graphics.cc

   1
   2 /**
   3  *
   4  * Tennix! SDL Port
   5  * Copyright (C) 2003, 2007, 2008, 2009 Thomas Perl <thp@thpinfo.com>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version 2
  10  * of the License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  20  * MA  02110-1301, USA.
  21  *
  22  **/
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <math.h>
  27 #include <unistd.h>
  28 #include <assert.h>
  29 #include <ctype.h>
  30 #include <string.h>
  31 #include <assert.h>
  32
  33 #include "tennix.h"
  34 #include "graphics.h"
  35 #include "archive.hh"
  36 #include "sound.h"
  37
  38 #include "SDL_rotozoom.h"
  39
  40 static Image* images;
  41
  42 static Font* fonts;
  43 FreeList* font_freelist = NULL;
  44
  45 static FontDescription font_desc[] = {
  46     /**
  47      * This is the list of fonts to be loaded. Be sure to
  48      * use NULL as filename when using the same .ttf file
  49      * the second time in a row - this saves memory in the
  50      * loader function.
  51      **/
  52     { "dustismo.ttf", 15, TTF_STYLE_NORMAL },
  53     { NULL, 20, TTF_STYLE_NORMAL },
  54     { "itwasntme.ttf", 22, TTF_STYLE_NORMAL },
  55     { NULL, 28, TTF_STYLE_NORMAL }
  56 };
  57
  58 static SDL_Surface *buffer;
  59 static SDL_Surface *background;
  60
  61 static SDL_Rect *rect_update_cache;
  62 static SDL_Rect *rect_update_old;
  63 static int rect_update_cache_current;
  64 static int rect_update_old_count;
  65
  66 Uint32 fading_start = 0;
  67
  68 static const char* graphics[] = {
  69     "court.png",
  70     "shadow.png",
  71     "player-racket.png",
  72     "ball.png",
  73     "referee.png",
  74     "ctt_hard.png",
  75     "ctt_clay.png",
  76     "ctt_grass.png",
  77     "sidebar.png",
  78     "tennixlogo.png",
  79     "btnplay.png",
  80     "btnresume.png",
  81     "btnquit.png",
  82     "stadium.png",
  83     "fog.png",
  84     "fog2.png",
  85     "night.png",
  86     "talk.png",
  87     "cursor.png",
  88     "worldmap.png",
  89     "input_gamepad.png",
  90     "input_keyboard_arrows.png",
  91     "input_keyboard_ol.png",
  92     "input_keyboard_ws.png",
  93     "input_maemo_dpad.png",
  94     "input_mouse.png",
  95     "input_touchscreen.png",
  96     "input_ai.png",
  97     "back.png",
  98     "forward.png",
  99     "loc_margaret_court_arena.png",
 100     "loc_stade_roland_garros.png",
 101     "loc_court_no_1.png",
 102     "loc_arthur_ashe_stadium.png",
 103 #ifdef NONFREE_LOCATIONS
 104     "loc_training_camp.png",
 105     "loc_austrian_open.png",
 106     "loc_olympic_green_tennis.png"
 107 #endif
 108 };
 109
 110 void init_graphics(TennixArchive& tnxar) {
 111     int i;
 112     char *d;
 113     SDL_Surface* data;
 114     SDL_Surface* tmp;
 115     struct SDL_RWops* rw;
 116     const char* font_data = NULL;
 117
 118     if (TTF_Init() == -1) {
 119         fprintf(stderr, "Cannot init TTF: %s\n", TTF_GetError());
 120         exit(EXIT_FAILURE);
 121     }
 122
 123     rect_update_cache = (SDL_Rect*)calloc(RECT_UPDATE_CACHE, sizeof(SDL_Rect));
 124     rect_update_old = (SDL_Rect*)calloc(RECT_UPDATE_CACHE, sizeof(SDL_Rect));
 125     rect_update_cache_current = 0;
 126     rect_update_old_count = 0;
 127
 128     images = (Image*)calloc( GR_COUNT, sizeof( Image));
 129     fonts = (Font*)calloc(FONT_COUNT, sizeof(Font));
 130
