get rid of some platform specific stuff

[taylor/freespace2.git] / src / graphics / grglidetexture.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/GrGlideTexture.cpp $
 * $Revision$
 * $Date$
 * $Author$
 *
 * Code to manage Glide texture RAM
 *
 * $Log$
 * Revision 1.2  2002/06/09 04:41:17  relnev
 * added copyright header
 *
 * Revision 1.1.1.1  2002/05/03 03:28:09  root
 * Initial import.
 *
 * 
 * 14    10/13/99 9:22a Daveb
 * Fixed Fred jumpnode placing bug. Fixed 1024 glide tiled texture problem
 * related to movies. Fixed launcher spawning from PXO screen.
 * 
 * 13    7/16/99 1:49p Dave
 * 8 bit aabitmaps. yay.
 * 
 * 12    7/13/99 1:15p Dave
 * 32 bit support. Whee!
 * 
 * 11    7/09/99 9:51a Dave
 * Added thick polyline code.
 * 
 * 10    7/08/99 8:10a Mikek
 * Suppress compiler warning.  Now I get an FS2 programming credit! :)
 * 
 * 9     6/29/99 4:16p Dave
 * Temporary speedup for tcache init.
 * 
 * 8     6/29/99 10:35a Dave
 * Interface polygon bitmaps! Whee!
 * 
 * 7     6/16/99 4:06p Dave
 * New pilot info popup. Added new draw-bitmap-as-poly function.
 * 
 * 6     2/08/99 5:07p Dave
 * FS2 chat server support. FS2 specific validated missions.
 * 
 * 5     1/15/99 11:29a Neilk
 * Fixed D3D screen/texture pixel formatting problem. 
 * 
 * 4     12/01/98 8:06a Dave
 * Temporary checkin to fix some texture transparency problems in d3d.
 * 
 * 3     11/30/98 1:07p Dave
 * 16 bit conversion, first run.
 * 
 * 2     10/07/98 10:53a Dave
 * Initial checkin.
 * 
 * 1     10/07/98 10:49a Dave
 * 
 * 18    5/14/98 5:39p John
 * Added in code for multiple non-dimming lights.
 * 
 * 17    4/27/98 9:33p John
 * Removed mprintf
 * 
 * 16    4/27/98 9:25p John
 * Made Glide skip any 2MB boundry, not just first one.
 * 
 * 15    4/27/98 9:09p John
 * Fixed bug where texture was crossing a 2MB line on Voodoo2.  Added code
 * to tell how full VRAM is and how much got paged in each frame.
 * 
 * 14    4/27/98 10:44a John
 * Put in a new texture caching algorithm that doesn't flush everything
 * every so oftem.
 * 
 * 13    4/26/98 12:02p John
 * Made glide texturing do its own allocation rather than using the gu_
 * functions.
 * 
 * 12    4/26/98 11:14a John
 * Restructured/Cleaned up the caching code in preparation for the new
 * improved caching system.
 * 
 * 11    4/22/98 9:13p John
 * Added code to replace frames of animations in vram if so desired.
 * 
 * 10    4/21/98 9:16a John
 * Fixed bug with directives display in Glide.
 * 
 * 9     4/20/98 8:41p John
 * Made debris culling actually reduce Glide texture resolution.
 * 
 * 8     4/09/98 4:38p John
 * Made non-darkening and transparent textures work under Glide.  Fixed
 * bug with Jim's computer not drawing any bitmaps.
 * 
 * 7     4/09/98 2:21p John
 * Fixed transparency bug with Glide
 * 
 * 6     4/08/98 9:16p John
 * Made transparency work for textures in Glide by using chromakey.  Made
 * nondarkening colors work.
 * 
 * 5     4/08/98 8:47a John
 * Moved all texture caching into a new module
 * 
 * 4     4/06/98 4:45p John
 * Removed some debug code that made textures 2x too small.
 * 
 * 3     3/04/98 5:43p Hoffoss
 * Fixed warning.
 * 
 * 2     3/04/98 3:50p John
 * Made the Glide texture cache manager of Leighton's work with 256x256
 * maps.
 * 
 * 1     3/03/98 4:42p John
 * Added in Leighton's code to do texture caching on Glide.
 *
 * $NoKeywords: $
 */

