src/video/emscripten/SDL_emscriptenevents.c
author Charlie Birks <charlie@daftgames.net>
Tue, 29 Jan 2019 12:14:33 +0000
changeset 12570 bb39a14d510c
parent 12503 806492103856
child 12572 397aa57185c4
permissions -rw-r--r--
Emscripten: reset fullscreen_window when leaving fullscreen
If the browser left fullscreen mode by the user pressing ESC, the next
call to SDL_SetWindowFullscreen(1) will fail as it thinks the window is
already fullscreen. (#65)
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 
    22 
    23 #include "../../SDL_internal.h"
    24 
    25 #if SDL_VIDEO_DRIVER_EMSCRIPTEN
    26 
    27 #include <emscripten/html5.h>
    28 
    29 #include "../../events/SDL_events_c.h"
    30 #include "../../events/SDL_keyboard_c.h"
    31 #include "../../events/SDL_touch_c.h"
    32 
    33 #include "SDL_emscriptenevents.h"
    34 #include "SDL_emscriptenvideo.h"
    35 
    36 #include "SDL_hints.h"
    37 
    38 #define FULLSCREEN_MASK ( SDL_WINDOW_FULLSCREEN_DESKTOP | SDL_WINDOW_FULLSCREEN )
    39 
    40 /*
    41 .keyCode to scancode
    42 https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent
    43 https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/keyCode
    44 */
    45 static const SDL_Scancode emscripten_scancode_table[] = {
    46     /*  0 */    SDL_SCANCODE_UNKNOWN,
    47     /*  1 */    SDL_SCANCODE_UNKNOWN,
    48     /*  2 */    SDL_SCANCODE_UNKNOWN,
    49     /*  3 */    SDL_SCANCODE_CANCEL,
    50     /*  4 */    SDL_SCANCODE_UNKNOWN,
    51     /*  5 */    SDL_SCANCODE_UNKNOWN,
    52     /*  6 */    SDL_SCANCODE_HELP,
    53     /*  7 */    SDL_SCANCODE_UNKNOWN,
    54     /*  8 */    SDL_SCANCODE_BACKSPACE,
    55     /*  9 */    SDL_SCANCODE_TAB,
    56     /*  10 */   SDL_SCANCODE_UNKNOWN,
    57     /*  11 */   SDL_SCANCODE_UNKNOWN,
    58     /*  12 */   SDL_SCANCODE_UNKNOWN,
    59     /*  13 */   SDL_SCANCODE_RETURN,
    60     /*  14 */   SDL_SCANCODE_UNKNOWN,
    61     /*  15 */   SDL_SCANCODE_UNKNOWN,
    62     /*  16 */   SDL_SCANCODE_LSHIFT,
    63     /*  17 */   SDL_SCANCODE_LCTRL,
    64     /*  18 */   SDL_SCANCODE_LALT,
    65     /*  19 */   SDL_SCANCODE_PAUSE,
    66     /*  20 */   SDL_SCANCODE_CAPSLOCK,
    67     /*  21 */   SDL_SCANCODE_UNKNOWN,
    68     /*  22 */   SDL_SCANCODE_UNKNOWN,
    69     /*  23 */   SDL_SCANCODE_UNKNOWN,
    70     /*  24 */   SDL_SCANCODE_UNKNOWN,
    71     /*  25 */   SDL_SCANCODE_UNKNOWN,
    72     /*  26 */   SDL_SCANCODE_UNKNOWN,
    73     /*  27 */   SDL_SCANCODE_ESCAPE,
    74     /*  28 */   SDL_SCANCODE_UNKNOWN,
    75     /*  29 */   SDL_SCANCODE_UNKNOWN,
    76     /*  30 */   SDL_SCANCODE_UNKNOWN,
    77     /*  31 */   SDL_SCANCODE_UNKNOWN,
    78     /*  32 */   SDL_SCANCODE_SPACE,
    79     /*  33 */   SDL_SCANCODE_PAGEUP,
    80     /*  34 */   SDL_SCANCODE_PAGEDOWN,
    81     /*  35 */   SDL_SCANCODE_END,
    82     /*  36 */   SDL_SCANCODE_HOME,
    83     /*  37 */   SDL_SCANCODE_LEFT,
    84     /*  38 */   SDL_SCANCODE_UP,
    85     /*  39 */   SDL_SCANCODE_RIGHT,
    86     /*  40 */   SDL_SCANCODE_DOWN,
    87     /*  41 */   SDL_SCANCODE_UNKNOWN,
    88     /*  42 */   SDL_SCANCODE_UNKNOWN,
    89     /*  43 */   SDL_SCANCODE_UNKNOWN,
    90     /*  44 */   SDL_SCANCODE_UNKNOWN,
    91     /*  45 */   SDL_SCANCODE_INSERT,
    92     /*  46 */   SDL_SCANCODE_DELETE,
    93     /*  47 */   SDL_SCANCODE_UNKNOWN,
    94     /*  48 */   SDL_SCANCODE_0,
    95     /*  49 */   SDL_SCANCODE_1,
    96     /*  50 */   SDL_SCANCODE_2,
    97     /*  51 */   SDL_SCANCODE_3,
    98     /*  52 */   SDL_SCANCODE_4,
    99     /*  53 */   SDL_SCANCODE_5,
   100     /*  54 */   SDL_SCANCODE_6,
   101     /*  55 */   SDL_SCANCODE_7,
   102     /*  56 */   SDL_SCANCODE_8,
   103     /*  57 */   SDL_SCANCODE_9,
   104     /*  58 */   SDL_SCANCODE_UNKNOWN,
