testintersections.c (10118B)
1 /* 2 Copyright (C) 1997-2020 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 13 /* Simple program: draw as many random objects on the screen as possible */ 14 15 #include <stdlib.h> 16 #include <stdio.h> 17 #include <time.h> 18 19 #ifdef __EMSCRIPTEN__ 20 #include <emscripten/emscripten.h> 21 #endif 22 23 #include "SDL_test_common.h" 24 25 #define SWAP(typ,a,b) do{typ t=a;a=b;b=t;}while(0) 26 #define NUM_OBJECTS 100 27 28 static SDLTest_CommonState *state; 29 static int num_objects; 30 static SDL_bool cycle_color; 31 static SDL_bool cycle_alpha; 32 static int cycle_direction = 1; 33 static int current_alpha = 255; 34 static int current_color = 255; 35 static SDL_BlendMode blendMode = SDL_BLENDMODE_NONE; 36 37 int mouse_begin_x = -1, mouse_begin_y = -1; 38 int done; 39 40 void 41 DrawPoints(SDL_Renderer * renderer) 42 { 43 int i; 44 int x, y; 45 SDL_Rect viewport; 46 47 /* Query the sizes */ 48 SDL_RenderGetViewport(renderer, &viewport); 49 50 for (i = 0; i < num_objects * 4; ++i) { 51 /* Cycle the color and alpha, if desired */ 52 if (cycle_color) { 53 current_color += cycle_direction; 54 if (current_color < 0) { 55 current_color = 0; 56 cycle_direction = -cycle_direction; 57 } 58 if (current_color > 255) { 59 current_color = 255; 60 cycle_direction = -cycle_direction; 61 } 62 } 63 if (cycle_alpha) { 64 current_alpha += cycle_direction; 65 if (current_alpha < 0) { 66 current_alpha = 0; 67 cycle_direction = -cycle_direction; 68 } 69 if (current_alpha > 255) { 70 current_alpha = 255; 71 cycle_direction = -cycle_direction; 72 } 73 } 74 SDL_SetRenderDrawColor(renderer, 255, (Uint8) current_color, 75 (Uint8) current_color, (Uint8) current_alpha); 76 77 x = rand() % viewport.w; 78 y = rand() % viewport.h; 79 SDL_RenderDrawPoint(renderer, x, y); 80 } 81 } 82 83 #define MAX_LINES 16 84 int num_lines = 0; 85 SDL_Rect lines[MAX_LINES]; 86 static int 87 add_line(int x1, int y1, int x2, int y2) 88 { 89 if (num_lines >= MAX_LINES) 90 return 0; 91 if ((x1 == x2) && (y1 == y2)) 92 return 0; 93 94 SDL_Log("adding line (%d, %d), (%d, %d)\n", x1, y1, x2, y2); 95 lines[num_lines].x = x1; 96 lines[num_lines].y = y1; 97 lines[num_lines].w = x2; 98 lines[num_lines].h = y2; 99 100 return ++num_lines; 101 } 102 103 104 void 105 DrawLines(SDL_Renderer * renderer) 106 { 107 int i; 108 SDL_Rect viewport; 109 110 /* Query the sizes */ 111 SDL_RenderGetViewport(renderer, &viewport); 112 113 SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255); 114 115 for (i = 0; i < num_lines; ++i) { 116 if (i == -1) { 117 SDL_RenderDrawLine(renderer, 0, 0, viewport.w - 1, viewport.h - 1); 118 SDL_RenderDrawLine(renderer, 0, viewport.h - 1, viewport.w - 1, 0); 119 SDL_RenderDrawLine(renderer, 0, viewport.h / 2, viewport.w - 1, viewport.h / 2); 120 SDL_RenderDrawLine(renderer, viewport.w / 2, 0, viewport.w / 2, viewport.h - 1); 121 } else { 122 