//#define USE_8BPP_TEXTURES 

#include <windows.h>
#include <windowsx.h>
#include "glide.h"
#include "glideutl.h"

#include "osapi.h"
#include "2d.h"
#include "bmpman.h"
#include "floating.h"
#include "palman.h"
#include "grinternal.h"
#include "grglide.h"
#include "line.h"
#include "font.h"
#include "mouse.h"
#include "key.h"
#include "systemvars.h"
#include "grglideinternal.h"

#define TEXMEM_2MB_EDGE (2*1024*1024)

// Hardware specific values
typedef struct tcache_data {
        GrLOD_t           lod;
        GrAspectRatio_t   aspect;
        GrTextureFormat_t format;
        uint                                    vram_offset;
        int                                     vram_size;      
} tcache_data;

typedef struct tcache_slot {
        int                             bitmap_id;      
        float                           uscale;
        float                           vscale;
        
        tcache_data             data;
        tcache_slot             *data_sections[MAX_BMAP_SECTIONS_X][MAX_BMAP_SECTIONS_Y];               // NULL if no subsections are present. 
        tcache_slot             *parent;
} tcache_slot;

#define MAX_AUX_TEXTURES                                                200
#define MAX_TEXTURES                                                            MAX_BITMAPS

// search for AUX to find all instancees of aux textures which can be put back in.

// AUX
// static tcache_slot *Textures_aux = NULL;                                                                                                             // auxiliary textures for storing sections of a texture
static void *Texture_sections = NULL;
static tcache_slot *Textures = NULL;
ubyte *Glide_tmp_ram = NULL;

int Glide_last_bitmap_id = -1;
int Glide_last_bitmap_type = -1;
int Glide_last_section_x = -1;
int Glide_last_section_y = -1;
float Glide_last_u_ratio, Glide_last_v_ratio;

static int Glide_last_detail = -1;

uint Glide_total_memory;
uint Glide_start_address;
uint Glide_end_address;
uint Glide_current_address;

int Glide_textures_in_frame = 0;

int Glide_explosion_vram = 0;

//=======================================================
// Code to manage texture memory.   
// This basically allocates until out of VRAM, and then starts freeing 
// blocks at the start of VRAM to make room for new textures.   
// Based on code from Jason Scannell's webpage.
// http://members.home.net/jscannell.  

typedef struct  { 
        int             next; 
        uint            start_address; 
        int             size;
        tcache_slot             *texture_ptr;
} tblock; 

tblock  *Tblocks = NULL;                // Memory tracking blocks 
int             Tblock_num_blocks = 0;          // How many blocks to use

int Tblock_freelist_start;                              // First block in free list 
int Tblock_usedlist_start;                              // First block in allocation list 
int Tblock_usedlist_head;                               // Last block in allocation list 

uint Tblock_min_address;                                // Lowest address in texture memory 
uint Tblock_max_address;                                // Highest address in texture memory 

void FlushBlocks()
{
        int i;

        memset(Tblocks,0,sizeof(tblock)*Tblock_num_blocks); 

        for(i = 0; i < Tblock_num_blocks - 1; i++)      {
                Tblocks[i].next = i + 1; 
        }

        Tblocks[Tblock_num_blocks - 1].next = -1; 

        Tblock_usedlist_start = -1; 
        Tblock_usedlist_head  = -1; 
        Tblock_freelist_start  = 0; 
}

void InitBlocks(uint min, uint max, int num_blocks) 
{ 
        Tblock_num_blocks = num_blocks;
        Tblock_min_address = min;
        Tblock_max_address = max;

        if(Tblocks == NULL){
                Tblocks = (tblock *)malloc(Tblock_num_blocks*sizeof(tblock));
                SDL_assert(Tblocks!=NULL);
        }

