src/graphics/grgl1.cpp

   1 /*
   2  * Copyright (C) Volition, Inc. 1999.  All rights reserved.
   3  *
   4  * All source code herein is the property of Volition, Inc. You may not sell
   5  * or otherwise commercially exploit the source or things you created based on
   6  * the source.
   7  */
   8
   9 #include "gropengl.h"
  10 #include "grgl1.h"
  11 #include "gropenglinternal.h"
  12 #include "2d.h"
  13 #include "mouse.h"
  14 #include "pstypes.h"
  15 #include "cfile.h"
  16 #include "bmpman.h"
  17 #include "grinternal.h"
  18
  19
  20 int OGL_fog_mode = 0;
  21
  22 int GL_one_inited = 0;
  23
  24
  25 volatile int GL_activate = 0;
  26 volatile int GL_deactivate = 0;
  27
  28 static GLuint Gr_saved_screen_tex = 0;
  29
  30 static int Gr_opengl_mouse_saved = 0;
  31 static int Gr_opengl_mouse_saved_x = 0;
  32 static int Gr_opengl_mouse_saved_y = 0;
  33 static int Gr_opengl_mouse_saved_w = 0;
  34 static int Gr_opengl_mouse_saved_h = 0;
  35 static ubyte *Gr_opengl_mouse_saved_data = NULL;
  36
  37
  38 PFNGLSECONDARYCOLORPOINTERPROC vglSecondaryColorPointer = NULL;
  39
  40
  41 static gr_alpha_blend GL_current_alpha_blend = (gr_alpha_blend) -1;
  42 static gr_zbuffer_type GL_current_zbuffer_type = (gr_zbuffer_type) -1;
  43
  44 void opengl1_set_state(gr_texture_source ts, gr_alpha_blend ab, gr_zbuffer_type zt)
  45 {
  46         opengl1_set_texture_state(ts);
  47
  48         if (ab != GL_current_alpha_blend) {
  49                 switch (ab) {
  50                         case ALPHA_BLEND_NONE:                  // 1*SrcPixel + 0*DestPixel
  51                                 glBlendFunc(GL_ONE, GL_ZERO);
  52                                 break;
  53                         case ALPHA_BLEND_ADDITIVE:              // 1*SrcPixel + 1*DestPixel
  54                                 glBlendFunc(GL_ONE, GL_ONE);
  55                                 break;
  56                         case ALPHA_BLEND_ALPHA_ADDITIVE:        // Alpha*SrcPixel + 1*DestPixel
  57                                 glBlendFunc(GL_SRC_ALPHA, GL_ONE);
  58                                 break;
  59                         case ALPHA_BLEND_ALPHA_BLEND_ALPHA:     // Alpha*SrcPixel + (1-Alpha)*DestPixel
  60                                 glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
  61                                 break;
  62                         case ALPHA_BLEND_ALPHA_BLEND_SRC_COLOR: // Alpha*SrcPixel + (1-SrcPixel)*DestPixel
  63                                 glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_COLOR);
  64                                 break;
  65                         default:
  66                                 break;
  67                 }
  68
  69                 GL_current_alpha_blend = ab;
  70         }
  71
  72         if (zt != GL_current_zbuffer_type) {
  73                 switch (zt) {
  74                         case ZBUFFER_TYPE_NONE:
  75                                 glDepthFunc(GL_ALWAYS);
  76                                 glDepthMask(GL_FALSE);
  77                                 break;
  78                         case ZBUFFER_TYPE_READ:
  79                                 glDepthFunc(GL_LESS);
  80                                 glDepthMask(GL_FALSE);
  81                                 break;
