test/testsprite2.c
author Sam Lantinga <slouken@libsdl.org>
Mon, 14 Aug 2017 05:51:44 -0700
changeset 11282 180e8906dc3c
parent 10737 3406a0f8b041
child 11811 5d94cb6b24d3
permissions -rw-r--r--
Implemented more flexible blending modes for accelerated renderers

This fixes bug 2594 - Propose new blend mode, SDL_BLENDMODE_BLEND_DSTA

blendMode = SDL_ComposeCustomBlendMode(SDL_BLENDFACTOR_SRC_ALPHA,
SDL_BLENDFACTOR_ONE_MINUS_SRC_ALPHA,
SDL_BLENDOPERATION_ADD,
SDL_BLENDFACTOR_ZERO,
SDL_BLENDFACTOR_ONE,
SDL_BLENDOPERATION_ADD);

This fixes bug 2828 - Subtractive Blending

blendMode = SDL_ComposeCustomBlendMode(SDL_BLENDFACTOR_SRC_ALPHA,
SDL_BLENDFACTOR_ONE,
SDL_BLENDOPERATION_SUBTRACT,
SDL_BLENDFACTOR_ZERO,
SDL_BLENDFACTOR_ONE,
SDL_BLENDOPERATION_SUBTRACT);


This goes partway to fixing bug 3684 - Add support for a pre-multiplied alpha blending mode

blendMode = SDL_ComposeCustomBlendMode(SDL_BLENDFACTOR_ONE,
SDL_BLENDFACTOR_ONE_MINUS_SRC_ALPHA,
SDL_BLENDOPERATION_ADD,
SDL_BLENDFACTOR_ONE,
SDL_BLENDFACTOR_ONE_MINUS_SRC_ALPHA,
SDL_BLENDOPERATION_ADD);
     1 /*
     2   Copyright (C) 1997-2017 Sam Lantinga <slouken@libsdl.org>
     3 
     4   This software is provided 'as-is', without any express or implied
     5   warranty.  In no event will the authors be held liable for any damages
     6   arising from the use of this software.
     7 
     8   Permission is granted to anyone to use this software for any purpose,
     9   including commercial applications, and to alter it and redistribute it
    10   freely.
    11 */
    12 /* Simple program:  Move N sprites around on the screen as fast as possible */
    13 
    14 #include <stdlib.h>
    15 #include <stdio.h>
    16 #include <time.h>
    17 
    18 #ifdef __EMSCRIPTEN__
    19 #include <emscripten/emscripten.h>
    20 #endif
    21 
    22 #include "SDL_test.h"
    23 #include "SDL_test_common.h"
    24 
    25 #define NUM_SPRITES    100
    26 #define MAX_SPEED     1
    27 
    28 static SDLTest_CommonState *state;
    29 static int num_sprites;
    30 static SDL_Texture **sprites;
    31 static SDL_bool cycle_color;
    32 static SDL_bool cycle_alpha;
    33 static int cycle_direction = 1;
    34 static int current_alpha = 0;
    35 static int current_color = 0;
    36 static SDL_Rect *positions;
    37 static SDL_Rect *velocities;
    38 static int sprite_w, sprite_h;
    39 static SDL_BlendMode blendMode = SDL_BLENDMODE_BLEND;
    40 
    41 /* Number of iterations to move sprites - used for visual tests. */
    42 /* -1: infinite random moves (default); >=0: enables N deterministic moves */
    43 static int iterations = -1;
    44 
    45 int done;
    46 
    47 /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
    48 static void
    49 quit(int rc)
    50 {
    51     SDL_free(sprites);
    52     SDL_free(positions);
    53     SDL_free(velocities);
    54     SDLTest_CommonQuit(state);
    55     exit(rc);
    56 }
    57 
    58 int
    59 LoadSprite(const char *file)
    60 {
    61     int i;
    62     SDL_Surface *temp;
    63 
    64     /* Load the sprite image */
    65     temp = SDL_LoadBMP(file);
    66     if (temp == NULL) {
    67         SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't load %s: %s", file, SDL_GetError());
    68         return (-1);
    69     }
    70     sprite_w = temp->w;
    71     sprite_h = temp->h;
    72 
    73     /* Set transparent pixel as the pixel at (0,0) */
    74     if (temp->format->palette) {
    75         SDL_SetColorKey(temp, 1, *(Uint8 *) temp->pixels);
    76     } else {
    77         switch (temp->format->BitsPerPixel) {
    78         case 15:
    79             SDL_SetColorKey(temp, 1, (*(Uint16 *) temp->pixels) & 0x00007FFF);
    80             break;
    81         case 16:
    82             SDL_SetColorKey(temp, 1, *(Uint16 *) temp->pixels);
    83             break;
    84         case 24:
    85             SDL_SetColorKey(temp, 1, (*(Uint32 *) temp->pixels) & 0x00FFFFFF);
    86             break;
    87         case 32:
    88             SDL_SetColorKey(temp, 1, *(Uint32 *) temp->pixels);
    89             break;
    90         }
    91     }
    92 
    93     /* Create textures from the image */
    94     for (i = 0; i < state->num_windows; ++i) {