        FlushBlocks();
} 

void ReleaseBlocks()
{
        if ( Tblocks )  {
                free(Tblocks);
                Tblocks = NULL;
        }
        Tblock_num_blocks = 0;
}

void ReleaseSlotSub(tcache_slot *t)
{
        int idx, s_idx;

        if(t == NULL){
                return;
        }

        t->bitmap_id = -1;
        for(idx=0; idx<MAX_BMAP_SECTIONS_X; idx++){
                for(s_idx=0; s_idx<MAX_BMAP_SECTIONS_Y; s_idx++){
                        // recurse
                        if(t->data_sections[idx][s_idx] != NULL){                               
                                ReleaseSlotSub(t->data_sections[idx][s_idx]);
                                t->data_sections[idx][s_idx] = NULL;
                        }
                }
        }
}

void ReleaseSlot(int nBlock)
{
        if ( Tblocks[nBlock].texture_ptr != NULL )      {                               
                // if this guy has a parent (in the case of a sectioned bitmap), unset his bitmap
                if(Tblocks[nBlock].texture_ptr->parent != NULL){
                        Tblocks[nBlock].texture_ptr->parent->bitmap_id = -1;
                }
                Tblocks[nBlock].texture_ptr->bitmap_id = -1;

                // AUX
                // ReleaseSlotSub(Tblocks[nBlock].texture_ptr);
                Tblocks[nBlock].texture_ptr = NULL;
                

                Glide_textures_in -= Tblocks[nBlock].size;
        }
}

void FreeBlock(int nBlock) 
{ 
        int nFreeNext; 

        ReleaseSlot(nBlock);

        //---- Save next indices ---- 
        nFreeNext = Tblock_freelist_start; 

        //---- Move alloc list block to start of free list ---- 
        Tblock_freelist_start = nBlock; 
        Tblocks[nBlock].next = nFreeNext; 

} 

int AllocBlock(void) 
{ 
        int     nNewBlock; 

        //---- Get block from free list ---- 
        nNewBlock = Tblock_freelist_start; 

        //**** DOS NOT HANDLE EMPTY FREE LIST **** 
        Tblock_freelist_start = Tblocks[Tblock_freelist_start].next; 

        if(Tblock_usedlist_head < 0)    { 
                //---- Alloc list is empty, add to start ---- 
                Tblock_usedlist_start = nNewBlock; 
                Tblocks[nNewBlock].next = -1; 
        } else { 
                //---- Insert at head of alloc list ---- 
                Tblocks[nNewBlock].next = Tblocks[Tblock_usedlist_head].next; 
                Tblocks[Tblock_usedlist_head].next = nNewBlock; 
        } 

        //---- Set new head index ---- 
        Tblock_usedlist_head = nNewBlock; 

        return nNewBlock; 
} 

// Macro to compute ending address of block 
#define BLOCK_END(b) (Tblocks[b].start_address + Tblocks[b].size) 

uint AllocateTexture(uint size, tcache_slot *texture_ptr)
{ 
        int     nNewBlock; 
        int     next; 

        if (Tblock_usedlist_start < 0)  { 

                //---- Alloc list is empty ---- 
                nNewBlock = AllocBlock(); 
                Tblocks[nNewBlock].start_address = Tblock_min_address; 
        } else { 

                uint dwAddress = BLOCK_END(Tblock_usedlist_head);
                if ( dwAddress + size < Tblock_max_address )    {
                        int a1 = dwAddress / TEXMEM_2MB_EDGE;
                        int a2 = (dwAddress+size) / TEXMEM_2MB_EDGE;
        
                        if ( a2 > a1 )  {
                                //mprintf(( "GrGlideTexture: Skipping a 2MB edge!\n" ));
                                dwAddress = a2*TEXMEM_2MB_EDGE;
                        }
                }

                if( (dwAddress + size > Tblock_max_address) || (Tblocks[Tblock_freelist_start].next<0) )        { 
                        #ifndef NDEBUG
                        if ( Tblocks[Tblock_freelist_start].next < 0 )  {
                                mprintf(( "GrGlideTexture: AllocateTexture out of blocks!  Get John.\n" ));
                        }
                        #endif

                        //---- No room left, go back to start ---- 
                        ReleaseSlot(Tblock_usedlist_start);

                        nNewBlock = Tblock_usedlist_head = Tblock_usedlist_start; 
                        dwAddress = Tblock_min_address; 
                } else { 