  82                         case ZBUFFER_TYPE_WRITE:
  83                                 glDepthFunc(GL_ALWAYS);
  84                                 glDepthMask(GL_TRUE);
  85                                 break;
  86                         case ZBUFFER_TYPE_FULL:
  87                                 glDepthFunc(GL_LESS);
  88                                 glDepthMask(GL_TRUE);
  89                                 break;
  90                         default:
  91                                 break;
  92                 }
  93
  94                 GL_current_zbuffer_type = zt;
  95         }
  96 }
  97
  98 void opengl1_cleanup()
  99 {
 100         if ( !GL_one_inited ) {
 101                 return;
 102         }
 103
 104         gr_opengl1_reset_clip();
 105         gr_opengl1_clear();
 106         gr_opengl1_flip();
 107
 108         opengl1_tcache_cleanup();
 109
 110         GL_one_inited = 0;
 111 }
 112
 113 static void opengl1_init_func_pointers()
 114 {
 115         gr_screen.gf_flip = gr_opengl1_flip;
 116         gr_screen.gf_set_clip = gr_opengl1_set_clip;
 117         gr_screen.gf_reset_clip = gr_opengl1_reset_clip;
 118
 119         gr_screen.gf_clear = gr_opengl1_clear;
 120
 121         gr_screen.gf_aabitmap = gr_opengl1_aabitmap;
 122         gr_screen.gf_aabitmap_ex = gr_opengl1_aabitmap_ex;
 123
 124         gr_screen.gf_rect = gr_opengl1_rect;
 125         gr_screen.gf_shade = gr_opengl1_shade;
 126         gr_screen.gf_string = gr_opengl1_string;
 127         gr_screen.gf_circle = gr_opengl1_circle;
 128
 129         gr_screen.gf_line = gr_opengl1_line;
 130         gr_screen.gf_aaline = gr_opengl1_aaline;
 131         gr_screen.gf_pixel = gr_opengl1_pixel;
 132         gr_screen.gf_scaler = gr_opengl1_scaler;
 133         gr_screen.gf_tmapper = gr_opengl1_tmapper;
 134
 135         gr_screen.gf_gradient = gr_opengl1_gradient;
 136
 137         gr_screen.gf_print_screen = gr_opengl1_print_screen;
 138
 139         gr_screen.gf_fade_in = gr_opengl1_fade_in;
 140         gr_screen.gf_fade_out = gr_opengl1_fade_out;
 141         gr_screen.gf_flash = gr_opengl1_flash;
 142
 143         gr_screen.gf_zbuffer_clear = gr_opengl1_zbuffer_clear;
 144
 145         gr_screen.gf_save_screen = gr_opengl1_save_screen;
 146         gr_screen.gf_restore_screen = gr_opengl1_restore_screen;
 147         gr_screen.gf_free_screen = gr_opengl1_free_screen;
 148
 149         gr_screen.gf_dump_frame_start = gr_opengl1_dump_frame_start;
 150         gr_screen.gf_dump_frame_stop = gr_opengl1_dump_frame_stop;
 151         gr_screen.gf_dump_frame = gr_opengl1_dump_frame;
 152
 153         gr_screen.gf_set_gamma = gr_opengl1_set_gamma;
 154
 155         gr_screen.gf_lock = gr_opengl1_lock;
 156         gr_screen.gf_unlock = gr_opengl1_unlock;
 157
 158         gr_screen.gf_fog_set = gr_opengl1_fog_set;
 159
 160         gr_screen.gf_get_region = gr_opengl1_get_region;
 161
 162         gr_screen.gf_set_cull = gr_opengl1_set_cull;
 163
 164         gr_screen.gf_cross_fade = gr_opengl1_cross_fade;
 165
 166         gr_screen.gf_preload_init = gr_opengl1_preload_init;
 167         gr_screen.gf_preload = gr_opengl1_preload;
 168
 169         gr_screen.gf_zbias = gr_opengl1_zbias;
 170
 171         gr_screen.gf_force_windowed = gr_opengl_force_windowed;