   105     /*  59 */   SDL_SCANCODE_SEMICOLON,
   106     /*  60 */   SDL_SCANCODE_UNKNOWN,
   107     /*  61 */   SDL_SCANCODE_EQUALS,
   108     /*  62 */   SDL_SCANCODE_UNKNOWN,
   109     /*  63 */   SDL_SCANCODE_UNKNOWN,
   110     /*  64 */   SDL_SCANCODE_UNKNOWN,
   111     /*  65 */   SDL_SCANCODE_A,
   112     /*  66 */   SDL_SCANCODE_B,
   113     /*  67 */   SDL_SCANCODE_C,
   114     /*  68 */   SDL_SCANCODE_D,
   115     /*  69 */   SDL_SCANCODE_E,
   116     /*  70 */   SDL_SCANCODE_F,
   117     /*  71 */   SDL_SCANCODE_G,
   118     /*  72 */   SDL_SCANCODE_H,
   119     /*  73 */   SDL_SCANCODE_I,
   120     /*  74 */   SDL_SCANCODE_J,
   121     /*  75 */   SDL_SCANCODE_K,
   122     /*  76 */   SDL_SCANCODE_L,
   123     /*  77 */   SDL_SCANCODE_M,
   124     /*  78 */   SDL_SCANCODE_N,
   125     /*  79 */   SDL_SCANCODE_O,
   126     /*  80 */   SDL_SCANCODE_P,
   127     /*  81 */   SDL_SCANCODE_Q,
   128     /*  82 */   SDL_SCANCODE_R,
   129     /*  83 */   SDL_SCANCODE_S,
   130     /*  84 */   SDL_SCANCODE_T,
   131     /*  85 */   SDL_SCANCODE_U,
   132     /*  86 */   SDL_SCANCODE_V,
   133     /*  87 */   SDL_SCANCODE_W,
   134     /*  88 */   SDL_SCANCODE_X,
   135     /*  89 */   SDL_SCANCODE_Y,
   136     /*  90 */   SDL_SCANCODE_Z,
   137     /*  91 */   SDL_SCANCODE_LGUI,
   138     /*  92 */   SDL_SCANCODE_UNKNOWN,
   139     /*  93 */   SDL_SCANCODE_APPLICATION,
   140     /*  94 */   SDL_SCANCODE_UNKNOWN,
   141     /*  95 */   SDL_SCANCODE_UNKNOWN,
   142     /*  96 */   SDL_SCANCODE_KP_0,
   143     /*  97 */   SDL_SCANCODE_KP_1,
   144     /*  98 */   SDL_SCANCODE_KP_2,
   145     /*  99 */   SDL_SCANCODE_KP_3,
   146     /* 100 */   SDL_SCANCODE_KP_4,
   147     /* 101 */   SDL_SCANCODE_KP_5,
   148     /* 102 */   SDL_SCANCODE_KP_6,
   149     /* 103 */   SDL_SCANCODE_KP_7,
   150     /* 104 */   SDL_SCANCODE_KP_8,
   151     /* 105 */   SDL_SCANCODE_KP_9,
   152     /* 106 */   SDL_SCANCODE_KP_MULTIPLY,
   153     /* 107 */   SDL_SCANCODE_KP_PLUS,
   154     /* 108 */   SDL_SCANCODE_UNKNOWN,
   155     /* 109 */   SDL_SCANCODE_KP_MINUS,
   156     /* 110 */   SDL_SCANCODE_KP_PERIOD,
   157     /* 111 */   SDL_SCANCODE_KP_DIVIDE,
   158     /* 112 */   SDL_SCANCODE_F1,
   159     /* 113 */   SDL_SCANCODE_F2,
   160     /* 114 */   SDL_SCANCODE_F3,
   161     /* 115 */   SDL_SCANCODE_F4,
   162     /* 116 */   SDL_SCANCODE_F5,
   163     /* 117 */   SDL_SCANCODE_F6,
   164     /* 118 */   SDL_SCANCODE_F7,
   165     /* 119 */   SDL_SCANCODE_F8,
   166     /* 120 */   SDL_SCANCODE_F9,
   167     /* 121 */   SDL_SCANCODE_F10,
   168     /* 122 */   SDL_SCANCODE_F11,
   169     /* 123 */   SDL_SCANCODE_F12,
   170     /* 124 */   SDL_SCANCODE_F13,
   171     /* 125 */   SDL_SCANCODE_F14,
   172     /* 126 */   SDL_SCANCODE_F15,
   173     /* 127 */   SDL_SCANCODE_F16,
   174     /* 128 */   SDL_SCANCODE_F17,
   175     /* 129 */   SDL_SCANCODE_F18,
   176     /* 130 */   SDL_SCANCODE_F19,
   177     /* 131 */   SDL_SCANCODE_F20,
   178     /* 132 */   SDL_SCANCODE_F21,
   179     /* 133 */   SDL_SCANCODE_F22,
   180     /* 134 */   SDL_SCANCODE_F23,
   181     /* 135 */   SDL_SCANCODE_F24,
   182     /* 136 */   SDL_SCANCODE_UNKNOWN,
   183     /* 137 */   SDL_SCANCODE_UNKNOWN,
   184     /* 138 */   SDL_SCANCODE_UNKNOWN,
   185     /* 139 */   SDL_SCANCODE_UNKNOWN,
   186     /* 140 */   SDL_SCANCODE_UNKNOWN,
   187     /* 141 */   SDL_SCANCODE_UNKNOWN,
   188     /* 142 */   SDL_SCANCODE_UNKNOWN,
   189     /* 143 */   SDL_SCANCODE_UNKNOWN,
   190     /* 144 */   SDL_SCANCODE_NUMLOCKCLEAR,
   191     /* 145 */   SDL_SCANCODE_SCROLLLOCK,
   192     /* 146 */   SDL_SCANCODE_UNKNOWN,
   193     /* 147 */   SDL_SCANCODE_UNKNOWN,
   194     /* 148 */   SDL_SCANCODE_UNKNOWN,
   195     /* 149 */   SDL_SCANCODE_UNKNOWN,
   196     /* 150 */   SDL_SCANCODE_UNKNOWN,