                        //---- Make new block ---- 
                        nNewBlock = AllocBlock(); 
                } 

                next = Tblocks[Tblock_usedlist_head].next; 

                //---- Unlink blocks being overwritten ---- 
                while((next >= 0) && (dwAddress + size > Tblocks[next].start_address)) { 

                        int    nTemp = Tblocks[next].next; 

                        FreeBlock(next); 
                        next = nTemp; 
                } 

                //---- Init new block ---- 
                Tblocks[nNewBlock].next          = next; 
                Tblocks[nNewBlock].start_address = dwAddress; 
        } 

        Tblocks[nNewBlock].size = size; 
        Tblocks[nNewBlock].texture_ptr = texture_ptr;

        return Tblocks[nNewBlock].start_address; 
} 

void glide_tcache_set_initial_texture_mode()
{
        grTexMipMapMode( GR_TMU0, GR_MIPMAP_DISABLE, FXFALSE);
        grTexLodBiasValue( GR_TMU0, .5f);
        grTexClampMode( GR_TMU0, GR_TEXTURECLAMP_WRAP, GR_TEXTURECLAMP_WRAP);
        grTexFilterMode( GR_TMU0, GR_TEXTUREFILTER_BILINEAR, GR_TEXTUREFILTER_BILINEAR);
}

void glide_tcache_init()
{
        // if we're already inited, allocate nothing new)
        if(Textures == NULL){
                Textures = (tcache_slot *)malloc((MAX_TEXTURES)*sizeof(tcache_slot));
                if ( !Textures )        {
                        exit(1);        
                }
        }

        // AUX  
        /*
        Textures_aux = (tcache_slot*)malloc((MAX_TEXTURES) * MAX_BMAP_SECTIONS_X * MAX_BMAP_SECTIONS_Y sizeof(tcache_slot));
        if( !Textures_aux){
                exit(1);
        }
        */
        // if we're already inited, allocate nothing new)
        if(Texture_sections == NULL){
                Texture_sections = malloc(MAX_TEXTURES * MAX_BMAP_SECTIONS_X * MAX_BMAP_SECTIONS_Y * sizeof(tcache_slot));
                if(!Texture_sections){
                        exit(1);
                }
        }

        // if we're already inited, allocate nothing new)
        if(Glide_tmp_ram == NULL){
                Glide_tmp_ram = (ubyte *)malloc(256*256*2);
                if ( !Glide_tmp_ram )   {
                        exit(1);
                }
        }

        Glide_total_memory = guTexMemQueryAvail(GR_TMU0);
        Glide_start_address = grTexMinAddress(GR_TMU0);
        Glide_end_address = grTexMaxAddress(GR_TMU0);
        Glide_current_address = Glide_start_address;

        mprintf(( "Total texture memory on 3dfx card=%d bytes\n", Glide_total_memory ));

        glide_tcache_set_initial_texture_mode();
        
        InitBlocks(Glide_start_address,Glide_end_address, MAX_TEXTURES);

        // Init the texture structures  
        int i, idx, s_idx, count;
        count = 0;
        for( i=0; i<MAX_TEXTURES; i++ ) {
                Textures[i].bitmap_id = -1;             
                Textures[i].parent = NULL;
                
                for(idx=0; idx<MAX_BMAP_SECTIONS_X; idx++){
                        for(s_idx=0; s_idx<MAX_BMAP_SECTIONS_Y; s_idx++){
                                // AUX
                                // Textures[i].data_sections[idx][s_idx] = NULL;
                                // Textures[i].data_sections[idx][s_idx] = (tcache_slot*)malloc(sizeof(tcache_slot));
                                Textures[i].data_sections[idx][s_idx] = &((tcache_slot*)Texture_sections)[count++];
                                Textures[i].data_sections[idx][s_idx]->parent = &Textures[i];
                        }
                }               
        }
        
        // AUX
        /*
        for( i=0; i<MAX_AUX_TEXTURES; i++){
                Textures_aux[i].bitmap_id = -1;
                
                for(idx=0; idx<MAX_BMAP_SECTIONS_X; idx++){
                        for(s_idx=0; s_idx<MAX_BMAP_SECTIONS_Y; s_idx++){
                                Textures_aux[i].data_sections[idx][s_idx] = NULL;
                        }
                }
        }
        */