 172         gr_screen.gf_force_fullscreen = gr_opengl_force_fullscreen;
 173         gr_screen.gf_toggle_fullscreen = gr_opengl_toggle_fullscreen;
 174
 175         gr_screen.gf_set_viewport = gr_opengl1_set_viewport;
 176
 177         gr_screen.gf_activate = gr_opengl1_activate;
 178
 179         gr_screen.gf_release_texture = gr_opengl1_release_texture;
 180 }
 181
 182 void opengl1_init()
 183 {
 184         if (GL_one_inited) {
 185                 return;
 186         }
 187
 188         /*
 189           1 = use secondary color ext
 190           2 = use opengl linear fog
 191          */
 192         OGL_fog_mode = 2;
 193
 194         // only available with OpenGL 1.2+, must get ptr for Windows
 195         vglSecondaryColorPointer = (PFNGLSECONDARYCOLORPOINTERPROC)SDL_GL_GetProcAddress("glSecondaryColorPointer");
 196
 197         if (vglSecondaryColorPointer) {
 198                 OGL_fog_mode = 1;
 199         }
 200
 201         mprintf(("  Fog mode: %s\n", (OGL_fog_mode == 1) ? "secondary color" : "linear"));
 202
 203         glShadeModel(GL_SMOOTH);
 204         glEnable(GL_DITHER);
 205         glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
 206         glHint(GL_FOG_HINT, GL_NICEST);
 207
 208         glEnable(GL_DEPTH_TEST);
 209         glEnable(GL_BLEND);
 210
 211         glEnable(GL_TEXTURE_2D);
 212
 213         glDepthRange(0.0, 1.0);
 214
 215         glPixelStorei(GL_PACK_ALIGNMENT, 1);
 216         glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 217
 218         glFlush();
 219
 220         opengl1_init_func_pointers();
 221         opengl1_tcache_init();
 222
 223         gr_opengl1_clear();
 224
 225         GL_one_inited = 1;
 226 }
 227
 228 void gr_opengl1_activate(int active)
 229 {
 230         if (active) {
 231                 GL_activate++;
 232
 233                 // don't grab key/mouse if cmdline says so or if we're fullscreen
 234         //      if(!Cmdline_no_grab && !(SDL_GetVideoSurface()->flags & SDL_FULLSCREEN)) {
 235         //              SDL_WM_GrabInput(SDL_GRAB_ON);
 236         //      }
 237         } else {
 238                 GL_deactivate++;
 239
 240                 // let go of mouse/keyboard
 241         //      SDL_WM_GrabInput(SDL_GRAB_OFF);
 242         }
 243 }
 244
 245 void gr_opengl1_clear()
 246 {
 247         glClearColor(gr_screen.current_clear_color.red / 255.0f,
 248                 gr_screen.current_clear_color.green / 255.0f,
 249                 gr_screen.current_clear_color.blue / 255.0f, 1.0f);
 250
 251         glClear( GL_COLOR_BUFFER_BIT );
 252 }
 253
 254 void gr_opengl1_flip()
 255 {
 256         if ( !GL_one_inited ) {
 257                 return;
 258         }
 259
 260         gr_reset_clip();
 261
 262         mouse_eval_deltas();
 263
 264         Gr_opengl_mouse_saved = 0;
 265
 266         if ( mouse_is_visible() )       {
 267                 int mx, my;
 268
 269                 gr_reset_clip();
 270                 mouse_get_pos( &mx, &my );
 271
 272                 gr_opengl1_save_mouse_area(mx,my,32,32);
 273
 274                 if (Gr_cursor == -1) {
 275 #ifndef NDEBUG
 276                         gr_set_color(255,255,255);
 277                         gr_line(mx, my, mx+7, my + 7);
 278                         gr_line(mx, my, mx+5, my );
