_PACK_ALIGNMENT, 1);
        glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
        
        D3D_32bit = 1;              // grd3d.cpp
        extern int D3D_enabled;
        D3D_enabled = 1;
        /* 
          TODO: set fog_mode to 1 if EXT_secondary_color found and wanted 
          1 = use secondary color ext
          2 = use opengl linear fog
         */
        D3D_fog_mode = 2;          // grd3d.cpp

        glFlush();
        
        Bm_pixel_format = BM_PIXEL_FORMAT_ARGB;
        Gr_bitmap_poly = 1;
        
        switch( bpp )   {
        case 15:
                gr_screen.bits_per_pixel = 15;
                gr_screen.bytes_per_pixel = 2;
                
                Gr_red.bits = 5;
                Gr_red.shift = 10;
                Gr_red.scale = 8;
                Gr_red.mask = 0x7C00;

                Gr_green.bits = 5;
                Gr_green.shift = 5;
                Gr_green.scale = 8;
                Gr_green.mask = 0x3E0;

                Gr_blue.bits = 5;
                Gr_blue.shift = 0;
                Gr_blue.scale = 8;
                Gr_blue.mask = 0x1F;

                break;

        case 16:
                gr_screen.bits_per_pixel = 16;
                gr_screen.bytes_per_pixel = 2;
                
                Gr_red.bits = 5;
                Gr_red.shift = 11;
                Gr_red.scale = 8;
                Gr_red.mask = 0xF800;

                Gr_green.bits = 6;
                Gr_green.shift = 5;
                Gr_green.scale = 4;
                Gr_green.mask = 0x7E0;

                Gr_blue.bits = 5;
                Gr_blue.shift = 0;
                Gr_blue.scale = 8;
                Gr_blue.mask = 0x1F;

                break;

        case 32:
                gr_screen.bits_per_pixel = 32;
                gr_screen.bytes_per_pixel = 4;
                
                Gr_red.bits = 8;
                Gr_red.shift = 16;
                Gr_red.scale = 1;
                Gr_red.mask = 0xff0000;

                Gr_green.bits = 8;
                Gr_green.shift = 8;
                Gr_green.scale = 1;
                Gr_green.mask = 0xff00;

                Gr_blue.bits = 8;
                Gr_blue.shift = 0;
                Gr_blue.scale = 1;
                Gr_blue.mask = 0xff;

                break;

        default:
                Int3(); // Illegal bpp
        }

        // DDOI - set these so no one else does!
        Gr_t_red.mask = Gr_red.mask;
        Gr_t_red.shift = Gr_red.shift;
        Gr_t_red.scale = Gr_red.scale;

        Gr_t_green.mask = Gr_green.mask;
        Gr_t_green.shift = Gr_green.shift;
        Gr_t_green.scale = Gr_green.scale;
        
        Gr_t_blue.mask = Gr_blue.mask;
        Gr_t_blue.shift = Gr_blue.shift;
        Gr_t_blue.scale = Gr_blue.scale;
        
        Gr_t_alpha.mask = 0x8000;
        Gr_t_alpha.scale = 255;
        Gr_t_alpha.shift = 15;

        Gr_ta_red.mask = 0x0f00;
        Gr_ta_red.shift = 8;
        Gr_ta_red.scale = 16;

        Gr_ta_green.mask = 0x00f0;
        Gr_ta_green.shift = 4;
        Gr_ta_green.scale = 16;
        
        Gr_ta_blue.mask = 0x000f;
        Gr_ta_blue.shift = 0;
        Gr_ta_blue.scale = 16;

        Gr_ta_alpha.mask = 0xf000;
        Gr_ta_alpha.shift = 12;
        Gr_ta_alpha.scale = 16;


        opengl_tcache_init (1);
        gr_opengl_clear();