   197     /* 151 */   SDL_SCANCODE_UNKNOWN,
   198     /* 152 */   SDL_SCANCODE_UNKNOWN,
   199     /* 153 */   SDL_SCANCODE_UNKNOWN,
   200     /* 154 */   SDL_SCANCODE_UNKNOWN,
   201     /* 155 */   SDL_SCANCODE_UNKNOWN,
   202     /* 156 */   SDL_SCANCODE_UNKNOWN,
   203     /* 157 */   SDL_SCANCODE_UNKNOWN,
   204     /* 158 */   SDL_SCANCODE_UNKNOWN,
   205     /* 159 */   SDL_SCANCODE_UNKNOWN,
   206     /* 160 */   SDL_SCANCODE_UNKNOWN,
   207     /* 161 */   SDL_SCANCODE_UNKNOWN,
   208     /* 162 */   SDL_SCANCODE_UNKNOWN,
   209     /* 163 */   SDL_SCANCODE_UNKNOWN,
   210     /* 164 */   SDL_SCANCODE_UNKNOWN,
   211     /* 165 */   SDL_SCANCODE_UNKNOWN,
   212     /* 166 */   SDL_SCANCODE_UNKNOWN,
   213     /* 167 */   SDL_SCANCODE_UNKNOWN,
   214     /* 168 */   SDL_SCANCODE_UNKNOWN,
   215     /* 169 */   SDL_SCANCODE_UNKNOWN,
   216     /* 170 */   SDL_SCANCODE_UNKNOWN,
   217     /* 171 */   SDL_SCANCODE_UNKNOWN,
   218     /* 172 */   SDL_SCANCODE_UNKNOWN,
   219     /* 173 */   SDL_SCANCODE_MINUS, /*FX*/
   220     /* 174 */   SDL_SCANCODE_VOLUMEDOWN, /*IE, Chrome*/
   221     /* 175 */   SDL_SCANCODE_VOLUMEUP, /*IE, Chrome*/
   222     /* 176 */   SDL_SCANCODE_AUDIONEXT, /*IE, Chrome*/
   223     /* 177 */   SDL_SCANCODE_AUDIOPREV, /*IE, Chrome*/
   224     /* 178 */   SDL_SCANCODE_UNKNOWN,
   225     /* 179 */   SDL_SCANCODE_AUDIOPLAY, /*IE, Chrome*/
   226     /* 180 */   SDL_SCANCODE_UNKNOWN,
   227     /* 181 */   SDL_SCANCODE_AUDIOMUTE, /*FX*/
   228     /* 182 */   SDL_SCANCODE_VOLUMEDOWN, /*FX*/
   229     /* 183 */   SDL_SCANCODE_VOLUMEUP, /*FX*/
   230     /* 184 */   SDL_SCANCODE_UNKNOWN,
   231     /* 185 */   SDL_SCANCODE_UNKNOWN,
   232     /* 186 */   SDL_SCANCODE_SEMICOLON, /*IE, Chrome, D3E legacy*/
   233     /* 187 */   SDL_SCANCODE_EQUALS, /*IE, Chrome, D3E legacy*/
   234     /* 188 */   SDL_SCANCODE_COMMA,
   235     /* 189 */   SDL_SCANCODE_MINUS, /*IE, Chrome, D3E legacy*/
   236     /* 190 */   SDL_SCANCODE_PERIOD,
   237     /* 191 */   SDL_SCANCODE_SLASH,
   238     /* 192 */   SDL_SCANCODE_GRAVE, /*FX, D3E legacy (SDL_SCANCODE_APOSTROPHE in IE/Chrome)*/
   239     /* 193 */   SDL_SCANCODE_UNKNOWN,
   240     /* 194 */   SDL_SCANCODE_UNKNOWN,
   241     /* 195 */   SDL_SCANCODE_UNKNOWN,
   242     /* 196 */   SDL_SCANCODE_UNKNOWN,
   243     /* 197 */   SDL_SCANCODE_UNKNOWN,
   244     /* 198 */   SDL_SCANCODE_UNKNOWN,
   245     /* 199 */   SDL_SCANCODE_UNKNOWN,
   246     /* 200 */   SDL_SCANCODE_UNKNOWN,
   247     /* 201 */   SDL_SCANCODE_UNKNOWN,
   248     /* 202 */   SDL_SCANCODE_UNKNOWN,
   249     /* 203 */   SDL_SCANCODE_UNKNOWN,
   250     /* 204 */   SDL_SCANCODE_UNKNOWN,
   251     /* 205 */   SDL_SCANCODE_UNKNOWN,
   252     /* 206 */   SDL_SCANCODE_UNKNOWN,
   253     /* 207 */   SDL_SCANCODE_UNKNOWN,
   254     /* 208 */   SDL_SCANCODE_UNKNOWN,
   255     /* 209 */   SDL_SCANCODE_UNKNOWN,
   256     /* 210 */   SDL_SCANCODE_UNKNOWN,
   257     /* 211 */   SDL_SCANCODE_UNKNOWN,
   258     /* 212 */   SDL_SCANCODE_UNKNOWN,
   259     /* 213 */   SDL_SCANCODE_UNKNOWN,
   260     /* 214 */   SDL_SCANCODE_UNKNOWN,
   261     /* 215 */   SDL_SCANCODE_UNKNOWN,
   262     /* 216 */   SDL_SCANCODE_UNKNOWN,
   263     /* 217 */   SDL_SCANCODE_UNKNOWN,
   264     /* 218 */   SDL_SCANCODE_UNKNOWN,
   265     /* 219 */   SDL_SCANCODE_LEFTBRACKET,
   266     /* 220 */   SDL_SCANCODE_BACKSLASH,
   267     /* 221 */   SDL_SCANCODE_RIGHTBRACKET,
   268     /* 222 */   SDL_SCANCODE_APOSTROPHE, /*FX, D3E legacy*/
   269 };
   270 
   271 
   272 /* "borrowed" from SDL_windowsevents.c */
   273 static int
   274 Emscripten_ConvertUTF32toUTF8(Uint32 codepoint, char * text)
   275 {
   276     if (codepoint <= 0x7F) {
   277         text[0] = (char) codepoint;
   278         text[1] = '\0';
   279     } else if (codepoint <= 0x7FF) {