 279                         gr_line(mx, my, mx, my+5);
 280 #endif
 281                 } else {
 282                         gr_set_bitmap(Gr_cursor);
 283                         gr_bitmap(mx, my);
 284                 }
 285          }
 286
 287 #ifndef NDEBUG
 288         GLenum error = GL_NO_ERROR;
 289
 290         do {
 291                 error = glGetError();
 292
 293                 if (error != GL_NO_ERROR) {
 294                         nprintf(("Warning", "!!DEBUG!! OpenGL Error: %d\n", error));
 295                 }
 296         } while (error != GL_NO_ERROR);
 297 #endif
 298
 299         SDL_GL_SwapWindow(GL_window);
 300
 301         opengl1_tcache_frame();
 302
 303         int cnt = GL_activate;
 304         if ( cnt )      {
 305                 GL_activate-=cnt;
 306                 opengl1_tcache_flush();
 307                 // gr_opengl_clip_cursor(1); /* mouse grab, see opengl_activate */
 308         }
 309
 310         cnt = GL_deactivate;
 311         if ( cnt )      {
 312                 GL_deactivate-=cnt;
 313                 // gr_opengl_clip_cursor(0);  /* mouse grab, see opengl_activate */
 314         }
 315 }
 316
 317 void gr_opengl1_set_clip(int x,int y,int w,int h)
 318 {
 319         // check for sanity of parameters
 320         if (x < 0)
 321                 x = 0;
 322         if (y < 0)
 323                 y = 0;
 324
 325         if (x >= gr_screen.max_w)
 326                 x = gr_screen.max_w - 1;
 327         if (y >= gr_screen.max_h)
 328                 y = gr_screen.max_h - 1;
 329
 330         if (x + w > gr_screen.max_w)
 331                 w = gr_screen.max_w - x;
 332         if (y + h > gr_screen.max_h)
 333                 h = gr_screen.max_h - y;
 334
 335         if (w > gr_screen.max_w)
 336                 w = gr_screen.max_w;
 337         if (h > gr_screen.max_h)
 338                 h = gr_screen.max_h;
 339
 340         gr_screen.offset_x = x;
 341         gr_screen.offset_y = y;
 342         gr_screen.clip_left = 0;
 343         gr_screen.clip_right = w-1;
 344         gr_screen.clip_top = 0;
 345         gr_screen.clip_bottom = h-1;
 346         gr_screen.clip_width = w;
 347         gr_screen.clip_height = h;
 348
 349         x = fl2i((x * GL_viewport_scale_w) + 0.5f) + GL_viewport_x;
 350         y = fl2i((y * GL_viewport_scale_h) + 0.5f) + GL_viewport_y;
 351         w = fl2i((w * GL_viewport_scale_w) + 0.5f);
 352         h = fl2i((h * GL_viewport_scale_h) + 0.5f);
 353
 354         glEnable(GL_SCISSOR_TEST);
 355         glScissor(x, GL_viewport_h-y-h, w, h);
 356 }
 357
 358 void gr_opengl1_reset_clip()
 359 {
 360         gr_screen.offset_x = 0;
 361         gr_screen.offset_y = 0;
 362         gr_screen.clip_left = 0;
 363         gr_screen.clip_top = 0;
 364         gr_screen.clip_right = gr_screen.max_w - 1;
 365         gr_screen.clip_bottom = gr_screen.max_h - 1;
 366         gr_screen.clip_width = gr_screen.max_w;
 367         gr_screen.clip_height = gr_screen.max_h;
 368
 369         glDisable(GL_SCISSOR_TEST);
 370 }
 371
 372 void gr_opengl1_print_screen(const char *filename)
 373 {
 374         char tmp[MAX_FILENAME_LEN];
 375         ubyte *buf = NULL;
 376
 377         SDL_strlcpy( tmp, filename, sizeof(tmp) );
 378         SDL_strlcat( tmp, NOX(".tga"), sizeof(tmp) );