SDL_RenderDrawLine(renderer, lines[i].x, lines[i].y, lines[i].w, lines[i].h); 123 } 124 } 125 } 126 127 #define MAX_RECTS 16 128 int num_rects = 0; 129 SDL_Rect rects[MAX_RECTS]; 130 static int 131 add_rect(int x1, int y1, int x2, int y2) 132 { 133 if (num_rects >= MAX_RECTS) 134 return 0; 135 if ((x1 == x2) || (y1 == y2)) 136 return 0; 137 138 if (x1 > x2) 139 SWAP(int, x1, x2); 140 if (y1 > y2) 141 SWAP(int, y1, y2); 142 143 SDL_Log("adding rect (%d, %d), (%d, %d) [%dx%d]\n", x1, y1, x2, y2, 144 x2 - x1, y2 - y1); 145 146 rects[num_rects].x = x1; 147 rects[num_rects].y = y1; 148 rects[num_rects].w = x2 - x1; 149 rects[num_rects].h = y2 - y1; 150 151 return ++num_rects; 152 } 153 154 static void 155 DrawRects(SDL_Renderer * renderer) 156 { 157 SDL_SetRenderDrawColor(renderer, 255, 127, 0, 255); 158 SDL_RenderFillRects(renderer, rects, num_rects); 159 } 160 161 static void 162 DrawRectLineIntersections(SDL_Renderer * renderer) 163 { 164 int i, j; 165 166 SDL_SetRenderDrawColor(renderer, 0, 255, 55, 255); 167 168 for (i = 0; i < num_rects; i++) 169 for (j = 0; j < num_lines; j++) { 170 int x1, y1, x2, y2; 171 SDL_Rect r; 172 173 r = rects[i]; 174 x1 = lines[j].x; 175 y1 = lines[j].y; 176 x2 = lines[j].w; 177 y2 = lines[j].h; 178 179 if (SDL_IntersectRectAndLine(&r, &x1, &y1, &x2, &y2)) { 180 SDL_RenderDrawLine(renderer, x1, y1, x2, y2); 181 } 182 } 183 } 184 185 static void 186 DrawRectRectIntersections(SDL_Renderer * renderer) 187 { 188 int i, j; 189 190 SDL_SetRenderDrawColor(renderer, 255, 200, 0, 255); 191 192 for (i = 0; i < num_rects; i++) 193 for (j = i + 1; j < num_rects; j++) { 194 SDL_Rect r; 195 if (SDL_IntersectRect(&rects[i], &rects[j], &r)) { 196 SDL_RenderFillRect(renderer, &r); 197 } 198 } 199 } 200 201 void 202 loop() 203 { 204 int i; 205 SDL_Event event; 206 207 /* Check for events */ 208 while (SDL_PollEvent(&event)) { 209 SDLTest_CommonEvent(state, &event, &done); 210 switch (event.type) { 211 case SDL_MOUSEBUTTONDOWN: 212 mouse_begin_x = event.button.x; 213 mouse_begin_y = event.button.y; 214 break; 215 case SDL_MOUSEBUTTONUP: 216 if (event.button.button == 3) 217 add_line(mouse_begin_x, mouse_begin_y, event.button.x, 218 event.button.y); 219 if (event.button.button == 1) 220 add_rect(mouse_begin_x, mouse_begin_y, event.button.x, 221 event.button.y); 222 break; 223 case SDL_KEYDOWN: 224 switch (event.key.keysym.sym) { 225 case 'l': 226 if (event.key.keysym.mod & KMOD_SHIFT) 227 num_lines = 0; 228 else 229 add_line(rand() % 640, rand() % 480, rand() % 640, 230 rand() % 480); 231 break; 232 case 'r': 233 if (event.key.keysym.mod & KMOD_SHIFT) 234 num_rects = 0; 235 else 236 add_rect(rand() % 640, rand() % 480, rand() % 640, 237 rand() % 480); 238 break; 239 } 240 break; 241 default: 242 break; 243 } 244 } 245 for (i = 0; i < state->num_windows; ++i) { 246 SDL_Renderer *renderer = state->renderers[i]; 247 if (state->windows[i] == NULL) 248 continue; 249 SDL_SetRenderDrawColor(renderer, 0xA0, 