src/video/emscripten/SDL_emscriptenevents.c
author Boris Gjenero <boris.gjenero@gmail.com>
Tue, 13 Sep 2016 00:03:49 -0700
changeset 10328 3e6cd603c977
parent 10327 47d840cce014
child 10330 6928ce726856
permissions -rw-r--r--
Unpress all keys on blur to avoid stuck keys
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2016 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_UNKNOWN,
   221     /* 175 */   SDL_SCANCODE_UNKNOWN,
   222     /* 176 */   SDL_SCANCODE_UNKNOWN,
   223     /* 177 */   SDL_SCANCODE_UNKNOWN,
   224     /* 178 */   SDL_SCANCODE_UNKNOWN,
   225     /* 179 */   SDL_SCANCODE_UNKNOWN,
   226     /* 180 */   SDL_SCANCODE_UNKNOWN,
   227     /* 181 */   SDL_SCANCODE_UNKNOWN,
   228     /* 182 */   SDL_SCANCODE_UNKNOWN,
   229     /* 183 */   SDL_SCANCODE_UNKNOWN,
   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 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 EM_BOOL
   301 Emscripten_HandleMouseMove(int eventType, const EmscriptenMouseEvent *mouseEvent, void *userData)
   302 {
   303     SDL_WindowData *window_data = userData;
   304     int mx, my;
   305     static double residualx = 0, residualy = 0;
   306     EmscriptenPointerlockChangeEvent pointerlock_status;
   307 
   308     /* rescale (in case canvas is being scaled)*/
   309     double client_w, client_h, xscale, yscale;
   310     emscripten_get_element_css_size(NULL, &client_w, &client_h);
   311     xscale = window_data->window->w / client_w;
   312     yscale = window_data->window->h / client_h;
   313 
   314     /* check for pointer lock */
   315     int isPointerLockSupported = emscripten_get_pointerlock_status(&pointerlock_status);
   316     int isPointerLocked = isPointerLockSupported == EMSCRIPTEN_RESULT_SUCCESS  ? pointerlock_status.isActive : SDL_FALSE;
   317 
   318     if (isPointerLocked) {
   319         residualx += mouseEvent->movementX * xscale;
   320         residualy += mouseEvent->movementY * yscale;
   321         /* Let slow sub-pixel motion accumulate. Don't lose it. */
   322         mx = residualx;
   323         residualx -= mx;
   324         my = residualy;
   325         residualy -= my;
   326     } else {
   327         mx = mouseEvent->canvasX * xscale;
   328         my = mouseEvent->canvasY * yscale;
   329     }
   330 
   331     SDL_SendMouseMotion(window_data->window, 0, isPointerLocked, mx, my);
   332     return 0;
   333 }
   334 
   335 EM_BOOL
   336 Emscripten_HandleMouseButton(int eventType, const EmscriptenMouseEvent *mouseEvent, void *userData)
   337 {
   338     SDL_WindowData *window_data = userData;
   339     uint32_t sdl_button;
   340     switch (mouseEvent->button) {
   341         case 0:
   342             sdl_button = SDL_BUTTON_LEFT;
   343             break;
   344         case 1:
   345             sdl_button = SDL_BUTTON_MIDDLE;
   346             break;
   347         case 2:
   348             sdl_button = SDL_BUTTON_RIGHT;
   349             break;
   350         default:
   351             return 0;
   352     }
   353     SDL_SendMouseButton(window_data->window, 0, eventType == EMSCRIPTEN_EVENT_MOUSEDOWN ? SDL_PRESSED : SDL_RELEASED, sdl_button);
   354     return 1;
   355 }
   356 
   357 EM_BOOL
   358 Emscripten_HandleMouseFocus(int eventType, const EmscriptenMouseEvent *mouseEvent, void *userData)
   359 {
   360     SDL_WindowData *window_data = userData;
   361 
   362     int mx = mouseEvent->canvasX, my = mouseEvent->canvasY;