 379
 380         buf = (ubyte*)malloc(GL_viewport_w * GL_viewport_h * 3);
 381
 382         if (buf == NULL) {
 383                 return;
 384         }
 385
 386         CFILE *f = cfopen(tmp, "wb", CFILE_NORMAL, CF_TYPE_ROOT);
 387
 388         if (f == NULL) {
 389                 free(buf);
 390                 return;
 391         }
 392
 393         // Write the TGA header
 394         cfwrite_ubyte( 0, f );  //      IDLength;
 395         cfwrite_ubyte( 0, f );  //      ColorMapType;
 396         cfwrite_ubyte( 2, f );  //      ImageType;              // 2 = 24bpp, uncompressed, 10=24bpp rle compressed
 397         cfwrite_ushort( 0, f ); // CMapStart;
 398         cfwrite_ushort( 0, f ); //      CMapLength;
 399         cfwrite_ubyte( 0, f );  // CMapDepth;
 400         cfwrite_ushort( 0, f ); //      XOffset;
 401         cfwrite_ushort( 0, f ); //      YOffset;
 402         cfwrite_ushort( (ushort)GL_viewport_w, f );     //      Width;
 403         cfwrite_ushort( (ushort)GL_viewport_h, f );     //      Height;
 404         cfwrite_ubyte( 24, f ); //PixelDepth;
 405         cfwrite_ubyte( 0, f );  //ImageDesc;
 406
 407         memset(buf, 0, GL_viewport_w * GL_viewport_h * 3);
 408
 409         glReadPixels(GL_viewport_x, GL_viewport_y, GL_viewport_w, GL_viewport_h, GL_BGR, GL_UNSIGNED_BYTE, buf);
 410
 411         cfwrite(buf, GL_viewport_w * GL_viewport_h * 3, 1, f);
 412
 413         cfclose(f);
 414
 415         free(buf);
 416 }
 417
 418 void gr_opengl1_fog_set(int fog_mode, int r, int g, int b, float fog_near, float fog_far)
 419 {
 420         SDL_assert((r >= 0) && (r < 256));
 421         SDL_assert((g >= 0) && (g < 256));
 422         SDL_assert((b >= 0) && (b < 256));
 423
 424         if (fog_mode == GR_FOGMODE_NONE) {
 425                 if (gr_screen.current_fog_mode != fog_mode) {
 426                         glDisable(GL_FOG);
 427
 428                         if (OGL_fog_mode == 1) {
 429                                 glDisable(GL_COLOR_SUM);
 430                         }
 431                 }
 432
 433                 gr_screen.current_fog_mode = fog_mode;
 434
 435                 return;
 436         }
 437
 438         if (gr_screen.current_fog_mode != fog_mode) {
 439                 glEnable(GL_FOG);
 440
 441                 if (OGL_fog_mode == 1) {
 442                         glEnable(GL_COLOR_SUM);
 443                 } else if (OGL_fog_mode == 2) {
 444                         glFogi(GL_FOG_MODE, GL_LINEAR);
 445                 }
 446
 447                 gr_screen.current_fog_mode = fog_mode;
 448         }
 449
 450         if ( (gr_screen.current_fog_color.red != r) ||
 451                         (gr_screen.current_fog_color.green != g) ||
 452                         (gr_screen.current_fog_color.blue != b) ) {
 453                 GLfloat fc[4];
 454
 455                 gr_init_color( &gr_screen.current_fog_color, r, g, b );
 456
 457                 fc[0] = r / 255.0f;
 458                 fc[1] = g / 255.0f;
 459                 fc[2] = b / 255.0f;
 460                 fc[3] = 1.0f;
 461
 462                 glFogfv(GL_FOG_COLOR, fc);
 463         }
 464
 465         if( (fog_near >= 0.0f) && (fog_far >= 0.0f) &&
 466                         ((fog_near != gr_screen.fog_near) ||