 131     buffer = SDL_CreateRGBSurface(SDL_SWSURFACE, WIDTH, HEIGHT,
 132                  screen->format->BitsPerPixel,
 133                  screen->format->Rmask,
 134                  screen->format->Gmask,
 135                  screen->format->Bmask,
 136                  screen->format->Amask);
 137
 138     background = SDL_CreateRGBSurface(SDL_SWSURFACE, WIDTH, HEIGHT,
 139                      screen->format->BitsPerPixel,
 140                      screen->format->Rmask,
 141                      screen->format->Gmask,
 142                      screen->format->Bmask,
 143                      screen->format->Amask);
 144
 145     if( buffer == NULL) {
 146         fprintf( stderr, "Cannot create buffer surface: %s\n", SDL_GetError());
 147     }
 148
 149     font_freelist = freelist_create();
 150
 151     /* Load fonts from resource file */
 152     for (i=0; i<FONT_COUNT; i++) {
 153         if (font_desc[i].filename != NULL) {
 154             assert(tnxar.setItemFilename(font_desc[i].filename) != 0);
 155             font_data = tnxar.getItemBytes();
 156             freelist_append(font_freelist, font_data);
 157         }
 158         assert(font_data != NULL);
 159         rw = SDL_RWFromMem((void*)font_data, tnxar.getItemSize());
 160         fonts[i].data = TTF_OpenFontRW(rw, 1, font_desc[i].size);
 161         if (fonts[i].data == NULL) {
 162             fprintf(stderr, "TTF error: %s\n", TTF_GetError());
 163             assert(fonts[i].data != NULL);
 164         }
 165         TTF_SetFontStyle(fonts[i].data, font_desc[i].style);
 166     }
 167
 168     draw_button(40, (HEIGHT-40)/2, WIDTH-80, 40, 100, 100, 100, 1);
 169     store_screen();
 170     updatescr();
 171
 172     for( i=0; i<GR_COUNT; i++) {
 173         if (tnxar.setItemFilename(graphics[i]) != 0 ) {
 174             d = tnxar.getItemBytes();
 175             tmp = IMG_Load_RW(SDL_RWFromMem(d, tnxar.getItemSize()), 1);
 176             free(d);
 177         } else {
 178             fprintf(stderr, "Cannot find file: %s\n", graphics[i]);
 179             exit(EXIT_FAILURE);
 180         }
 181         if( !tmp) {
 182             fprintf( stderr, "Error: %s\n", SDL_GetError());
 183             continue;
 184         }
 185
 186         /* Convert to RGBA in the display format */
 187         data = SDL_DisplayFormatAlpha(tmp);
 188         SDL_FreeSurface(tmp);
 189
 190         if( !data) {
 191             fprintf( stderr, "Error: %s\n", SDL_GetError());
 192             continue;
 193         }
 194         images[i].data = data;
 195
 196         draw_button(40, (HEIGHT-40)/2, (WIDTH-80)*i/(GR_COUNT+SOUND_MAX), 40, 100, 250, 100, 0);
 197         rectangle(40+BUTTON_BORDER*2, (HEIGHT-40)/2+20+BUTTON_BORDER, (WIDTH-80)*i/(GR_COUNT+SOUND_MAX)-BUTTON_BORDER*2, 10, 170, 250, 170);
 198         updatescr();
 199     }
 200 }
 201
 202 void uninit_graphics() {
 203     int i;
 204
 205     for( i=0; i<GR_COUNT; i++) {
 206         SDL_FreeSurface( images[i].data);
 207     }
 208
 209     if( buffer != NULL) {
 210         SDL_FreeSurface( buffer);
 211     }
 212
 213     if (background != NULL) {
 214         SDL_FreeSurface(background);
 215     }
 216
 217     free(rect_update_cache);
 218     free(rect_update_old);
 219     free(images);
 220
 221     for (i=0; i<FONT_COUNT; i++) {
 222         TTF_CloseFont(fonts[i].data);
 223         fonts[i].data = NULL;
 224     }
