testgesture.c (8458B)
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 /* Usage: 14 * Spacebar to begin recording a gesture on all touches. 15 * s to save all touches into "./gestureSave" 16 * l to load all touches from "./gestureSave" 17 */ 18 19 #include "SDL.h" 20 #include <stdlib.h> /* for exit() */ 21 22 #ifdef __EMSCRIPTEN__ 23 #include <emscripten/emscripten.h> 24 #endif 25 26 #include "SDL_test.h" 27 #include "SDL_test_common.h" 28 29 #define WIDTH 640 30 #define HEIGHT 480 31 #define BPP 4 32 33 /* MUST BE A POWER OF 2! */ 34 #define EVENT_BUF_SIZE 256 35 36 #define VERBOSE 0 37 38 static SDLTest_CommonState *state; 39 static SDL_Event events[EVENT_BUF_SIZE]; 40 static int eventWrite; 41 static int colors[7] = {0xFF,0xFF00,0xFF0000,0xFFFF00,0x00FFFF,0xFF00FF,0xFFFFFF}; 42 static int quitting = 0; 43 44 typedef struct 45 { 46 float x, y; 47 } Point; 48 49 typedef struct 50 { 51 float ang, r; 52 Point p; 53 } Knob; 54 55 static Knob knob = { 0.0f, 0.1f, { 0.0f, 0.0f } }; 56 57 58 static void 59 setpix(SDL_Surface *screen, float _x, float _y, unsigned int col) 60 { 61 Uint32 *pixmem32; 62 Uint32 colour; 63 Uint8 r, g, b; 64 const int x = (int)_x; 65 const int y = (int)_y; 66 float a; 67 68 if ( (x < 0) || (x >= screen->w) || (y < 0) || (y >= screen->h) ) { 69 return; 70 } 71 72 pixmem32 = (Uint32 *) screen->pixels + y * screen->pitch / BPP + x; 73 74 SDL_memcpy(&colour, pixmem32, screen->format->BytesPerPixel); 75 76 SDL_GetRGB(colour,screen->format,&r,&g,&b); 77 78 /* r = 0;g = 0; b = 0; */ 79 a = (float) ((col >> 24) & 0xFF); 80 if (a == 0) { 81 a = 0xFF; /* Hack, to make things easier. */ 82 } 83 84 a = (a == 0.0f) ? 1 : (a / 255.0f); 85 r = (Uint8) (r * (1 - a) + ((col >> 16) & 0xFF) * a); 86 g = (Uint8) (g * (1 - a) + ((col >> 8) & 0xFF) * a); 87 b = (Uint8) (b * (1 - a) + ((col >> 0) & 0xFF) * a); 88 colour = SDL_MapRGB(screen->format, r, g, b); 89 90 *pixmem32 = colour; 91 } 92 93 static void 94 drawLine(SDL_Surface *screen, float x0, float y0, float x1, float y1, unsigned int col) 95 { 96 float t; 97 for (t = 0; t < 1; t += (float) (1.0f / SDL_max(SDL_fabs(x0 - x1), SDL_fabs(y0 - y1)))) { 98 setpix(screen, x1 + t * (x0 - x1), y1 + t * (y0 - y1), col); 99 } 100 } 101 102 static void 103 drawCircle(SDL_Surface *screen, float x, float y, float r, unsigned int c) 104 { 105 float tx,ty, xr; 106 for (ty = (float) -SDL_fabs(r); ty <= (float) SDL_fabs((int) r); ty++) { 107 xr = (float) SDL_sqrt(r * r - ty * ty); 108 if (r > 0) { /* r > 0 ==> filled circle */ 109 for(tx = -xr + 0.5f; tx <= xr - 0.5f; tx++) { 110 setpix(screen, x + tx, y + ty, c); 111 } 112 } else { 113 setpix(screen, x - xr + 0.5f, y + ty, c); 114 setpix(screen, x + xr - 0.5f, y + ty, c); 115 } 116 } 117 } 118 119 static void 120 drawKnob(SDL_Surface *screen, const Knob *k) 121 { 122 drawCircle(screen, k->p.x * screen->w, k->p.y * screen->h, k->r * screen->w, 0xFFFFFF); 123 drawCircle(screen, (k->p.x + k->r / 2 * SDL_cosf(k->ang)) * screen->w, 124 (k->p.y + k->r / 2 * SDL_sinf(k->ang)) * screen->h, k->r / 4 * screen->w, 0); 125 } 126 127 static void 128 DrawScreen(SDL_Window *window) 129 { 130 SDL_Surface *screen = SDL_GetWindowSurface(window); 131 int i; 132 133 if (!screen) { 134 return; 135 } 136 137 SDL_FillRect(screen, NULL, SDL_MapRGB(screen->format, 75, 75, 75)); 138 139 /* draw Touch History */ 140 for (i = eventWrite; i < eventWrite + EVENT_BUF_SIZE; ++i) { 141 const SDL_Event *event = &events[i & (EVENT_BUF_SIZE - 1)]; 142 const float age = (float)(i - eventWrite) / EVENT_BUF_SIZE; 143 float x, y; 144 unsigned int c, col; 145 146 if ( (event->type == SDL_FINGERMOTION) || 147 (event->type == SDL_FINGERDOWN) || 148 (event->type == SDL_FINGERUP) ) { 149 x = event->tfinger.x; 150 y = event->tfinger.y; 151 152 /* draw the touch: */ 153 c = colors[event->tfinger.fingerId % 7]; 154 col = ((unsigned int) (c * (0.1f + 0.85f))) | (unsigned int) (0xFF * age) << 24; 155 156 if (event->type == SDL_FINGERMOTION) { 157 drawCircle(screen, x * screen->w, y * screen->h, 5, col); 158 } else if (event->type == SDL_FINGERDOWN) { 159 drawCircle(screen, x * screen->w, y * screen->h, -10, col); 160 } 161 } 162 } 163 164 if (knob.p.x > 0) { 165 drawKnob(screen, &knob); 166 } 167 168 SDL_UpdateWindowSurface(window); 169 } 170 171 static void 172 loop(void) 173 { 174 SDL_Event event; 175 SDL_RWops *stream; 176 int i; 177 178 while (SDL_PollEvent(&event)) { 179 SDLTest_CommonEvent(state, &event, &quitting); 180 181 /* Record _all_ events */ 182 events[eventWrite & (EVENT_BUF_SIZE-1)] = event; 183 eventWrite++; 184 185 switch (event.type) { 186 case SDL_KEYDOWN: 187 switch (event.key.keysym.sym) { 188 case SDLK_i: { 189 for (i = 0; i < SDL_GetNumTouchDevices(); ++i) { 190 const SDL_TouchID id = SDL_GetTouchDevice(i); 191 SDL_Log("Fingers Down on device %"SDL_PRIs64": %d", id, SDL_GetNumTouchFingers(id)); 192 } 193 break; 194 } 195 196 case SDLK_SPACE: 197 SDL_RecordGesture(-1); 198 break; 199 200 case SDLK_s: 201 stream = SDL_RWFromFile("gestureSave", "w"); 202 SDL_Log("Wrote %i templates", SDL_SaveAllDollarTemplates(stream)); 203 SDL_RWclose(stream); 204 break; 205 206 case SDLK_l: 207 stream = SDL_RWFromFile("gestureSave", "r"); 208 SDL_Log("Loaded: %i", SDL_LoadDollarTemplates(-1, stream)); 209 SDL_RWclose(stream); 210 break; 211 } 212 break; 213 214 #if VERBOSE 215 case SDL_FINGERMOTION: 216 SDL_Log("Finger: %"SDL_PRIs64",x: %f, y: %f",event.tfinger.fingerId, 217 event.tfinger.x,event.tfinger.y); 218 break; 219 220 case SDL_FINGERDOWN: 221 SDL_Log("Finger: %"SDL_PRIs64" down - x: %f, y: %f", 222 event.tfinger.fingerId,event.tfinger.x,event.tfinger.y); 223 break; 224 225 case SDL_FINGERUP: 226 SDL_Log("Finger: %"SDL_PRIs64" up - x: %f, y: %f", 227 event.tfinger.fingerId,event.tfinger.x,event.tfinger.y); 228 break; 229 #endif 230 231 case SDL_MULTIGESTURE: 232 #if VERBOSE 233 SDL_Log("Multi Gesture: x = %f, y = %f, dAng = %f, dR = %f", 234 event.mgesture.x, event.mgesture.y, 235 event.mgesture.dTheta, event.mgesture.dDist); 236 SDL_Log("MG: numDownTouch = %i",event.mgesture.numFingers); 237 #endif 238 239 knob.p.x = event.mgesture.x; 240 knob.p.y = event.mgesture.y; 241 knob.ang += event.mgesture.dTheta; 242 knob.r += event.mgesture.dDist; 243 break; 244 245 case SDL_DOLLARGESTURE: 246 SDL_Log("Gesture %"SDL_PRIs64" performed, error: %f", 247 event.dgesture.gestureId, event.dgesture.error); 248 break; 249 250 case SDL_DOLLARRECORD: 251 SDL_Log("Recorded gesture: %"SDL_PRIs64"",event.dgesture.gestureId); 252 break; 253 } 254 } 255 256 for (i = 0; i < state->num_windows; ++i) { 257 if (state->windows[i]) { 258 DrawScreen(state->windows[i]); 259 } 260 } 261 262 #ifdef __EMSCRIPTEN__ 263 if (quitting) { 264 emscripten_cancel_main_loop(); 265 } 266 #endif 267 } 268 269 int main(int argc, char* argv[]) 270 { 271 state = SDLTest_CommonCreateState(argv, SDL_INIT_VIDEO); 272 if (!state) { 273 return 1; 274 } 275 276 state->window_title = "Gesture Test"; 277 state->window_w = WIDTH; 278 state->window_h = HEIGHT; 279 state->skip_renderer = SDL_TRUE; 280 281 if (!SDLTest_CommonDefaultArgs(state, argc, argv) || !SDLTest_CommonInit(state)) { 282 SDLTest_CommonQuit(state); 283 return 1; 284 } 285 286 #ifdef __EMSCRIPTEN__ 287 emscripten_set_main_loop(loop, 0, 1); 288 #else 289 while (!quitting) { 290 loop(); 291 } 292 #endif 293 294 SDLTest_CommonQuit(state); 295 return 0; 296 } 297