 467                         (fog_far != gr_screen.fog_far)) ) {
 468                 gr_screen.fog_near = fog_near;
 469                 gr_screen.fog_far = fog_far;
 470
 471                 if (OGL_fog_mode == 2) {
 472                         glFogf(GL_FOG_START, fog_near);
 473                         glFogf(GL_FOG_END, fog_far);
 474                 }
 475         }
 476 }
 477
 478 void gr_opengl1_set_cull(int cull)
 479 {
 480         if (cull) {
 481                 glEnable (GL_CULL_FACE);
 482                 glFrontFace (GL_CCW);
 483         } else {
 484                 glDisable (GL_CULL_FACE);
 485         }
 486 }
 487
 488 void gr_opengl1_zbuffer_clear(int mode)
 489 {
 490         if (mode) {
 491                 Gr_zbuffering = 1;
 492                 Gr_zbuffering_mode = GR_ZBUFF_FULL;
 493                 Gr_global_zbuffering = 1;
 494
 495                 opengl1_set_state( TEXTURE_SOURCE_NONE, ALPHA_BLEND_NONE, ZBUFFER_TYPE_FULL );
 496                 glClear ( GL_DEPTH_BUFFER_BIT );
 497         } else {
 498                 Gr_zbuffering = 0;
 499                 Gr_zbuffering_mode = GR_ZBUFF_NONE;
 500                 Gr_global_zbuffering = 0;
 501         }
 502 }
 503
 504 void gr_opengl1_fade_in(int instantaneous)
 505 {
 506         // Empty - DDOI
 507 }
 508
 509 void gr_opengl1_fade_out(int instantaneous)
 510 {
 511         // Empty - DDOI
 512 }
 513
 514 void gr_opengl1_get_region(int front, int w, int h, ubyte *data)
 515 {
 516         if (front) {
 517                 glReadBuffer(GL_FRONT);
 518         } else {
 519                 glReadBuffer(GL_BACK);
 520         }
 521
 522         opengl1_set_state(TEXTURE_SOURCE_NO_FILTERING, ALPHA_BLEND_NONE, ZBUFFER_TYPE_NONE);
 523
 524         glPixelStorei(GL_UNPACK_ROW_LENGTH, GL_viewport_w);
 525
 526         int x = GL_viewport_x;
 527         int y = (GL_viewport_y+GL_viewport_h)-h-1;
 528
 529         GLenum pxtype = GL_UNSIGNED_SHORT_1_5_5_5_REV;
 530
 531         if (gr_screen.bytes_per_pixel == 4) {
 532                 pxtype = GL_UNSIGNED_BYTE;
 533         }
 534
 535         glReadPixels(x, y, w, h, GL_BGRA, pxtype, data);
 536
 537         glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
 538 }
 539
 540 void gr_opengl1_save_mouse_area(int x, int y, int w, int h)
 541 {
 542         int x1, y1, x2, y2;
 543
 544         w = fl2i((w * GL_viewport_scale_w) + 0.5f);
 545         h = fl2i((h * GL_viewport_scale_h) + 0.5f);
 546
 547         x1 = x;
 548         y1 = y;
 549         x2 = x+w-1;
 550         y2 = y+h-1;
 551
 552         CAP(x1, 0, GL_viewport_w);
 553         CAP(x2, 0, GL_viewport_w);
 554         CAP(y1, 0, GL_viewport_h);
 555         CAP(y2, 0, GL_viewport_h);
 556
 557         Gr_opengl_mouse_saved_x = x1;
 558         Gr_opengl_mouse_saved_y = y1;
 559         Gr_opengl_mouse_saved_w = x2 - x1 + 1;
 560         Gr_opengl_mouse_saved_h = y2 - y1 + 1;
 561
 562         if ( (Gr_opengl_mouse_saved_w < 1) || (Gr_opengl_mouse_saved_h < 1) ) {
 563                 return;
 564         }
 565
 566         if (Gr_opengl_mouse_saved_data == NULL) {
 567                 Gr_opengl_mouse_saved_data = (ubyte*)malloc(w * h * gr_screen.bytes_per_pixel);
 568
 569                 if ( !Gr_opengl_mouse_saved_data ) {
 570                         return;