 225     free(fonts);
 226
 227     freelist_free_all(font_freelist);
 228
 229     TTF_Quit();
 230 }
 231
 232
 233 FreeList* freelist_create()
 234 {
 235     FreeList* list = (FreeList*)malloc(sizeof(FreeList));
 236     assert(list != NULL);
 237
 238     list->head = NULL;
 239
 240     return list;
 241 }
 242
 243 void freelist_append(FreeList* list, const char* data)
 244 {
 245     FreeListItem* new_item = (FreeListItem*)malloc(sizeof(FreeListItem));
 246
 247     assert(list != NULL);
 248     assert(data != NULL);
 249
 250     new_item->data = data;
 251
 252     /* Insert item at the beginning of list */
 253     new_item->next = list->head;
 254     list->head = new_item;
 255 }
 256
 257 void freelist_free_all(FreeList* list)
 258 {
 259     FreeListItem* next;
 260
 261     assert(list != NULL);
 262
 263     while (list->head != NULL) {
 264         /* Remove one item from the head of the list */
 265         next = list->head->next;
 266         free((void*)list->head->data);
 267         free(list->head);
 268         list->head = next;
 269     }
 270
 271     free(list);
 272 }
 273
 274
 275 int get_image_width( image_id id) {
 276     return images[id].data->w;
 277 }
 278
 279 int get_image_height( image_id id) {
 280     return images[id].data->h;
 281 }
 282
 283 int get_sprite_width( image_id id, int items) {
 284     return images[id].data->w / items;
 285 }
 286
 287 void show_sprite( image_id id, int pos, int items, int x_offset,
 288         int y_offset, int opacity)
 289 {
 290     assert(id < GR_COUNT);
 291     SDL_SetAlpha(images[id].data, SDL_SRCALPHA | SDL_RLEACCEL, opacity);
 292     blit_surface(images[id].data, x_offset, y_offset, pos, items);
 293 }
 294
 295 void show_image_rotozoom(image_id id, int x, int y, float rotate, float zoom)
 296 {
 297     SDL_Surface* tmp;
 298     SDL_Rect src, dst;
 299
 300     assert(id < GR_COUNT);
 301
 302     tmp = rotozoomSurface(images[id].data, rotate, zoom, SMOOTHING_OFF);
 303
 304     dst.w = src.w = tmp->w;
 305     dst.h = src.h = tmp->h;
 306     src.x = 0;
 307     src.y = 0;
 308     dst.x = x - src.w/2;
 309     dst.y = y - src.h/2;
 310
 311     SDL_BlitSurface(tmp, &src, screen, &dst);
 312     update_rect2(dst);
 313     SDL_FreeSurface(tmp);
 314 }
 315
 316 void fill_image_offset( image_id id, int x, int y, int w, int h, int offset_x, int offset_y) {
 317     SDL_Surface *bitmap;
 318     SDL_Rect src, dst;
 319     int dx = 0, dy = 0, cx, cy;
 320
 321     if( id >= GR_COUNT) return;
 322
 323     bitmap = images[id].data;
 324
 325     /* Make negative offsets positive */
 326     if (offset_x < 0) {
 327         offset_x = (offset_x%bitmap->w)+bitmap->w;
 328     }
 329     if (offset_y < 0) {
 330         offset_y = (offset_y%bitmap->h)+bitmap->h;
 331     }
 332
 333     src.y = offset_y % bitmap->h;
 334     while( dy < h) {
 335         src.h = dst.h = cy = (h-dy > bitmap->h-src.y)?(bitmap->h-src.y):(h-dy);
 336         dst.y = y+dy;
 337
 338         dx = 0;
 339         src.x = offset_x % bitmap->w;
 340         while( dx < w) {
 341             src.w = dst.w = cx = (w-dx > bitmap->w-src.x)?(bitmap->w-src.x):(w-dx);
 342             dst.x = x+dx;
 343
 344             SDL_BlitSurface( bitmap, &src, screen, &dst);
 345             update_rect2(dst);
 346
 347             dx += cx;
 348             src.x = 0;
 349         }
 350
 351         dy += cy;
