SDL  2.0
testgesture.c
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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 
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;
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
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
129 {
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 
169 }
170 
171 static void
172 loop(void)
173 {
175  SDL_RWops *stream;
176  int i;
177 
178  while (SDL_PollEvent(&event)) {
180 
181  /* Record _all_ events */
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));
204  break;
205 
206  case SDLK_l:
207  stream = SDL_RWFromFile("gestureSave", "r");
208  SDL_Log("Loaded: %i", SDL_LoadDollarTemplates(-1, 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]) {
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 {
272  if (!state) {
273  return 1;
274  }
275 
276  state->window_title = "Gesture Test";
277  state->window_w = WIDTH;
278  state->window_h = HEIGHT;
280 
281  if (!SDLTest_CommonDefaultArgs(state, argc, argv) || !SDLTest_CommonInit(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 
295  return 0;
296 }
297 
SDL.h
SDLK_SPACE
@ SDLK_SPACE
Definition: SDL_keycode.h:58
EVENT_BUF_SIZE
#define EVENT_BUF_SIZE
Definition: testgesture.c:34
c
const GLubyte * c
Definition: SDL_opengl_glext.h:11096
SDLTest_CommonState::windows
SDL_Window ** windows
Definition: SDL_test_common.h:78
Knob::p
Point p
Definition: testgesture.c:52
Uint32
uint32_t Uint32
Definition: SDL_stdinc.h:203
SDL_sinf
#define SDL_sinf
Definition: SDL_dynapi_overrides.h:436
screen
SDL_Renderer * screen
Definition: testgamecontroller.c:64
knob
static Knob knob
Definition: testgesture.c:55
SDL_Surface
A collection of pixels used in software blitting.
Definition: SDL_surface.h:70
SDL_PollEvent
#define SDL_PollEvent
Definition: SDL_dynapi_overrides.h:122
SDL_test.h
SDL_fabs
#define SDL_fabs
Definition: SDL_dynapi_overrides.h:430
main
int main(int argc, char *argv[])
Definition: testgesture.c:269
NULL
#define NULL
Definition: begin_code.h:167
b
GLboolean GLboolean GLboolean b
Definition: SDL_opengl_glext.h:1112
g
GLboolean GLboolean g
Definition: SDL_opengl_glext.h:1112
SDLTest_CommonState
Definition: SDL_test_common.h:51
SDL_DOLLARRECORD
@ SDL_DOLLARRECORD
Definition: SDL_events.h:134
drawCircle
static void drawCircle(SDL_Surface *screen, float x, float y, float r, unsigned int c)
Definition: testgesture.c:103
Point::x
float x
Definition: testgesture.c:46
SDLK_l
@ SDLK_l
Definition: SDL_keycode.h:111
SDLTest_CommonState::skip_renderer
SDL_bool skip_renderer
Definition: SDL_test_common.h:83
ty
GLbyte ty
Definition: SDL_opengl_glext.h:5975
x0
GLuint GLfloat x0
Definition: SDL_opengl_glext.h:8586
r
GLdouble GLdouble GLdouble r
Definition: SDL_opengl.h:2079
Knob::ang
float ang
Definition: testgesture.c:51
WIDTH
#define WIDTH
Definition: testgesture.c:29
SDL_RecordGesture
#define SDL_RecordGesture
Definition: SDL_dynapi_overrides.h:155
SDL_TouchID
Sint64 SDL_TouchID
Definition: SDL_touch.h:41
stream
GLuint GLuint stream
Definition: SDL_opengl_glext.h:1779
SDL_GetNumTouchDevices
#define SDL_GetNumTouchDevices
Definition: SDL_dynapi_overrides.h:489
y0
GLuint GLfloat GLfloat y0
Definition: SDL_opengl_glext.h:8586
x1
GLuint GLfloat GLfloat GLfloat x1
Definition: SDL_opengl_glext.h:8586
a
GLboolean GLboolean GLboolean GLboolean a
Definition: SDL_opengl_glext.h:1112
SDL_KEYDOWN
@ SDL_KEYDOWN
Definition: SDL_events.h:96
setpix
static void setpix(SDL_Surface *screen, float _x, float _y, unsigned int col)
Definition: testgesture.c:59
SDLTest_CommonCreateState
SDLTest_CommonState * SDLTest_CommonCreateState(char **argv, Uint32 flags)
Parse command line parameters and create common state.
Definition: SDL_test_common.c:59
SDL_Window
The type used to identify a window.
Definition: SDL_sysvideo.h:74
SDL_UpdateWindowSurface
#define SDL_UpdateWindowSurface
Definition: SDL_dynapi_overrides.h:541
SDLK_s
@ SDLK_s
Definition: SDL_keycode.h:118
SDLTest_CommonQuit
void SDLTest_CommonQuit(SDLTest_CommonState *state)
Close test window.
Definition: SDL_test_common.c:1910
drawLine
static void drawLine(SDL_Surface *screen, float x0, float y0, float x1, float y1, unsigned int col)
Definition: testgesture.c:94
SDLTest_CommonState::window_w
int window_w
Definition: SDL_test_common.h:66
SDL_FINGERUP
@ SDL_FINGERUP
Definition: SDL_events.h:129
SDLTest_CommonState::num_windows
int num_windows
Definition: SDL_test_common.h:77
SDL_memcpy
#define SDL_memcpy
Definition: SDL_dynapi_overrides.h:387
event
struct _cl_event * event
Definition: SDL_opengl_glext.h:2652
SDLTest_CommonDefaultArgs
SDL_bool SDLTest_CommonDefaultArgs(SDLTest_CommonState *state, const int argc, char **argv)
Easy argument handling when test app doesn't need any custom args.