 571                 }
 572         }
 573
 574         opengl1_set_state(TEXTURE_SOURCE_NO_FILTERING, ALPHA_BLEND_NONE, ZBUFFER_TYPE_NONE);
 575
 576         x1 = GL_viewport_x+Gr_opengl_mouse_saved_x;
 577         y1 = (GL_viewport_y+GL_viewport_h)-Gr_opengl_mouse_saved_y-Gr_opengl_mouse_saved_h;
 578
 579         GLenum pxtype = GL_UNSIGNED_SHORT_1_5_5_5_REV;
 580
 581         if (gr_screen.bytes_per_pixel == 4) {
 582                 pxtype = GL_UNSIGNED_BYTE;
 583         }
 584
 585         glReadBuffer(GL_BACK);
 586         glReadPixels(x1, y1, Gr_opengl_mouse_saved_w, Gr_opengl_mouse_saved_h,
 587                         GL_BGRA, pxtype, Gr_opengl_mouse_saved_data);
 588
 589         Gr_opengl_mouse_saved = 1;
 590 }
 591
 592 int gr_opengl1_save_screen()
 593 {
 594         gr_reset_clip();
 595
 596         if (Gr_saved_screen_tex) {
 597                 mprintf(( "Screen already saved!\n" ));
 598                 return -1;
 599         }
 600
 601         glGenTextures(1, &Gr_saved_screen_tex);
 602
 603         if ( !Gr_saved_screen_tex ) {
 604                 mprintf(( "Couldn't create texture for saved screen!\n" ));
 605                 return -1;
 606         }
 607
 608         opengl1_set_state(TEXTURE_SOURCE_NO_FILTERING, ALPHA_BLEND_NONE, ZBUFFER_TYPE_NONE);
 609
 610         glBindTexture(GL_TEXTURE_2D, Gr_saved_screen_tex);
 611
 612         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 613         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 614         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
 615         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
 616         glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
 617
 618         glReadBuffer(GL_FRONT);
 619         glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, GL_viewport_x, GL_viewport_y,
 620                         GL_viewport_w, GL_viewport_h, 0);
 621
 622         if (Gr_opengl_mouse_saved) {
 623                 int x = Gr_opengl_mouse_saved_x;
 624                 int y = GL_viewport_h-Gr_opengl_mouse_saved_y-Gr_opengl_mouse_saved_h;
 625
 626                 GLenum pxtype = GL_UNSIGNED_SHORT_1_5_5_5_REV;
 627
 628                 if (gr_screen.bytes_per_pixel == 4) {
 629                         pxtype = GL_UNSIGNED_BYTE;
 630                 }
 631
 632                 glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, Gr_opengl_mouse_saved_w,
 633                                 Gr_opengl_mouse_saved_h, GL_BGRA, pxtype,
 634                                 Gr_opengl_mouse_saved_data);
 635         }
 636
 637         glBindTexture(GL_TEXTURE_2D, 0);
 638
 639         return 0;
 640 }
 641
 642 void gr_opengl1_restore_screen(int id)
 643 {
 644         gr_reset_clip();
 645
 646         if ( !Gr_saved_screen_tex ) {
 647                 gr_clear();
 648                 return;
 649         }
 650
 651         glBindTexture(GL_TEXTURE_2D, Gr_saved_screen_tex);
 652
 653         if (Gr_opengl_mouse_saved) {
 654                 int x = Gr_opengl_mouse_saved_x;
 655                 int y = GL_viewport_h-Gr_opengl_mouse_saved_y-Gr_opengl_mouse_saved_h;
 656
 657                 GLenum pxtype = GL_UNSIGNED_SHORT_1_5_5_5_REV;
 658
 659                 if (gr_screen.bytes_per_pixel == 4) {