   363     EmscriptenPointerlockChangeEvent pointerlock_status;
   364 
   365     /* check for pointer lock */
   366     int isPointerLockSupported = emscripten_get_pointerlock_status(&pointerlock_status);
   367     int isPointerLocked = isPointerLockSupported == EMSCRIPTEN_RESULT_SUCCESS  ? pointerlock_status.isActive : SDL_FALSE;
   368 
   369     if (!isPointerLocked) {
   370         /* rescale (in case canvas is being scaled)*/
   371         double client_w, client_h;
   372         emscripten_get_element_css_size(NULL, &client_w, &client_h);
   373 
   374         mx = mx * (window_data->window->w / client_w);
   375         my = my * (window_data->window->h / client_h);
   376         SDL_SendMouseMotion(window_data->window, 0, isPointerLocked, mx, my);
   377     }
   378 
   379     SDL_SetMouseFocus(eventType == EMSCRIPTEN_EVENT_MOUSEENTER ? window_data->window : NULL);
   380     return 1;
   381 }
   382 
   383 EM_BOOL
   384 Emscripten_HandleWheel(int eventType, const EmscriptenWheelEvent *wheelEvent, void *userData)
   385 {
   386     SDL_WindowData *window_data = userData;
   387     SDL_SendMouseWheel(window_data->window, 0, wheelEvent->deltaX, -wheelEvent->deltaY, SDL_MOUSEWHEEL_NORMAL);
   388     return 1;
   389 }
   390 
   391 EM_BOOL
   392 Emscripten_HandleFocus(int eventType, const EmscriptenFocusEvent *wheelEvent, void *userData)
   393 {
   394     SDL_WindowData *window_data = userData;
   395     /* If the user switches away while keys are pressed (such as
   396      * via Alt+Tab), key release events won't be received. */
   397     if (eventType == EMSCRIPTEN_EVENT_BLUR) {
   398         SDL_ResetKeyboard();
   399     }
   400     SDL_SendWindowEvent(window_data->window, eventType == EMSCRIPTEN_EVENT_FOCUS ? SDL_WINDOWEVENT_FOCUS_GAINED : SDL_WINDOWEVENT_FOCUS_LOST, 0, 0);
   401     return 1;
   402 }
   403 
   404 EM_BOOL
   405 Emscripten_HandleTouch(int eventType, const EmscriptenTouchEvent *touchEvent, void *userData)
   406 {
   407     SDL_WindowData *window_data = userData;
   408     int i;
   409     double client_w, client_h;
   410 
   411     SDL_TouchID deviceId = 1;
   412     if (SDL_AddTouch(deviceId, "") < 0) {
   413          return 0;
   414     }
   415 
   416     emscripten_get_element_css_size(NULL, &client_w, &client_h);
   417 
   418     for (i = 0; i < touchEvent->numTouches; i++) {
   419         SDL_FingerID id;
   420         float x, y;
   421 
   422         if (!touchEvent->touches[i].isChanged)
   423             continue;
   424 
   425         id = touchEvent->touches[i].identifier;
   426         x = touchEvent->touches[i].canvasX / client_w;
   427         y = touchEvent->touches[i].canvasY / client_h;
   428 
   429         if (eventType == EMSCRIPTEN_EVENT_TOUCHSTART) {
   430             if (!window_data->finger_touching) {
   431                 window_data->finger_touching = SDL_TRUE;
   432                 window_data->first_finger = id;
   433                 SDL_SendMouseMotion(window_data->window, SDL_TOUCH_MOUSEID, 0, x, y);
   434                 SDL_SendMouseButton(window_data->window, SDL_TOUCH_MOUSEID, SDL_PRESSED, SDL_BUTTON_LEFT);
   435             }
   436             SDL_SendTouch(deviceId, id, SDL_TRUE, x, y, 1.0f);
   437         } else if (eventType == EMSCRIPTEN_EVENT_TOUCHMOVE) {
   438             if ((window_data->finger_touching) && (window_data->first_finger == id)) {