Definition: SDL_test_common.c:584
SDL_FINGERDOWN
@ SDL_FINGERDOWN
Definition: SDL_events.h:128
x
GLint GLint GLint GLint GLint x
Definition: SDL_opengl.h:1574
SDLK_i
@ SDLK_i
Definition: SDL_keycode.h:108
window
EGLSurface EGLNativeWindowType * window
Definition: eglext.h:1025
SDL_Log
#define SDL_Log
Definition: SDL_dynapi_overrides.h:31
SDL_test_common.h
SDL_GetTouchDevice
#define SDL_GetTouchDevice
Definition: SDL_dynapi_overrides.h:490
f
GLfloat f
Definition: SDL_opengl_glext.h:1873
t
GLdouble GLdouble t
Definition: SDL_opengl.h:2071
SDL_RWFromFile
#define SDL_RWFromFile
Definition: SDL_dynapi_overrides.h:351
SDL_max
#define SDL_max(x, y)
Definition: SDL_stdinc.h:407
DrawScreen
static void DrawScreen(SDL_Window *window)
Definition: testgesture.c:128
SDL_GetNumTouchFingers
#define SDL_GetNumTouchFingers
Definition: SDL_dynapi_overrides.h:491
SDL_FINGERMOTION
@ SDL_FINGERMOTION
Definition: SDL_events.h:130
Knob
Definition: testgesture.c:49
state
static SDLTest_CommonState * state
Definition: testgesture.c:38
loop
static void loop(void)
Definition: testgesture.c:172
SDL_SaveAllDollarTemplates
#define SDL_SaveAllDollarTemplates
Definition: SDL_dynapi_overrides.h:156
eventWrite
static int eventWrite
Definition: testgesture.c:40
SDL_GetWindowSurface
#define SDL_GetWindowSurface
Definition: SDL_dynapi_overrides.h:540
quitting
static int quitting
Definition: testgesture.c:42
SDL_cosf
#define SDL_cosf
Definition: SDL_dynapi_overrides.h:429
y
GLint GLint GLint GLint GLint GLint y
Definition: SDL_opengl.h:1574
SDL_LoadDollarTemplates
#define SDL_LoadDollarTemplates
Definition: SDL_dynapi_overrides.h:158
HEIGHT
#define HEIGHT
Definition: testgesture.c:30
SDLTest_CommonInit
SDL_bool SDLTest_CommonInit(SDLTest_CommonState *state)
Open test window.
Definition: SDL_test_common.c:835
SDL_INIT_VIDEO
#define SDL_INIT_VIDEO
Definition: SDL.h:80
SDLTest_CommonState::window_title
const char * window_title
Definition: SDL_test_common.h:61
events
static SDL_Event events[EVENT_BUF_SIZE]
Definition: testgesture.c:39
k
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int int int return Display Window Cursor return Display Window return Display Drawable GC int int unsigned int unsigned int return Display Drawable GC int int _Xconst char int return Display Drawable GC int int unsigned int unsigned int return Display return Display Cursor return Display GC return XModifierKeymap return char Display Window int return Display return Display int int int return Display long XVisualInfo int return Display Window Atom long long Bool Atom Atom int unsigned long unsigned long k)
Definition: SDL_x11sym.h:80
SDL_TRUE
@ SDL_TRUE
Definition: SDL_stdinc.h:164
SDL_sqrt
#define SDL_sqrt
Definition: SDL_dynapi_overrides.h:437
Point::y
float y
Definition: testgesture.c:46
SDL_MULTIGESTURE
@ SDL_MULTIGESTURE
Definition: SDL_events.h:135
drawKnob
static void drawKnob(SDL_Surface *screen, const Knob *k)
Definition: testgesture.c:120
SDL_RWclose
#define SDL_RWclose
Definition: SDL_dynapi_overrides.h:725
y1
GLfixed y1
Definition: SDL_opengl_glext.h:4586
SDLTest_CommonState::window_h
int window_h
Definition: SDL_test_common.h:67
BPP
#define BPP
Definition: testgesture.c:31
SDL_FillRect
#define SDL_FillRect
Definition: SDL_dynapi_overrides.h:466
SDL_MapRGB
#define SDL_MapRGB
Definition: SDL_dynapi_overrides.h:286
SDL_Event
General event structure.
Definition: SDL_events.h:558
Knob::r
float r
Definition: testgesture.c:51
SDLTest_CommonEvent
void SDLTest_CommonEvent(SDLTest_CommonState *state, SDL_Event *event, int *done)
Common event handler for test windows.
Definition: SDL_test_common.c:1579
Point
Definition: testgesture.c:44
SDL_PRIs64
#define SDL_PRIs64
Definition: SDL_stdinc.h:227
SDL_RWops
Definition: SDL_rwops.h:52
SDL_DOLLARGESTURE
@ SDL_DOLLARGESTURE
Definition: SDL_events.h:133
SDL_GetRGB
#define SDL_GetRGB
Definition: SDL_dynapi_overrides.h:288
i
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:50
colors
static int colors[7]
Definition: testgesture.c:41
Uint8
uint8_t Uint8
Definition: SDL_stdinc.h:179