        Glide_textures_in = 0;
        Glide_last_bitmap_id = -1;
        Glide_last_section_x = -1;
        Glide_last_section_y = -1;

        Glide_last_detail = Detail.hardware_textures;
}

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

        // AUX
        /*
        if ( Textures_aux )     {
                free(Textures_aux);
                Textures_aux = NULL;
        }
        */
        if(Texture_sections){
                free(Texture_sections);
                Texture_sections = NULL;
        }

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

        ReleaseBlocks();
}

void glide_tcache_flush()
{
        if ( grSstIsBusy() )    {
                //mprintf(( "Pausing until 3DFX is idle before clearing texture RAM...\n" ));
                grSstIdle();    // Wait for idle
        }

        Glide_current_address = Glide_start_address;

        // Init the texture structures
        int i; //, idx, s_idx;
        for( i=0; i<MAX_TEXTURES; i++ ) {
                Textures[i].bitmap_id = -1;             

                // AUX
                /*
                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;
                        }
                }
                */
        }
        
        // AUX
        /*
        for( i=0; i<MAX_AUX_TEXTURES; i++){
                Textures_aux[i].bitmap_id = -1;
                
                for(idx=0; idx<MAX_BMAP_SECTIONS_X; idx++){
                        for(s_idx=0; s_idx<MAX_BMAP_SECTIONS_Y; s_idx++){
                                Textures_aux[i].data_sections[idx][s_idx] = NULL;
                        }
                }
        }
        */

        Glide_textures_in = 0;
        Glide_last_bitmap_id = -1;      
        Glide_last_section_x = -1;
        Glide_last_section_y = -1;


        Glide_explosion_vram = 0;

        FlushBlocks();
}

// get a free aux texture
// AUX
/*
int ga_reentrant = 0;
tcache_slot *glide_get_aux_slot()
{
        int idx;
        int index = -1;
        tcache_slot *ret;

        // never go in here more than twice
        if(ga_reentrant > 1){
                return NULL;
        }

        ga_reentrant++;

        for(idx=0; idx<MAX_AUX_TEXTURES; idx++){
                if(Textures_aux[idx].bitmap_id == -1){
                        index = idx;
                        break;
                }
        }

        // OH NO. This means we've run out of slots for bitmap sections. Let's just blast all of them free. whee!
        if(index == -1){
                mprintf(("AIEEEE! FLUSHIN SECTIONED BITMAPS!\n"));
                for(idx=0; idx<MAX_TEXTURES; idx++){
                        if((Textures[idx].bitmap_id > -1) && (Textures[idx].data_sections[0][0] != NULL)){
                                ReleaseSlot(&Textures[idx] - Textures);
                        }
                }
                        
                ret = glide_get_aux_slot();

                ga_reentrant--;
                return ret;
        }

        // hmm
        int s_idx;
        Textures_aux[index].bitmap_id = -1;     
        Textures_aux[index].data.vram_offset = 0;
        Textures_aux[index].data.vram_size = 0;
        for(idx=0; idx<MAX_BMAP_SECTIONS_X; idx++){
                for(s_idx=0; s_idx<MAX_BMAP_SECTIONS_Y; s_idx++){
                        Textures_aux[index].data_sections[idx][s_idx] = NULL;                   
                }
        }

        ret = &Textures_aux[index];
        ga_reentrant--;
        return ret;     
}
*/

void glide_tcache_frame()
{
        Glide_textures_in_frame = 0;
}

extern int palman_is_nondarkening(int r,int g, int b);

// 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
int glide_create_texture_sub(int bitmap_type, int bitmap_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 *tslot)
{       
        int i, j;       