0xA0, 0xA0, 0xFF); 250 SDL_RenderClear(renderer); 251 252 DrawRects(renderer); 253 DrawPoints(renderer); 254 DrawRectRectIntersections(renderer); 255 DrawLines(renderer); 256 DrawRectLineIntersections(renderer); 257 258 SDL_RenderPresent(renderer); 259 } 260 #ifdef __EMSCRIPTEN__ 261 if (done) { 262 emscripten_cancel_main_loop(); 263 } 264 #endif 265 } 266 267 int 268 main(int argc, char *argv[]) 269 { 270 int i; 271 Uint32 then, now, frames; 272 273 /* Enable standard application logging */ 274 SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO); 275 276 /* Initialize parameters */ 277 num_objects = NUM_OBJECTS; 278 279 /* Initialize test framework */ 280 state = SDLTest_CommonCreateState(argv, SDL_INIT_VIDEO); 281 if (!state) { 282 return 1; 283 } 284 for (i = 1; i < argc;) { 285 int consumed; 286 287 consumed = SDLTest_CommonArg(state, i); 288 if (consumed == 0) { 289 consumed = -1; 290 if (SDL_strcasecmp(argv[i], "--blend") == 0) { 291 if (argv[i + 1]) { 292 if (SDL_strcasecmp(argv[i + 1], "none") == 0) { 293 blendMode = SDL_BLENDMODE_NONE; 294 consumed = 2; 295 } else if (SDL_strcasecmp(argv[i + 1], "blend") == 0) { 296 blendMode = SDL_BLENDMODE_BLEND; 297 consumed = 2; 298 } else if (SDL_strcasecmp(argv[i + 1], "add") == 0) { 299 blendMode = SDL_BLENDMODE_ADD; 300 consumed = 2; 301 } else if (SDL_strcasecmp(argv[i + 1], "mod") == 0) { 302 blendMode = SDL_BLENDMODE_MOD; 303 consumed = 2; 304 } 305 } 306 } else if (SDL_strcasecmp(argv[i], "--cyclecolor") == 0) { 307 cycle_color = SDL_TRUE; 308 consumed = 1; 309 } else if (SDL_strcasecmp(argv[i], "--cyclealpha") == 0) { 310 cycle_alpha = SDL_TRUE; 311 consumed = 1; 312 } else if (SDL_isdigit(*argv[i])) { 313 num_objects = SDL_atoi(argv[i]); 314 consumed = 1; 315 } 316 } 317 if (consumed < 0) { 318 static const char *options[] = { "[--blend none|blend|add|mod]", "[--cyclecolor]", "[--cyclealpha]", NULL }; 319 SDLTest_CommonLogUsage(state, argv[0], options); 320 return 1; 321 } 322 i += consumed; 323 } 324 if (!SDLTest_CommonInit(state)) { 325 return 2; 326 } 327 328 /* Create the windows and initialize the renderers */ 329 for (i = 0; i < state->num_windows; ++i) { 330 SDL_Renderer *renderer = state->renderers[i]; 331 SDL_SetRenderDrawBlendMode(renderer, blendMode); 332 SDL_SetRenderDrawColor(renderer, 0xA0, 0xA0, 0xA0, 0xFF); 333 SDL_RenderClear(renderer); 334 } 335 336 srand(time(NULL)); 337 338 /* Main render loop */ 339 frames = 0; 340 then = SDL_GetTicks(); 341 done = 0; 342 343 #ifdef __EMSCRIPTEN__ 344 emscripten_set_main_loop(loop, 0, 1); 345 #else 346 while (!done) { 347 ++frames; 348 loop(); 349 } 350 #endif 351 352 SDLTest_CommonQuit(state); 353 354 /* Print out some timing information */ 355 now = SDL_GetTicks(); 356 if (now > then) { 357 double fps = ((double) frames * 1000) / (now - then); 358 SDL_Log("%2.2f frames per second\n", fps); 359 } 360 return 0; 361 } 362 363 /* vi: set ts=4 sw=4 expandtab: */