 352         src.y = 0;
 353     }
 354 }
 355
 356 void line_horiz( int y, Uint8 r, Uint8 g, Uint8 b) {
 357     rectangle(0, y, screen->w, 1, r, g, b);
 358 }
 359
 360 void line_vert( int x, Uint8 r, Uint8 g, Uint8 b) {
 361     rectangle(x, 0, 1, screen->h, r, g, b);
 362 }
 363
 364 void rectangle( int x, int y, int w, int h, Uint8 r, Uint8 g, Uint8 b) {
 365     Uint32 color;
 366     SDL_Rect rect;
 367
 368     if (w <= 0 || h <= 0 || x < 0 || y < 0 || x+w > WIDTH || y+h > HEIGHT) {
 369         return;
 370     }
 371
 372     color = SDL_MapRGB(screen->format, r, g, b);
 373
 374     rect.x = x;
 375     rect.y = y;
 376     rect.w = w;
 377     rect.h = h;
 378
 379     SDL_FillRect( screen, &rect, color);
 380     update_rect(x, y, w, h);
 381 }
 382
 383 void rectangle_alpha(int x, int y, int w, int h, Uint8 r, Uint8 g, Uint8 b, Uint8 opacity)
 384 {
 385     Uint32 color;
 386     SDL_Surface *buf;
 387     SDL_Rect rect, rect2;
 388
 389     if (w <= 0 || h <= 0 || x < 0 || y < 0 || x+w > WIDTH || y+h > HEIGHT) {
 390         return;
 391     }
 392
 393     color = SDL_MapRGB(screen->format, r, g, b);
 394
 395     buf = SDL_CreateRGBSurface(SDL_SWSURFACE, w, h,
 396                  screen->format->BitsPerPixel,
 397                  screen->format->Rmask,
 398                  screen->format->Gmask,
 399                  screen->format->Bmask,
 400                  screen->format->Amask);
 401
 402     rect.x = rect.y = 0;
 403     rect2.x = x;
 404     rect2.y = y;
 405     rect.w = rect2.w = w;
 406     rect.h = rect2.h = h;
 407
 408     SDL_FillRect(buf, &rect, color);
 409     SDL_SetAlpha(buf, SDL_RLEACCEL | SDL_SRCALPHA, opacity);
 410     SDL_BlitSurface(buf, &rect, screen, &rect2);
 411     update_rect(x, y, w, h);
 412
 413     SDL_FreeSurface(buf);
 414 }
 415
 416 void draw_button( int x, int y, int w, int h, Uint8 r, Uint8 g, Uint8 b, char pressed) {
 417     float diff = (pressed?1.0-BUTTON_HIGHLIGHT:1.0+BUTTON_HIGHLIGHT);
 418     rectangle(x, y, w, h, MIN(r*diff, 255), MIN(g*diff, 255), MIN(b*diff, 255));
 419     rectangle(x+BUTTON_BORDER, y+BUTTON_BORDER, w-BUTTON_BORDER, h-BUTTON_BORDER, MIN(r/diff, 255), MIN(g/diff, 255), MIN(b/diff, 255));
 420     rectangle(x+BUTTON_BORDER, y+BUTTON_BORDER, w-2*BUTTON_BORDER, h-2*BUTTON_BORDER, r, g, b);
 421 }
 422
 423 void draw_button_text(const char* s, int x, int y, int w, int h, Uint8 r, Uint8 g, Uint8 b, char pressed) {
 424     int font_x, font_y;
 425     float factor = 0.3;
 426     pressed = pressed?1:0;
 427     draw_button( x, y, w, h, r, g, b, pressed);
 428     font_x = x + w/2 - font_get_string_width(FONT_SMALL, s)/2 + pressed*BUTTON_BORDER;
 429     font_y = y + h/2 - font_get_height(FONT_SMALL)/2 + pressed*BUTTON_BORDER;
 430     font_draw_string_color(FONT_SMALL, s, font_x, font_y, (Uint8)(r*factor), (Uint8)(g*factor), (Uint8)(b*factor));
 431 }
 432
 433 void draw_button_object(MenuButton* b, int mx, int my)
 434 {
 435     if (b->image_id == GR_COUNT) {
 436         draw_button_text(b->text, b->x, b->y, b->w, b->h, b->r, b->g, b->b, M_POS_BUTTON(*b, mx, my));
 437     } else {
 438         show_image_rotozoom(b->image_id, b->x+b->w/2, b->y+b->h/2, 0.0, 1.0-0.2*!M_POS_BUTTON(*b, mx, my));
 439     }
 440 }
 441
 442 void clear_screen()
 443 {
 444     SDL_Rect rect;
 445
 446     rect.x = rect.y = 0;
 447     rect.w = WIDTH;
 448     rect.h = HEIGHT;