        // sanity - make sure we're not going to run off the end of the bitmap
#ifndef NDEBUG
        SDL_assert(src_w <= (bmap_w - sx));
        SDL_assert(src_h <= (bmap_h - sy));
#endif

        if ( tex_w <= 16 ) tex_w = 16;
        else if ( tex_w <= 32 ) tex_w = 32;
        else if ( tex_w <= 64 ) tex_w = 64;
        else if ( tex_w <= 128 ) tex_w = 128;
        else {
                tex_w = 256;
        }

        if ( tex_h <= 16 ) tex_h = 16;
        else if ( tex_h <= 32 ) tex_h = 32;
        else if ( tex_h <= 64 ) tex_h = 64;
        else if ( tex_h <= 128 ) tex_h = 128;
        else {
                tex_h = 256;
        }       

        // these can never be shrunk. meaning, the texture _must_ be big enough to hold every pixel
        if ( (bitmap_type == TCACHE_TYPE_AABITMAP) || (bitmap_type == TCACHE_TYPE_BITMAP_SECTION) )     {
                // W & H must be within 8x of each other.       
                if ( (tex_w==16) && (tex_h==256) )      {
                        tex_w = 32;
                } else if ( (tex_w==256) && (tex_h==16) )       {
                        tex_h = 32;
                }
        } else {
                // W & H must be within 8x of each other.       
                if ( (tex_w==16) && (tex_h==256) )      {
                        tex_h = 128;
                } else if ( (tex_w==256) && (tex_h==16) )       {
                        tex_w = 128;
                }
        }

        ushort *bmp_data = data;
        ubyte *bmp_data_byte = (ubyte*)data;

        GrTextureFormat_t tex_format;

        if ( bitmap_type == TCACHE_TYPE_AABITMAP )      {
                tex_format = GR_TEXFMT_ALPHA_8;
                
                ubyte *lpSP;
                ubyte pix;
                ubyte xlat[256];
                
                for (i=0; i<16; i++ )   {
                        xlat[i] = ubyte(Gr_gamma_lookup[(i*255)/15]);
                }
                xlat[15] = xlat[1];
                pix = 255;
                for ( ; i<256; i++ )    {
                        xlat[i] = pix;
                }

                // upload to temp ram
                for (j = 0; j < tex_h; j++) {
                        // the proper line in the temp ram
                        lpSP = (ubyte*)(Glide_tmp_ram + tex_w * j);

                        // upload the line of texture from the source bitmap
                        for (i = 0; i < tex_w; i++) {
                                // if we're within the bounds of the section we're copying
                                if ( (j < src_h) && (i < src_w) )       {
                                        *lpSP++ = xlat[(ubyte)bmp_data_byte[(j * bmap_w) + i + sx]];
                                }
                                // otherwise just copy black
                                else {
                                        *lpSP++ = 0;
                                }
                        }
                }
        } else if(bitmap_type == TCACHE_TYPE_BITMAP_SECTION){
                tex_format = GR_TEXFMT_ARGB_1555;                               
                ushort *lpSP;                                           

                for (j = 0; j < src_h; j++) {
                        // the proper line in the temp ram
                        lpSP = (unsigned short*)(Glide_tmp_ram + tex_w * 2 * j);

                        // nice and clean
                        for (i = 0; i < src_w; i++) {                                                                                           
                                // stuff the texture into vram
                                *lpSP++ = bmp_data[((j+sy) * bmap_w) + sx + i];
                        }                       
                }
        } else {                
                tex_format = GR_TEXFMT_ARGB_1555;               
                fix u, utmp, v, du, dv;                         
                ushort *lpSP;           
                
                u = 0;

                // source line on the bitmap;           
                v = i2f(sy);

                // scale through the texture            
                du = (src_w * F1_0) / tex_w;
                dv = (src_h * F1_0) / tex_h;

                for (j = 0; j < tex_h; j++) {
                        // the proper line in the temp ram
                        lpSP = (unsigned short*)(Glide_tmp_ram + tex_w * 2 * j);

                        // pixel offset on this individual line of the source bitmap
                        utmp = u + i2f(sx);

                        // nice and clean
                        for (i = 0; i < tex_w; i++) {                                                                                           
                                // stuff the texture into vram
                                *lpSP++ = bmp_data[f2i(v) * bmap_w + f2i(utmp)];

                                // next pixel
                                utmp += du;                             
                        }

                        // next line in the source bitmap
                        v += dv;
                }
        }       