   280         text[0] = 0xC0 | (char) ((codepoint >> 6) & 0x1F);
   281         text[1] = 0x80 | (char) (codepoint & 0x3F);
   282         text[2] = '\0';
   283     } else if (codepoint <= 0xFFFF) {
   284         text[0] = 0xE0 | (char) ((codepoint >> 12) & 0x0F);
   285         text[1] = 0x80 | (char) ((codepoint >> 6) & 0x3F);
   286         text[2] = 0x80 | (char) (codepoint & 0x3F);
   287         text[3] = '\0';
   288     } else if (codepoint <= 0x10FFFF) {
   289         text[0] = 0xF0 | (char) ((codepoint >> 18) & 0x0F);
   290         text[1] = 0x80 | (char) ((codepoint >> 12) & 0x3F);
   291         text[2] = 0x80 | (char) ((codepoint >> 6) & 0x3F);
   292         text[3] = 0x80 | (char) (codepoint & 0x3F);
   293         text[4] = '\0';
   294     } else {
   295         return SDL_FALSE;
   296     }
   297     return SDL_TRUE;
   298 }
   299 
   300 static EM_BOOL
   301 Emscripten_HandlePointerLockChange(int eventType, const EmscriptenPointerlockChangeEvent *changeEvent, void *userData)
   302 {
   303     SDL_WindowData *window_data = (SDL_WindowData *) userData;
   304     /* keep track of lock losses, so we can regrab if/when appropriate. */
   305     window_data->has_pointer_lock = changeEvent->isActive;
   306     return 0;
   307 }
   308 
   309 
   310 static EM_BOOL
   311 Emscripten_HandleMouseMove(int eventType, const EmscriptenMouseEvent *mouseEvent, void *userData)
   312 {
   313     SDL_WindowData *window_data = userData;
   314     const int isPointerLocked = window_data->has_pointer_lock;
   315     int mx, my;
   316     static double residualx = 0, residualy = 0;
   317 
   318     /* rescale (in case canvas is being scaled)*/
   319     double client_w, client_h, xscale, yscale;
   320     emscripten_get_element_css_size(NULL, &client_w, &client_h);
   321     xscale = window_data->window->w / client_w;
   322     yscale = window_data->window->h / client_h;
   323 
   324     if (isPointerLocked) {
   325         residualx += mouseEvent->movementX * xscale;
   326         residualy += mouseEvent->movementY * yscale;
   327         /* Let slow sub-pixel motion accumulate. Don't lose it. */
   328         mx = residualx;
   329         residualx -= mx;
   330         my = residualy;
   331         residualy -= my;
   332     } else {
   333         mx = mouseEvent->canvasX * xscale;
   334         my = mouseEvent->canvasY * yscale;
   335     }
   336 
   337     SDL_SendMouseMotion(window_data->window, 0, isPointerLocked, mx, my);
   338     return 0;
   339 }
   340 
   341 static EM_BOOL
   342 Emscripten_HandleMouseButton(int eventType, const EmscriptenMouseEvent *mouseEvent, void *userData)
   343 {
   344     SDL_WindowData *window_data = userData;
   345     Uint8 sdl_button;
   346     Uint8 sdl_button_state;
   347     SDL_EventType sdl_event_type;
   348 
   349     switch (mouseEvent->button) {
   350         case 0:
   351             sdl_button = SDL_BUTTON_LEFT;
   352             break;
   353         case 1:
   354             sdl_button = SDL_BUTTON_MIDDLE;
   355             break;
   356         case 2:
   357             sdl_button = SDL_BUTTON_RIGHT;
   358             break;
   359         default:
   360             return 0;
   361     }
   362 
   363     if (eventType == EMSCRIPTEN_EVENT_MOUSEDOWN) {
   364         if (SDL_GetMouse()->relative_mode && !window_data->has_pointer_lock) {
   365             emscripten_request_pointerlock(NULL, 0);  /* try to regrab lost pointer lock. */
   366         }
   367         sdl_button_state = SDL_PRESSED;
   368         sdl_event_type = SDL_MOUSEBUTTONDOWN;
   369     } else {
   370         sdl_button_state = SDL_RELEASED;
   371         sdl_event_type = SDL_MOUSEBUTTONUP;
   372     }
   373     SDL_SendMouseButton(window_data->window, 0, sdl_button_state, sdl_button);