 449
 450     SDL_FillRect(screen, &rect, SDL_MapRGB(screen->format, 0, 0, 0));
 451 }
 452
 453 void store_screen()
 454 {
 455     SDL_BlitSurface(screen, NULL, background, NULL);
 456     rect_update_old[0].x = rect_update_old[0].y = 0;
 457     rect_update_old[0].w = WIDTH;
 458     rect_update_old[0].h = HEIGHT;
 459     rect_update_old_count = 1;
 460     rect_update_cache_current = 0;
 461 }
 462
 463 void reset_screen()
 464 {
 465     int i;
 466     SDL_Rect* tmp;
 467     SDL_BlitSurface(background, NULL, screen, NULL);
 468
 469     for (i=0; i<rect_update_cache_current; i++) {
 470         SDL_BlitSurface(background, &rect_update_cache[i], screen, &rect_update_cache[i]);
 471     }
 472
 473     /* Save rects I've just updated for redraw later */
 474     tmp = rect_update_cache;
 475     rect_update_cache = rect_update_old;
 476     rect_update_old = tmp;
 477     rect_update_old_count = rect_update_cache_current;
 478     rect_update_cache_current = 0;
 479 }
 480
 481 void update_rect(Sint32 x, Sint32 y, Sint32 w, Sint32 h)
 482 {
 483     SDL_Rect* u = NULL;
 484     static int inside = 0;
 485     if (inside) return;
 486     inside = 1;
 487
 488 #ifdef DRAW_UPDATE_RECTANGLE
 489     rectangle(x, y, w, h, 50+rand()%200, 50+rand()%200 ,50+rand()%200);
 490 #endif
 491
 492     if ((x >= WIDTH) | (y >= HEIGHT) | (x+w <= 0) | (y+h <= 0) | (!w) | (!h)) {
 493         inside = 0;
 494         return;
 495     }
 496
 497     if (rect_update_cache_current == RECT_UPDATE_CACHE) {
 498         fprintf(stderr, "Overflow\n");
 499         rect_update_cache_current = 0;
 500     }
 501
 502     u = &(rect_update_cache[rect_update_cache_current]);
 503
 504     if (x < 0/* && x+w > 0*/) {
 505         w += x;
 506         x = 0;
 507     }
 508     if (y < 0/* && y+h > 0*/) {
 509         h += y;
 510         y = 0;
 511     }
 512
 513     if (x+w >= WIDTH) {
 514         w -= (x+w-WIDTH+1);
 515     }
 516
 517     if (y+h >= HEIGHT) {
 518         h -= (y+h-HEIGHT+1);
 519     }
 520
 521     if (w==0 || h==0) {
 522         inside = 0;
 523         return;
 524     }
 525
 526     u->x = x;
 527     u->y = y;
 528     u->w = w;
 529     u->h = h;
 530
 531     rect_update_cache_current++;
 532
 533     inside = 0;
 534 }
 535
 536 void updatescr()
 537 {
 538     Uint32 ticks = SDL_GetTicks();
 539     SDL_Rect *r_current = NULL, *end_current = NULL;
 540     SDL_Rect *r_old = NULL;
 541
 542     static int fading_last_time = 0;
 543     unsigned char fading_now = ticks < fading_start+FADE_DURATION;
 544
 545     if (fading_now) {
 546         SDL_SetAlpha(buffer, SDL_SRCALPHA | SDL_RLEACCEL, 255-255*(ticks-fading_start)/FADE_DURATION);
 547         SDL_BlitSurface(buffer, NULL, screen, NULL);
 548         SDL_UpdateRect(screen, 0, 0, 0, 0);
 549     } else if (fading_last_time && !fading_now) {
 550         SDL_UpdateRect(screen, 0, 0, 0, 0);
 551     } else {
 552         if (rect_update_old_count == rect_update_cache_current) {
 553             /* Merge rects into one single rect list */
 554             r_old = rect_update_old;
 555             r_current = rect_update_cache;
 556             end_current = rect_update_cache + rect_update_cache_current;
 557             while (r_current != end_current) {
 558                 r_old->w = MAX(r_current->x+r_current->w, r_old->x+r_old->w);