   439                 SDL_SendMouseMotion(window_data->window, SDL_TOUCH_MOUSEID, 0, x, y);
   440             }
   441             SDL_SendTouchMotion(deviceId, id, x, y, 1.0f);
   442         } else {
   443             if ((window_data->finger_touching) && (window_data->first_finger == id)) {
   444                 SDL_SendMouseButton(window_data->window, SDL_TOUCH_MOUSEID, SDL_RELEASED, SDL_BUTTON_LEFT);
   445                 window_data->finger_touching = SDL_FALSE;
   446             }
   447             SDL_SendTouch(deviceId, id, SDL_FALSE, x, y, 1.0f);
   448         }
   449     }
   450 
   451 
   452     return 1;
   453 }
   454 
   455 EM_BOOL
   456 Emscripten_HandleKey(int eventType, const EmscriptenKeyboardEvent *keyEvent, void *userData)
   457 {
   458     Uint32 scancode;
   459 
   460     /* .keyCode is deprecated, but still the most reliable way to get keys */
   461     if (keyEvent->keyCode < SDL_arraysize(emscripten_scancode_table)) {
   462         scancode = emscripten_scancode_table[keyEvent->keyCode];
   463 
   464         if (scancode != SDL_SCANCODE_UNKNOWN) {
   465 
   466             if (keyEvent->location == DOM_KEY_LOCATION_RIGHT) {
   467                 switch (scancode) {
   468                     case SDL_SCANCODE_LSHIFT:
   469                         scancode = SDL_SCANCODE_RSHIFT;
   470                         break;
   471                     case SDL_SCANCODE_LCTRL:
   472                         scancode = SDL_SCANCODE_RCTRL;
   473                         break;
   474                     case SDL_SCANCODE_LALT:
   475                         scancode = SDL_SCANCODE_RALT;
   476                         break;
   477                     case SDL_SCANCODE_LGUI:
   478                         scancode = SDL_SCANCODE_RGUI;
   479                         break;
   480                 }
   481             }
   482             SDL_SendKeyboardKey(eventType == EMSCRIPTEN_EVENT_KEYDOWN ?
   483                                 SDL_PRESSED : SDL_RELEASED, scancode);
   484         }
   485     }
   486 
   487     /* if we prevent keydown, we won't get keypress
   488      * also we need to ALWAYS prevent backspace and tab otherwise chrome takes action and does bad navigation UX
   489      */
   490     return SDL_GetEventState(SDL_TEXTINPUT) != SDL_ENABLE || eventType != EMSCRIPTEN_EVENT_KEYDOWN
   491             || keyEvent->keyCode == 8 /* backspace */ || keyEvent->keyCode == 9 /* tab */;
   492 }
   493 
   494 EM_BOOL
   495 Emscripten_HandleKeyPress(int eventType, const EmscriptenKeyboardEvent *keyEvent, void *userData)
   496 {
   497     char text[5];
   498     if (Emscripten_ConvertUTF32toUTF8(keyEvent->charCode, text)) {
   499         SDL_SendKeyboardText(text);
   500     }
   501     return 1;
   502 }
   503 
   504 EM_BOOL
   505 Emscripten_HandleFullscreenChange(int eventType, const EmscriptenFullscreenChangeEvent *fullscreenChangeEvent, void *userData)
   506 {
   507     SDL_WindowData *window_data = userData;
   508     if(fullscreenChangeEvent->isFullscreen)
   509     {
   510         SDL_bool is_desktop_fullscreen;
   511         window_data->window->flags |= window_data->requested_fullscreen_mode;
   512 
   513         window_data->requested_fullscreen_mode = 0;
   514 
   515         if(!window_data->requested_fullscreen_mode)
   516             window_data->window->flags |= SDL_WINDOW_FULLSCREEN; /*we didn't reqest fullscreen*/
   517     }
   518     else
   519     {