        GrLOD_t lod=GR_LOD_16;

        int longest = max(tex_w, tex_h);

        float uscale, vscale;           
        if ( bitmap_type == TCACHE_TYPE_AABITMAP )      {
                uscale = i2fl(bmap_w)*256.0f / i2fl(longest);
                vscale = i2fl(bmap_h)*256.0f / i2fl(longest);
        } else if(bitmap_type == TCACHE_TYPE_BITMAP_SECTION){
                uscale = i2fl(src_w)*256.0f / i2fl(longest);
                vscale = i2fl(src_h)*256.0f / i2fl(longest);
        } else {
                uscale = i2fl(tex_w)*256.0f / i2fl(longest);
                vscale = i2fl(tex_h)*256.0f / i2fl(longest);
        }

        switch( longest )       {
        case 16:                lod = GR_LOD_16; break;
        case 32:                lod = GR_LOD_32; break;
        case 64:                lod = GR_LOD_64; break;
        case 128:       lod = GR_LOD_128; break;
        case 256:       lod = GR_LOD_256; break;
        default:                Int3();
        }

        // GR_ASPECT_2x1        
        GrAspectRatio_t aspect = GR_ASPECT_1x1;         // aspect is widthxheight

        if ( tex_w < tex_h )    {
                int ratio = tex_h / tex_w;
                switch(ratio)   {
                case 1: aspect = GR_ASPECT_1x1; break;
                case 2: aspect = GR_ASPECT_1x2; break;
                case 4: aspect = GR_ASPECT_1x4; break;
                case 8: aspect = GR_ASPECT_1x8; break;
                default:        Int3();
                }
        } else {
                int ratio = tex_w / tex_h;
                switch(ratio)   {
                case 1: aspect = GR_ASPECT_1x1; break;
                case 2: aspect = GR_ASPECT_2x1; break;
                case 4: aspect = GR_ASPECT_4x1; break;
                case 8: aspect = GR_ASPECT_8x1; break;
                default:        Int3();
                }
        }


        GrTexInfo info;

        info.smallLod = lod;                                    //GR_LOD_256;
        info.largeLod = lod;                                    //GR_LOD_256;
        info.aspectRatio = aspect;                      //GR_ASPECT_1x1;
        info.format = tex_format;                               //GR_TEXFMT_ARGB_1555;
        info.data = Glide_tmp_ram;                                              //source data

        int bytes_needed = grTexTextureMemRequired( GR_MIPMAPLEVELMASK_BOTH, &info );

        // if   ( (tslot->data.vram_offset == 0) || ((tslot->data.vram_offset>0)&&(bytes_needed>tslot->data.vram_size)))        {
                tslot->data.vram_offset = AllocateTexture( bytes_needed, tslot );
                tslot->data.vram_size = bytes_needed;
                Glide_textures_in += bytes_needed;
        // }

        tslot->data.format = tex_format;
        tslot->data.lod = lod;
        tslot->data.aspect = aspect;
        tslot->bitmap_id = bitmap_handle;
        tslot->uscale = uscale;
        tslot->vscale = vscale; 
        
        grTexDownloadMipMap(GR_TMU0, tslot->data.vram_offset, GR_MIPMAPLEVELMASK_BOTH, &info); 
        Glide_textures_in_frame += bytes_needed;        

        return 1;
}

int glide_create_texture( int bitmap_handle, int bitmap_type, tcache_slot *tslot )
{
        int ret;
        ubyte flags;
        bitmap *bmp;
        ubyte bpp = 16;

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

        if ( bitmap_type != TCACHE_TYPE_AABITMAP )      {
                // Detail.debris_culling goes from 0 to 4.
                max_w /= 16>>Detail.hardware_textures;
                max_h /= 16>>Detail.hardware_textures;
        }       

        // call the helper
        ret = glide_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);      

        // unlock the bitmap
        bm_unlock(bitmap_handle);

        // return
        return ret;
}

// create a sectioned texture
int glide_create_texture_sectioned(int bitmap_handle, int bitmap_type, tcache_slot *tslot, int sx, int sy)
{
        int ret;
        ubyte flags;
        bitmap *bmp;
        int section_x, section_y;