    95         SDL_Renderer *renderer = state->renderers[i];
    96         sprites[i] = SDL_CreateTextureFromSurface(renderer, temp);
    97         if (!sprites[i]) {
    98             SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't create texture: %s\n", SDL_GetError());
    99             SDL_FreeSurface(temp);
   100             return (-1);
   101         }
   102         if (SDL_SetTextureBlendMode(sprites[i], blendMode) < 0) {
   103             SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't set blend mode: %s\n", SDL_GetError());
   104             SDL_FreeSurface(temp);
   105             SDL_DestroyTexture(sprites[i]);
   106             return (-1);
   107         }
   108     }
   109     SDL_FreeSurface(temp);
   110 
   111     /* We're ready to roll. :) */
   112     return (0);
   113 }
   114 
   115 void
   116 MoveSprites(SDL_Renderer * renderer, SDL_Texture * sprite)
   117 {
   118     int i;
   119     SDL_Rect viewport, temp;
   120     SDL_Rect *position, *velocity;
   121 
   122     /* Query the sizes */
   123     SDL_RenderGetViewport(renderer, &viewport);
   124 
   125     /* Cycle the color and alpha, if desired */
   126     if (cycle_color) {
   127         current_color += cycle_direction;
   128         if (current_color < 0) {
   129             current_color = 0;
   130             cycle_direction = -cycle_direction;
   131         }
   132         if (current_color > 255) {
   133             current_color = 255;
   134             cycle_direction = -cycle_direction;
   135         }
   136         SDL_SetTextureColorMod(sprite, 255, (Uint8) current_color,
   137                                (Uint8) current_color);
   138     }
   139     if (cycle_alpha) {
   140         current_alpha += cycle_direction;
   141         if (current_alpha < 0) {
   142             current_alpha = 0;
   143             cycle_direction = -cycle_direction;
   144         }
   145         if (current_alpha > 255) {
   146             current_alpha = 255;
   147             cycle_direction = -cycle_direction;
   148         }
   149         SDL_SetTextureAlphaMod(sprite, (Uint8) current_alpha);
   150     }
   151 
   152     /* Draw a gray background */
   153     SDL_SetRenderDrawColor(renderer, 0xA0, 0xA0, 0xA0, 0xFF);
   154     SDL_RenderClear(renderer);
   155 
   156     /* Test points */
   157     SDL_SetRenderDrawColor(renderer, 0xFF, 0x00, 0x00, 0xFF);
   158     SDL_RenderDrawPoint(renderer, 0, 0);
   159     SDL_RenderDrawPoint(renderer, viewport.w-1, 0);
   160     SDL_RenderDrawPoint(renderer, 0, viewport.h-1);
   161     SDL_RenderDrawPoint(renderer, viewport.w-1, viewport.h-1);
   162 
   163     /* Test horizontal and vertical lines */
   164     SDL_SetRenderDrawColor(renderer, 0x00, 0xFF, 0x00, 0xFF);
   165     SDL_RenderDrawLine(renderer, 1, 0, viewport.w-2, 0);
   166     SDL_RenderDrawLine(renderer, 1, viewport.h-1, viewport.w-2, viewport.h-1);
   167     SDL_RenderDrawLine(renderer, 0, 1, 0, viewport.h-2);
   168     SDL_RenderDrawLine(renderer, viewport.w-1, 1, viewport.w-1, viewport.h-2);
   169 
   170     /* Test fill and copy */
   171     SDL_SetRenderDrawColor(renderer, 0xFF, 0xFF, 0xFF, 0xFF);
   172     temp.x = 1;
   173     temp.y = 1;
   174     temp.w = sprite_w;
   175     temp.h = sprite_h;
   176     SDL_RenderFillRect(renderer, &temp);
   177     SDL_RenderCopy(renderer, sprite, NULL, &temp);
   178     temp.x = viewport.w-sprite_w-1;
   179     temp.y = 1;
   180     temp.w = sprite_w;
   181     temp.h = sprite_h;
   182     SDL_RenderFillRect(renderer, &temp);
   183     SDL_RenderCopy(renderer, sprite, NULL, &temp);
   184     temp.x = 1;
   185     temp.y = viewport.h-sprite_h-1;
   186     temp.w = sprite_w;
   187     temp.h = sprite_h;
   188     SDL_RenderFillRect(renderer, &temp);
   189     SDL_RenderCopy(renderer, sprite, NULL, &temp);
   190     temp.x = viewport.w-sprite_w-1;
   191     temp.y = viewport.h-sprite_h-1;
   192     temp.w = sprite_w;
   193     temp.h = sprite_h;
   194     SDL_RenderFillRect(renderer, &temp);
   195     SDL_RenderCopy(renderer, sprite, NULL, &temp);
   196 
   197     /* Test diagonal lines */
   198     SDL_SetRenderDrawColor(renderer, 0x00, 0xFF, 0x00, 0xFF);