 660                         pxtype = GL_UNSIGNED_BYTE;
 661                 }
 662
 663                 glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, Gr_opengl_mouse_saved_w,
 664                                 Gr_opengl_mouse_saved_h, GL_BGRA, pxtype,
 665                                 Gr_opengl_mouse_saved_data);
 666         }
 667
 668         glMatrixMode(GL_MODELVIEW);
 669         glPushMatrix();
 670         glLoadIdentity();
 671         glScalef(1.0f, -1.0f, 1.0f);
 672
 673         int tex_coord[] = { 0, 0, 0, 1, 1, 0, 1, 1 };
 674         int ver_coord[] = { GL_viewport_x, GL_viewport_y, GL_viewport_x,
 675                         GL_viewport_h, GL_viewport_w, GL_viewport_y, GL_viewport_w,
 676                         GL_viewport_h
 677         };
 678
 679         glEnableClientState(GL_TEXTURE_COORD_ARRAY);
 680         glEnableClientState(GL_VERTEX_ARRAY);
 681
 682         glTexCoordPointer(2, GL_INT, 0, &tex_coord);
 683         glVertexPointer(2, GL_INT, 0, &ver_coord);
 684
 685         glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
 686
 687         glDisableClientState(GL_TEXTURE_COORD_ARRAY);
 688         glDisableClientState(GL_VERTEX_ARRAY);
 689
 690         glPopMatrix();
 691
 692         glBindTexture(GL_TEXTURE_2D, 0);
 693 }
 694
 695 void gr_opengl1_free_screen(int id)
 696 {
 697         if (Gr_saved_screen_tex) {
 698                 glDeleteTextures(1, &Gr_saved_screen_tex);
 699                 Gr_saved_screen_tex = 0;
 700         }
 701 }
 702
 703 void gr_opengl1_dump_frame_start(int first_frame, int frames_between_dumps)
 704 {
 705         STUB_FUNCTION;
 706 }
 707
 708 void gr_opengl1_dump_frame_stop()
 709 {
 710         STUB_FUNCTION;
 711 }
 712
 713 void gr_opengl1_dump_frame()
 714 {
 715         STUB_FUNCTION;
 716 }
 717
 718 uint gr_opengl1_lock()
 719 {
 720         return 1;
 721 }
 722
 723 void gr_opengl1_unlock()
 724 {
 725 }
 726
 727 void gr_opengl1_zbias(int bias)
 728 {
 729         if (bias) {
 730                 glEnable(GL_POLYGON_OFFSET_FILL);
 731                 glPolygonOffset(0.0f, GLfloat(-bias));
 732         } else {
 733                 glDisable(GL_POLYGON_OFFSET_FILL);
 734         }
 735 }
 736
 737 void gr_opengl1_set_viewport(int width, int height)
 738 {
 739         int w, h, x, y;
 740
 741         float ratio = gr_screen.max_w / i2fl(gr_screen.max_h);
 742
 743         w = width;
 744         h = fl2i((width / ratio) + 0.5f);
 745
 746         if (h > height) {
 747                 h = height;
 748                 w = fl2i((height * ratio) + 0.5f);
 749         }
 750
 751         x = (width - w) / 2;
 752         y = (height - h) / 2;
 753
 754         GL_viewport_x = x;
 755         GL_viewport_y = y;
 756         GL_viewport_w = w;
 757         GL_viewport_h = h;
 758         GL_viewport_scale_w = w / i2fl(gr_screen.max_w);
 759         GL_viewport_scale_h = h / i2fl(gr_screen.max_h);
 760
 761         glViewport(GL_viewport_x, GL_viewport_y, GL_viewport_w, GL_viewport_h);
 762
 763         glMatrixMode(GL_PROJECTION);
 764         glLoadIdentity();
 765         glOrtho(0, GL_viewport_w, GL_viewport_h, 0, 0.0, 1.0);
 766         glMatrixMode(GL_MODELVIEW);
 767         glLoadIdentity();
 768         glScalef(GL_viewport_scale_w, GL_viewport_scale_h, 1.0f);
 769 }