   374     return SDL_GetEventState(sdl_event_type) == SDL_ENABLE;
   375 }
   376 
   377 static EM_BOOL
   378 Emscripten_HandleMouseFocus(int eventType, const EmscriptenMouseEvent *mouseEvent, void *userData)
   379 {
   380     SDL_WindowData *window_data = userData;
   381 
   382     int mx = mouseEvent->canvasX, my = mouseEvent->canvasY;
   383     const int isPointerLocked = window_data->has_pointer_lock;
   384 
   385     if (!isPointerLocked) {
   386         /* rescale (in case canvas is being scaled)*/
   387         double client_w, client_h;
   388         emscripten_get_element_css_size(NULL, &client_w, &client_h);
   389 
   390         mx = mx * (window_data->window->w / client_w);
   391         my = my * (window_data->window->h / client_h);
   392         SDL_SendMouseMotion(window_data->window, 0, isPointerLocked, mx, my);
   393     }
   394 
   395     SDL_SetMouseFocus(eventType == EMSCRIPTEN_EVENT_MOUSEENTER ? window_data->window : NULL);
   396     return SDL_GetEventState(SDL_WINDOWEVENT) == SDL_ENABLE;
   397 }
   398 
   399 static EM_BOOL
   400 Emscripten_HandleWheel(int eventType, const EmscriptenWheelEvent *wheelEvent, void *userData)
   401 {
   402     SDL_WindowData *window_data = userData;
   403     SDL_SendMouseWheel(window_data->window, 0, (float)wheelEvent->deltaX, (float)-wheelEvent->deltaY, SDL_MOUSEWHEEL_NORMAL);
   404     return SDL_GetEventState(SDL_MOUSEWHEEL) == SDL_ENABLE;
   405 }
   406 
   407 static EM_BOOL
   408 Emscripten_HandleFocus(int eventType, const EmscriptenFocusEvent *wheelEvent, void *userData)
   409 {
   410     SDL_WindowData *window_data = userData;
   411     /* If the user switches away while keys are pressed (such as
   412      * via Alt+Tab), key release events won't be received. */
   413     if (eventType == EMSCRIPTEN_EVENT_BLUR) {
   414         SDL_ResetKeyboard();
   415     }
   416 
   417 
   418     SDL_SendWindowEvent(window_data->window, eventType == EMSCRIPTEN_EVENT_FOCUS ? SDL_WINDOWEVENT_FOCUS_GAINED : SDL_WINDOWEVENT_FOCUS_LOST, 0, 0);
   419     return SDL_GetEventState(SDL_WINDOWEVENT) == SDL_ENABLE;
   420 }
   421 
   422 static EM_BOOL
   423 Emscripten_HandleTouch(int eventType, const EmscriptenTouchEvent *touchEvent, void *userData)
   424 {
   425     SDL_WindowData *window_data = userData;
   426     int i;
   427     double client_w, client_h;
   428     int preventDefault = 0;
   429 
   430     SDL_TouchID deviceId = 1;
   431     if (SDL_AddTouch(deviceId, SDL_TOUCH_DEVICE_DIRECT, "") < 0) {
   432          return 0;
   433     }
   434 
   435     emscripten_get_element_css_size(NULL, &client_w, &client_h);
   436 
   437     for (i = 0; i < touchEvent->numTouches; i++) {
   438         SDL_FingerID id;
   439         float x, y;
   440         int mx, my;
   441 
   442         if (!touchEvent->touches[i].isChanged)
   443             continue;
   444 
   445         id = touchEvent->touches[i].identifier;
   446         x = touchEvent->touches[i].canvasX / client_w;
   447         y = touchEvent->touches[i].canvasY / client_h;
   448 
   449         mx = x * window_data->window->w;
   450         my = y * window_data->window->h;
   451 
   452         if (eventType == EMSCRIPTEN_EVENT_TOUCHSTART) {
   453             if (!window_data->finger_touching) {
   454                 window_data->finger_touching = SDL_TRUE;
   455                 window_data->first_finger = id;
   456                 SDL_SendMouseMotion(window_data->window, SDL_TOUCH_MOUSEID, 0, mx, my);
   457                 SDL_SendMouseButton(window_data->window, SDL_TOUCH_MOUSEID, SDL_PRESSED, SDL_BUTTON_LEFT);
   458             }
   459             SDL_SendTouch(deviceId, id, SDL_TRUE, x, y, 1.0f);
   460 
   461             if (!preventDefault && SDL_GetEventState(SDL_FINGERDOWN) == SDL_ENABLE) {
   462                 preventDefault = 1;