 559                 r_old->h = MAX(r_current->y+r_current->h, r_old->y+r_old->h);
 560                 r_old->x = MIN(r_current->x, r_old->x);
 561                 r_old->y = MIN(r_current->y, r_old->y);
 562                 r_old->w -= r_old->x;
 563                 r_old->h -= r_old->y;
 564
 565                 r_current++;
 566                 r_old++;
 567             }
 568             SDL_UpdateRects(screen, rect_update_old_count, rect_update_old);
 569         } else {
 570             SDL_UpdateRects(screen, rect_update_old_count, rect_update_old);
 571             SDL_UpdateRects(screen, rect_update_cache_current, rect_update_cache);
 572         }
 573     }
 574
 575     reset_screen();
 576     fading_last_time = fading_now;
 577 }
 578
 579 void start_fade() {
 580     SDL_BlitSurface( screen, NULL, buffer, NULL);
 581     fading_start = SDL_GetTicks();
 582 }
 583
 584 SDL_Surface* font_render_surface(font_id id, const char* text, Uint8 r,
 585         Uint8 g, Uint8 b)
 586 {
 587     SDL_Surface *result;
 588     SDL_Color color;
 589
 590     color.r = r;
 591     color.g = g;
 592     color.b = b;
 593
 594     assert(id < FONT_COUNT);
 595
 596     result = TTF_RenderText_Blended(fonts[id].data, text, color);
 597
 598     assert(result != NULL);
 599
 600     return result;
 601 }
 602
 603 void blit_surface(SDL_Surface* surface, int x, int y, int pos, int count)
 604 {
 605     SDL_Rect src, dst;
 606
 607     dst.w = src.w = surface->w/count;
 608     dst.h = src.h = surface->h;
 609     src.x = src.w*pos;
 610     src.y = 0;
 611     dst.x = x;
 612     dst.y = y;
 613
 614     SDL_BlitSurface(surface, &src, screen, &dst);
 615     update_rect2(dst);
 616 }
 617
 618 SDL_Surface* get_surface(image_id id)
 619 {
 620     assert(id < GR_COUNT);
 621     return images[id].data;
 622 }
 623
 624 void font_draw_string_color(font_id id, const char* s, int x_offset, int y_offset, Uint8 r, Uint8 g, Uint8 b) {
 625     SDL_Surface *text;
 626
 627     text = font_render_surface(id, s, r, g, b);
 628     blit_surface_simple(text, x_offset, y_offset);
 629     SDL_FreeSurface(text);
 630 }
 631
 632 int font_get_string_width(font_id id, const char* s) {
 633     int w, h;
 634
 635     assert(id < FONT_COUNT);
 636
 637     if (TTF_SizeText(fonts[id].data, s, &w, &h) != 0) {
 638         return 0;
 639     }
 640
 641     return w;
 642 }
 643
 644 int font_get_height(font_id id) {
 645     assert(id < FONT_COUNT);
 646     return TTF_FontHeight(fonts[id].data);
 647 }
 648
 649 void draw_line_faded( int x1, int y1, int x2, int y2, int r, int g, int b, int r2, int g2, int b2) {
 650     float step, dx, dy, x = x1, y = y1;
 651     int i;
 652     char fade = (r!=r2 || g!=g2 || b!=b2);
 653
 654     step = (float)(abs(x2-x1)>abs(y2-y1)?abs(x2-x1):abs(y2-y1));
 655     dx = (float)(x2-x1) / step;
 656     dy = (float)(y2-y1) / step;
 657
 658     SDL_LockSurface( screen);
 659     for( i=0; i<step; i++) {
 660         x += dx;
 661         y += dy;
 662         if( x < 0.0 || x >= WIDTH || y < 0.0 || y >= HEIGHT) {
 663             continue;
 664         }
 665         if( fade) {
 666             SET_PIXEL_RGB( screen, (int)x, (int)y, (r*(step-i)+r2*i)/step, (g*(step-i)+g2*i)/step, (b*(step-i)+b2*i)/step);
 667         } else {
 668             SET_PIXEL_RGB( screen, (int)x, (int)y, r, g, b);
 669         }
 670     }
 671     SDL_UnlockSurface( screen);
 672 }
 673