        Gr_current_red = &Gr_red;
        Gr_current_blue = &Gr_blue;
        Gr_current_green = &Gr_green;
        Gr_current_alpha = &Gr_alpha;

        gr_screen.gf_flip = gr_opengl_flip;
        gr_screen.gf_flip_window = gr_opengl_flip_window;
        gr_screen.gf_set_clip = gr_opengl_set_clip;
        gr_screen.gf_reset_clip = gr_opengl_reset_clip;
        gr_screen.gf_set_font = grx_set_font;
        
        gr_screen.gf_set_color = gr_opengl_set_color;
        gr_screen.gf_set_bitmap = gr_opengl_set_bitmap;
        gr_screen.gf_create_shader = gr_opengl_create_shader;
        gr_screen.gf_set_shader = gr_opengl_set_shader;
        gr_screen.gf_clear = gr_opengl_clear;
        // gr_screen.gf_bitmap = gr_opengl_bitmap;
        // gr_screen.gf_bitmap_ex = gr_opengl_bitmap_ex;
        gr_screen.gf_aabitmap = gr_opengl_aabitmap;
        gr_screen.gf_aabitmap_ex = gr_opengl_aabitmap_ex;
        
        gr_screen.gf_rect = gr_opengl_rect;
        gr_screen.gf_shade = gr_opengl_shade;
        gr_screen.gf_string = gr_opengl_string;
        gr_screen.gf_circle = gr_opengl_circle;

        gr_screen.gf_line = gr_opengl_line;
        gr_screen.gf_aaline = gr_opengl_aaline;
        gr_screen.gf_pixel = gr_opengl_pixel;
        gr_screen.gf_scaler = gr_opengl_scaler;
        gr_screen.gf_tmapper = gr_opengl_tmapper;

        gr_screen.gf_gradient = gr_opengl_gradient;

        gr_screen.gf_set_palette = gr_opengl_set_palette;
        gr_screen.gf_get_color = gr_opengl_get_color;
        gr_screen.gf_init_color = gr_opengl_init_color;
        gr_screen.gf_init_alphacolor = gr_opengl_init_alphacolor;
        gr_screen.gf_set_color_fast = gr_opengl_set_color_fast;
        gr_screen.gf_print_screen = gr_opengl_print_screen;

        gr_screen.gf_fade_in = gr_opengl_fade_in;
        gr_screen.gf_fade_out = gr_opengl_fade_out;
        gr_screen.gf_flash = gr_opengl_flash;
        
        gr_screen.gf_zbuffer_get = gr_opengl_zbuffer_get;
        gr_screen.gf_zbuffer_set = gr_opengl_zbuffer_set;
        gr_screen.gf_zbuffer_clear = gr_opengl_zbuffer_clear;
        
        gr_screen.gf_save_screen = gr_opengl_save_screen;
        gr_screen.gf_restore_screen = gr_opengl_restore_screen;
        gr_screen.gf_free_screen = gr_opengl_free_screen;
        
        gr_screen.gf_dump_frame_start = gr_opengl_dump_frame_start;
        gr_screen.gf_dump_frame_stop = gr_opengl_dump_frame_stop;
        gr_screen.gf_dump_frame = gr_opengl_dump_frame;
        
        gr_screen.gf_set_gamma = gr_opengl_set_gamma;
        
        gr_screen.gf_lock = gr_opengl_lock;
        gr_screen.gf_unlock = gr_opengl_unlock;
        
        gr_screen.gf_fog_set = gr_opengl_fog_set;       

        gr_screen.gf_get_region = gr_opengl_get_region;

        gr_screen.gf_get_pixel = gr_opengl_get_pixel;

        gr_screen.gf_set_cull = gr_opengl_set_cull;

        gr_screen.gf_cross_fade = gr_opengl_cross_fade;

        gr_screen.gf_filter_set = gr_opengl_filter_set;

        gr_screen.gf_tcache_set = gr_opengl_tcache_set;

        gr_screen.gf_set_clear_color = gr_opengl_set_clear_color;
        
        Mouse_hidden++;
        gr_reset_clip();
        gr_clear();
        gr_flip();
        Mouse_hidden--;
}