   463             }
   464         } else if (eventType == EMSCRIPTEN_EVENT_TOUCHMOVE) {
   465             if ((window_data->finger_touching) && (window_data->first_finger == id)) {
   466                 SDL_SendMouseMotion(window_data->window, SDL_TOUCH_MOUSEID, 0, mx, my);
   467             }
   468             SDL_SendTouchMotion(deviceId, id, x, y, 1.0f);
   469 
   470             if (!preventDefault && SDL_GetEventState(SDL_FINGERMOTION) == SDL_ENABLE) {
   471                 preventDefault = 1;
   472             }
   473         } else {
   474             if ((window_data->finger_touching) && (window_data->first_finger == id)) {
   475                 SDL_SendMouseButton(window_data->window, SDL_TOUCH_MOUSEID, SDL_RELEASED, SDL_BUTTON_LEFT);
   476                 window_data->finger_touching = SDL_FALSE;
   477             }
   478             SDL_SendTouch(deviceId, id, SDL_FALSE, x, y, 1.0f);
   479 
   480             if (!preventDefault && SDL_GetEventState(SDL_FINGERUP) == SDL_ENABLE) {
   481                 preventDefault = 1;
   482             }
   483         }
   484     }
   485 
   486     return preventDefault;
   487 }
   488 
   489 static EM_BOOL
   490 Emscripten_HandleKey(int eventType, const EmscriptenKeyboardEvent *keyEvent, void *userData)
   491 {
   492     Uint32 scancode;
   493     SDL_bool prevent_default;
   494     SDL_bool is_nav_key;
   495 
   496     /* .keyCode is deprecated, but still the most reliable way to get keys */
   497     if (keyEvent->keyCode < SDL_arraysize(emscripten_scancode_table)) {
   498         scancode = emscripten_scancode_table[keyEvent->keyCode];
   499 
   500         if (scancode != SDL_SCANCODE_UNKNOWN) {
   501 
   502             if (keyEvent->location == DOM_KEY_LOCATION_RIGHT) {
   503                 switch (scancode) {
   504                     case SDL_SCANCODE_LSHIFT:
   505                         scancode = SDL_SCANCODE_RSHIFT;
   506                         break;
   507                     case SDL_SCANCODE_LCTRL:
   508                         scancode = SDL_SCANCODE_RCTRL;
   509                         break;
   510                     case SDL_SCANCODE_LALT:
   511                         scancode = SDL_SCANCODE_RALT;
   512                         break;
   513                     case SDL_SCANCODE_LGUI:
   514                         scancode = SDL_SCANCODE_RGUI;
   515                         break;
   516                 }
   517             }
   518             SDL_SendKeyboardKey(eventType == EMSCRIPTEN_EVENT_KEYDOWN ? SDL_PRESSED : SDL_RELEASED, scancode);
   519         }
   520     }
   521 
   522     prevent_default = SDL_GetEventState(eventType == EMSCRIPTEN_EVENT_KEYDOWN ? SDL_KEYDOWN : SDL_KEYUP) == SDL_ENABLE;
   523 
   524     /* if TEXTINPUT events are enabled we can't prevent keydown or we won't get keypress
   525      * we need to ALWAYS prevent backspace and tab otherwise chrome takes action and does bad navigation UX
   526      */
   527     is_nav_key = keyEvent->keyCode == 8 /* backspace */ ||
   528                  keyEvent->keyCode == 9 /* tab */ ||
   529                  keyEvent->keyCode == 37 /* left */ ||
   530                  keyEvent->keyCode == 38 /* up */ ||
   531                  keyEvent->keyCode == 39 /* right */ ||
   532                  keyEvent->keyCode == 40 /* down */;
   533 
   534     if (eventType == EMSCRIPTEN_EVENT_KEYDOWN && SDL_GetEventState(SDL_TEXTINPUT) == SDL_ENABLE && !is_nav_key)
   535         prevent_default = SDL_FALSE;
   536 
   537     return prevent_default;
   538 }
   539 
   540 static EM_BOOL
   541 Emscripten_HandleKeyPress(int eventType, const EmscriptenKeyboardEvent *keyEvent, void *userData)
   542 {
   543     char text[5];
   544     if (Emscripten_ConvertUTF32toUTF8(keyEvent->charCode, text)) {