   199     SDL_RenderDrawLine(renderer, sprite_w, sprite_h,
   200                        viewport.w-sprite_w-2, viewport.h-sprite_h-2);
   201     SDL_RenderDrawLine(renderer, viewport.w-sprite_w-2, sprite_h,
   202                        sprite_w, viewport.h-sprite_h-2);
   203 
   204     /* Conditionally move the sprites, bounce at the wall */
   205     if (iterations == -1 || iterations > 0) {
   206         for (i = 0; i < num_sprites; ++i) {
   207             position = &positions[i];
   208             velocity = &velocities[i];
   209             position->x += velocity->x;
   210             if ((position->x < 0) || (position->x >= (viewport.w - sprite_w))) {
   211                 velocity->x = -velocity->x;
   212                 position->x += velocity->x;
   213             }
   214             position->y += velocity->y;
   215             if ((position->y < 0) || (position->y >= (viewport.h - sprite_h))) {
   216                 velocity->y = -velocity->y;
   217                 position->y += velocity->y;
   218             }
   219 
   220         }
   221         
   222         /* Countdown sprite-move iterations and disable color changes at iteration end - used for visual tests. */
   223         if (iterations > 0) {
   224             iterations--;
   225             if (iterations == 0) {
   226                 cycle_alpha = SDL_FALSE;
   227                 cycle_color = SDL_FALSE;
   228             }
   229         }
   230     }
   231 
   232     /* Draw sprites */
   233     for (i = 0; i < num_sprites; ++i) {
   234         position = &positions[i];
   235 
   236         /* Blit the sprite onto the screen */
   237         SDL_RenderCopy(renderer, sprite, NULL, position);
   238     }
   239 
   240     /* Update the screen! */
   241     SDL_RenderPresent(renderer);
   242 }
   243 
   244 void
   245 loop()
   246 {
   247     int i;
   248     SDL_Event event;
   249 
   250     /* Check for events */
   251     while (SDL_PollEvent(&event)) {
   252         SDLTest_CommonEvent(state, &event, &done);
   253     }
   254     for (i = 0; i < state->num_windows; ++i) {
   255         if (state->windows[i] == NULL)
   256             continue;
   257         MoveSprites(state->renderers[i], sprites[i]);
   258     }
   259 #ifdef __EMSCRIPTEN__
   260     if (done) {
   261         emscripten_cancel_main_loop();
   262     }
   263 #endif
   264 }
   265 
   266 int
   267 main(int argc, char *argv[])
   268 {
   269     int i;
   270     Uint32 then, now, frames;
   271     Uint64 seed;
   272     const char *icon = "icon.bmp";
   273 
   274     /* Initialize parameters */
   275     num_sprites = NUM_SPRITES;
   276 
   277     /* Initialize test framework */
   278     state = SDLTest_CommonCreateState(argv, SDL_INIT_VIDEO);
   279     if (!state) {
   280         return 1;
   281     }
   282 
   283     for (i = 1; i < argc;) {
   284         int consumed;
   285 
   286         consumed = SDLTest_CommonArg(state, i);
   287         if (consumed == 0) {
   288             consumed = -1;
   289             if (SDL_strcasecmp(argv[i], "--blend") == 0) {
   290                 if (argv[i + 1]) {
   291                     if (SDL_strcasecmp(argv[i + 1], "none") == 0) {
   292                         blendMode = SDL_BLENDMODE_NONE;
   293                         consumed = 2;
   294                     } else if (SDL_strcasecmp(argv[i + 1], "blend") == 0) {
   295                         blendMode = SDL_BLENDMODE_BLEND;
   296                         consumed = 2;
   297                     } else if (SDL_strcasecmp(argv[i + 1], "add") == 0) {
   298                         blendMode = SDL_BLENDMODE_ADD;
   299                         consumed = 2;
   300                     } else if (SDL_strcasecmp(argv[i + 1], "mod") == 0) {
   301                         blendMode = SDL_BLENDMODE_MOD;
   302                         consumed = 2;
   303                     } else if (SDL_strcasecmp(argv[i + 1], "sub") == 0) {
   304                         blendMode = SDL_ComposeCustomBlendMode(SDL_BLENDFACTOR_SRC_ALPHA, SDL_BLENDFACTOR_ONE, SDL_BLENDOPERATION_SUBTRACT, SDL_BLENDFACTOR_ZERO, SDL_BLENDFACTOR_ONE, SDL_BLENDOPERATION_SUBTRACT);