        // setup texture/bitmap flags
        SDL_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);     

        // call the helper
        ret = glide_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);  

        // unlock the bitmap
        bm_unlock(bitmap_handle);

        // return
        return ret;
}


DCF(exp_flush, "")
{
        Glide_explosion_vram = 0;
}

extern int bm_get_cache_slot( int bitmap_id, int separate_ani_frames );

// Returns FALSE if error
int glide_tcache_set( int bitmap_id, int bitmap_type, float *u_ratio, float *v_ratio, int fail_on_full, int sx, int sy, int force )
{               
        bitmap *bmp;
        int idx, s_idx;

        if ( Glide_last_detail != Detail.hardware_textures )    {
                Glide_last_detail = Detail.hardware_textures;
                glide_tcache_flush();
        }

        // Check if this is the same as the last one... if so, we don't need to
        // do anything.
        if ( (Glide_last_bitmap_id == bitmap_id) && (Glide_last_bitmap_type==bitmap_type) && (Glide_last_section_x == sx) && (Glide_last_section_y == sy) && !force)    {
                *u_ratio = Glide_last_u_ratio;
                *v_ratio = Glide_last_v_ratio;
                return 1;
        }

        int n;
        n = bm_get_cache_slot( bitmap_id, 1 );

        tcache_slot * t = &Textures[n];

        // if this is a sectioned bitmap
        if(bitmap_type == TCACHE_TYPE_BITMAP_SECTION){          
                // if the texture sections haven't been created yet
                if((t->bitmap_id < 0) || (t->bitmap_id != bitmap_id) || force){

                        if(t->bitmap_id < 0){
                                t->data.vram_offset = 0;
                        }                       

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

                        // first we need to get enough free aux textures                        
                        // AUX
                        /*
                        for(idx=0; idx<bmp->sections.num_x; idx++){                             
                                for(s_idx=0; s_idx<bmp->sections.num_y; s_idx++){
                                        // try and get a feww slot
                                        t->data_sections[idx][s_idx] = glide_get_aux_slot();
                                        if(t->data_sections[idx][s_idx] == NULL){
                                                Int3();
                                                return 0;
                                        }                               
                                        t->data_sections[idx][s_idx]->bitmap_id = 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++){                                                                               
                                        if(t->bitmap_id < 0){
                                                t->data_sections[idx][s_idx]->data.vram_offset = 0;
                                        }

                                        t->data_sections[idx][s_idx]->bitmap_id = bitmap_id;
                                        glide_create_texture_sectioned( bitmap_id, bitmap_type, t->data_sections[idx][s_idx], idx, s_idx);
                                }
                        }

                        t->bitmap_id = bitmap_id;
                }

                // swap in the texture we want                          
                t = t->data_sections[sx][sy];
        }
        // all other "normal" textures
        else {
                // no texture yet
                if ( t->bitmap_id < 0) {
                        t->data.vram_offset = 0;                
                        glide_create_texture( bitmap_id, bitmap_type, t );
                }
                // different bitmap altogether
                else if ( (t->bitmap_id != bitmap_id) || force) {
                        glide_create_texture( bitmap_id, bitmap_type, t );
                }
        }               

        *u_ratio = t->uscale;
        *v_ratio = t->vscale;

        GrTexInfo info;

        info.smallLod = t->data.lod;                            //GR_LOD_256;
        info.largeLod = t->data.lod;                            //GR_LOD_256;
        info.aspectRatio = t->data.aspect;              //GR_ASPECT_1x1;
        info.format = t->data.format;                           //GR_TEXFMT_ARGB_1555;
        info.data = 0;                                                                  //source data

        grTexSource( GR_TMU0, t->data.vram_offset, GR_MIPMAPLEVELMASK_BOTH, &info );

        // Save current state so we don't have to do anything time consuming next time
        // we set this exact same texture
        Glide_last_bitmap_id = bitmap_id;
        Glide_last_bitmap_type = bitmap_type;
        Glide_last_section_x = sx;
        Glide_last_section_y = sy;
        Glide_last_u_ratio = t->uscale;
        Glide_last_v_ratio = t->vscale;

        return 1;
}