   545         SDL_SendKeyboardText(text);
   546     }
   547     return SDL_GetEventState(SDL_TEXTINPUT) == SDL_ENABLE;
   548 }
   549 
   550 static EM_BOOL
   551 Emscripten_HandleFullscreenChange(int eventType, const EmscriptenFullscreenChangeEvent *fullscreenChangeEvent, void *userData)
   552 {
   553     SDL_WindowData *window_data = userData;
   554     SDL_VideoDisplay *display;
   555 
   556     if(fullscreenChangeEvent->isFullscreen)
   557     {
   558         window_data->window->flags |= window_data->requested_fullscreen_mode;
   559 
   560         window_data->requested_fullscreen_mode = 0;
   561 
   562         if(!window_data->requested_fullscreen_mode)
   563             window_data->window->flags |= SDL_WINDOW_FULLSCREEN; /*we didn't reqest fullscreen*/
   564     }
   565     else
   566     {
   567         window_data->window->flags &= ~FULLSCREEN_MASK;
   568 
   569         /* reset fullscreen window if the browser left fullscreen */
   570         display = SDL_GetDisplayForWindow(window_data->window);
   571 
   572         if (display->fullscreen_window == window_data->window) {
   573             display->fullscreen_window = NULL;
   574         }
   575     }
   576 
   577     return 0;
   578 }
   579 
   580 static EM_BOOL
   581 Emscripten_HandleResize(int eventType, const EmscriptenUiEvent *uiEvent, void *userData)
   582 {
   583     SDL_WindowData *window_data = userData;
   584 
   585     /* update pixel ratio */
   586     if (window_data->window->flags & SDL_WINDOW_ALLOW_HIGHDPI) {
   587         window_data->pixel_ratio = emscripten_get_device_pixel_ratio();
   588     }
   589 
   590     if(!(window_data->window->flags & FULLSCREEN_MASK))
   591     {
   592         /* this will only work if the canvas size is set through css */
   593         if(window_data->window->flags & SDL_WINDOW_RESIZABLE)
   594         {
   595             double w = window_data->window->w;
   596             double h = window_data->window->h;
   597 
   598             if(window_data->external_size) {
   599                 emscripten_get_element_css_size(NULL, &w, &h);
   600             }
   601 
   602             emscripten_set_canvas_size(w * window_data->pixel_ratio, h * window_data->pixel_ratio);
   603 
   604             /* set_canvas_size unsets this */
   605             if (!window_data->external_size && window_data->pixel_ratio != 1.0f) {
   606                 emscripten_set_element_css_size(NULL, w, h);
   607             }
   608 
   609             SDL_SendWindowEvent(window_data->window, SDL_WINDOWEVENT_RESIZED, w, h);
   610         }
   611     }
   612 
   613     return 0;
   614 }
   615 
   616 EM_BOOL
   617 Emscripten_HandleCanvasResize(int eventType, const void *reserved, void *userData)
   618 {
   619     /*this is used during fullscreen changes*/
   620     SDL_WindowData *window_data = userData;
   621 
   622     if(window_data->fullscreen_resize)
   623     {
   624         double css_w, css_h;
   625         emscripten_get_element_css_size(NULL, &css_w, &css_h);
   626         SDL_SendWindowEvent(window_data->window, SDL_WINDOWEVENT_RESIZED, css_w, css_h);
   627     }
   628 
   629     return 0;
   630 }
   631 
   632 static EM_BOOL
   633 Emscripten_HandleVisibilityChange(int eventType, const EmscriptenVisibilityChangeEvent *visEvent, void *userData)
   634 {
   635     SDL_WindowData *window_data = userData;
   636     SDL_SendWindowEvent(window_data->window, visEvent->hidden ? SDL_WINDOWEVENT_HIDDEN : SDL_WINDOWEVENT_SHOWN, 0, 0);
   637     return 0;
   638 }
   639 
   640 void
   641 Emscripten_RegisterEventHandlers(SDL_WindowData *data)
   642 {
   643     const char *keyElement;
   644 
   645     /* There is only one window and that window is the canvas */
   646     emscripten_set_mousemove_callback("#canvas", data, 0, Emscripten_HandleMouseMove);