   305                         consumed = 2;
   306                     }
   307                 }
   308             } else if (SDL_strcasecmp(argv[i], "--iterations") == 0) {
   309                 if (argv[i + 1]) {
   310                     iterations = SDL_atoi(argv[i + 1]);
   311                     if (iterations < -1) iterations = -1;
   312                     consumed = 2;
   313                 }
   314             } else if (SDL_strcasecmp(argv[i], "--cyclecolor") == 0) {
   315                 cycle_color = SDL_TRUE;
   316                 consumed = 1;
   317             } else if (SDL_strcasecmp(argv[i], "--cyclealpha") == 0) {
   318                 cycle_alpha = SDL_TRUE;
   319                 consumed = 1;
   320             } else if (SDL_isdigit(*argv[i])) {
   321                 num_sprites = SDL_atoi(argv[i]);
   322                 consumed = 1;
   323             } else if (argv[i][0] != '-') {
   324                 icon = argv[i];
   325                 consumed = 1;
   326             }
   327         }
   328         if (consumed < 0) {
   329             SDL_Log("Usage: %s %s [--blend none|blend|add|mod] [--cyclecolor] [--cyclealpha] [--iterations N] [num_sprites] [icon.bmp]\n",
   330                     argv[0], SDLTest_CommonUsage(state));
   331             quit(1);
   332         }
   333         i += consumed;
   334     }
   335     if (!SDLTest_CommonInit(state)) {
   336         quit(2);
   337     }
   338 
   339     /* Create the windows, initialize the renderers, and load the textures */
   340     sprites =
   341         (SDL_Texture **) SDL_malloc(state->num_windows * sizeof(*sprites));
   342     if (!sprites) {
   343         SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Out of memory!\n");
   344         quit(2);
   345     }
   346     for (i = 0; i < state->num_windows; ++i) {
   347         SDL_Renderer *renderer = state->renderers[i];
   348         SDL_SetRenderDrawColor(renderer, 0xA0, 0xA0, 0xA0, 0xFF);
   349         SDL_RenderClear(renderer);
   350     }
   351     if (LoadSprite(icon) < 0) {
   352         quit(2);
   353     }
   354 
   355     /* Allocate memory for the sprite info */
   356     positions = (SDL_Rect *) SDL_malloc(num_sprites * sizeof(SDL_Rect));
   357     velocities = (SDL_Rect *) SDL_malloc(num_sprites * sizeof(SDL_Rect));
   358     if (!positions || !velocities) {
   359         SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Out of memory!\n");
   360         quit(2);
   361     }
   362 
   363     /* Position sprites and set their velocities using the fuzzer */ 
   364     if (iterations >= 0) {
   365         /* Deterministic seed - used for visual tests */
   366         seed = (Uint64)iterations;
   367     } else {
   368         /* Pseudo-random seed generated from the time */
   369         seed = (Uint64)time(NULL);
   370     }
   371     SDLTest_FuzzerInit(seed);
   372     for (i = 0; i < num_sprites; ++i) {
   373         positions[i].x = SDLTest_RandomIntegerInRange(0, state->window_w - sprite_w);
   374         positions[i].y = SDLTest_RandomIntegerInRange(0, state->window_h - sprite_h);
   375         positions[i].w = sprite_w;
   376         positions[i].h = sprite_h;
   377         velocities[i].x = 0;
   378         velocities[i].y = 0;
   379         while (!velocities[i].x && !velocities[i].y) {
   380             velocities[i].x = SDLTest_RandomIntegerInRange(-MAX_SPEED, MAX_SPEED);
   381             velocities[i].y = SDLTest_RandomIntegerInRange(-MAX_SPEED, MAX_SPEED);
   382         }
   383     }
   384 
   385     /* Main render loop */
   386     frames = 0;
   387     then = SDL_GetTicks();
   388     done = 0;
   389 
   390 #ifdef __EMSCRIPTEN__
   391     emscripten_set_main_loop(loop, 0, 1);
   392 #else
   393     while (!done) {
   394         ++frames;
   395         loop();
   396     }
   397 #endif
   398 
   399     /* Print out some timing information */
   400     now = SDL_GetTicks();
   401     if (now > then) {
   402         double fps = ((double) frames * 1000) / (now - then);
   403         SDL_Log("%2.2f frames per second\n", fps);
   404     }
   405     quit(0);
   406     return 0;
   407 }
   408 
   409 /* vi: set ts=4 sw=4 expandtab: */