   647 
   648     emscripten_set_mousedown_callback("#canvas", data, 0, Emscripten_HandleMouseButton);
   649     emscripten_set_mouseup_callback("#document", data, 0, Emscripten_HandleMouseButton);
   650 
   651     emscripten_set_mouseenter_callback("#canvas", data, 0, Emscripten_HandleMouseFocus);
   652     emscripten_set_mouseleave_callback("#canvas", data, 0, Emscripten_HandleMouseFocus);
   653 
   654     emscripten_set_wheel_callback("#canvas", data, 0, Emscripten_HandleWheel);
   655 
   656     emscripten_set_focus_callback("#window", data, 0, Emscripten_HandleFocus);
   657     emscripten_set_blur_callback("#window", data, 0, Emscripten_HandleFocus);
   658 
   659     emscripten_set_touchstart_callback("#canvas", data, 0, Emscripten_HandleTouch);
   660     emscripten_set_touchend_callback("#canvas", data, 0, Emscripten_HandleTouch);
   661     emscripten_set_touchmove_callback("#canvas", data, 0, Emscripten_HandleTouch);
   662     emscripten_set_touchcancel_callback("#canvas", data, 0, Emscripten_HandleTouch);
   663 
   664     emscripten_set_pointerlockchange_callback("#document", data, 0, Emscripten_HandlePointerLockChange);
   665 
   666     /* Keyboard events are awkward */
   667     keyElement = SDL_GetHint(SDL_HINT_EMSCRIPTEN_KEYBOARD_ELEMENT);
   668     if (!keyElement) keyElement = "#window";
   669 
   670     emscripten_set_keydown_callback(keyElement, data, 0, Emscripten_HandleKey);
   671     emscripten_set_keyup_callback(keyElement, data, 0, Emscripten_HandleKey);
   672     emscripten_set_keypress_callback(keyElement, data, 0, Emscripten_HandleKeyPress);
   673 
   674     emscripten_set_fullscreenchange_callback("#document", data, 0, Emscripten_HandleFullscreenChange);
   675 
   676     emscripten_set_resize_callback("#window", data, 0, Emscripten_HandleResize);
   677 
   678     emscripten_set_visibilitychange_callback(data, 0, Emscripten_HandleVisibilityChange);
   679 }
   680 
   681 void
   682 Emscripten_UnregisterEventHandlers(SDL_WindowData *data)
   683 {
   684     const char *target;
   685 
   686     /* only works due to having one window */
   687     emscripten_set_mousemove_callback("#canvas", NULL, 0, NULL);
   688 
   689     emscripten_set_mousedown_callback("#canvas", NULL, 0, NULL);
   690     emscripten_set_mouseup_callback("#document", NULL, 0, NULL);
   691 
   692     emscripten_set_mouseenter_callback("#canvas", NULL, 0, NULL);
   693     emscripten_set_mouseleave_callback("#canvas", NULL, 0, NULL);
   694 
   695     emscripten_set_wheel_callback("#canvas", NULL, 0, NULL);
   696 
   697     emscripten_set_focus_callback("#window", NULL, 0, NULL);
   698     emscripten_set_blur_callback("#window", NULL, 0, NULL);
   699 
   700     emscripten_set_touchstart_callback("#canvas", NULL, 0, NULL);
   701     emscripten_set_touchend_callback("#canvas", NULL, 0, NULL);
   702     emscripten_set_touchmove_callback("#canvas", NULL, 0, NULL);
   703     emscripten_set_touchcancel_callback("#canvas", NULL, 0, NULL);
   704 
   705     emscripten_set_pointerlockchange_callback("#document", NULL, 0, NULL);
   706 
   707     target = SDL_GetHint(SDL_HINT_EMSCRIPTEN_KEYBOARD_ELEMENT);
   708     if (!target) {
   709         target = "#window";
   710     }
   711 
   712     emscripten_set_keydown_callback(target, NULL, 0, NULL);
   713     emscripten_set_keyup_callback(target, NULL, 0, NULL);
   714     emscripten_set_keypress_callback(target, NULL, 0, NULL);
   715 
   716     emscripten_set_fullscreenchange_callback("#document", NULL, 0, NULL);
   717 
   718     emscripten_set_resize_callback("#window", NULL, 0, NULL);
   719 
   720     emscripten_set_visibilitychange_callback(NULL, 0, NULL);
   721 }
   722 
   723 #endif /* SDL_VIDEO_DRIVER_EMSCRIPTEN */
   724 
   725 /* vi: set ts=4 sw=4 expandtab: */