   520         window_data->window->flags &= ~FULLSCREEN_MASK;
   521     }
   522 
   523     return 0;
   524 }
   525 
   526 EM_BOOL
   527 Emscripten_HandleResize(int eventType, const EmscriptenUiEvent *uiEvent, void *userData)
   528 {
   529     SDL_WindowData *window_data = userData;
   530     if(!(window_data->window->flags & FULLSCREEN_MASK))
   531     {
   532         /* this will only work if the canvas size is set through css */
   533         if(window_data->window->flags & SDL_WINDOW_RESIZABLE)
   534         {
   535             double w = window_data->window->w;
   536             double h = window_data->window->h;
   537 
   538             if(window_data->external_size) {
   539                 emscripten_get_element_css_size(NULL, &w, &h);
   540             }
   541 
   542             emscripten_set_canvas_size(w * window_data->pixel_ratio, h * window_data->pixel_ratio);
   543 
   544             /* set_canvas_size unsets this */
   545             if (!window_data->external_size && window_data->pixel_ratio != 1.0f) {
   546                 emscripten_set_element_css_size(NULL, w, h);
   547             }
   548 
   549             SDL_SendWindowEvent(window_data->window, SDL_WINDOWEVENT_RESIZED, w, h);
   550         }
   551     }
   552 
   553     return 0;
   554 }
   555 
   556 EM_BOOL
   557 Emscripten_HandleCanvasResize(int eventType, const void *reserved, void *userData)
   558 {
   559     /*this is used during fullscreen changes*/
   560     SDL_WindowData *window_data = userData;
   561 
   562     if(window_data->fullscreen_resize)
   563     {
   564         double css_w, css_h;
   565         emscripten_get_element_css_size(NULL, &css_w, &css_h);
   566         SDL_SendWindowEvent(window_data->window, SDL_WINDOWEVENT_RESIZED, css_w, css_h);
   567     }
   568 
   569     return 0;
   570 }
   571 
   572 EM_BOOL
   573 Emscripten_HandleVisibilityChange(int eventType, const EmscriptenVisibilityChangeEvent *visEvent, void *userData)
   574 {
   575     SDL_WindowData *window_data = userData;
   576     SDL_SendWindowEvent(window_data->window, visEvent->hidden ? SDL_WINDOWEVENT_HIDDEN : SDL_WINDOWEVENT_SHOWN, 0, 0);
   577     return 0;
   578 }
   579 
   580 void
   581 Emscripten_RegisterEventHandlers(SDL_WindowData *data)
   582 {
   583     /* There is only one window and that window is the canvas */
   584     emscripten_set_mousemove_callback("#canvas", data, 0, Emscripten_HandleMouseMove);
   585 
   586     emscripten_set_mousedown_callback("#canvas", data, 0, Emscripten_HandleMouseButton);
   587     emscripten_set_mouseup_callback("#document", data, 0, Emscripten_HandleMouseButton);
   588 
   589     emscripten_set_mouseenter_callback("#canvas", data, 0, Emscripten_HandleMouseFocus);
   590     emscripten_set_mouseleave_callback("#canvas", data, 0, Emscripten_HandleMouseFocus);
   591 
   592     emscripten_set_wheel_callback("#canvas", data, 0, Emscripten_HandleWheel);
   593 
   594     emscripten_set_focus_callback("#window", data, 0, Emscripten_HandleFocus);
   595     emscripten_set_blur_callback("#window", data, 0, Emscripten_HandleFocus);
   596 
   597     emscripten_set_touchstart_callback("#canvas", data, 0, Emscripten_HandleTouch);
   598     emscripten_set_touchend_callback("#canvas", data, 0, Emscripten_HandleTouch);
   599     emscripten_set_touchmove_callback("#canvas", data, 0, Emscripten_HandleTouch);
   600     emscripten_set_touchcancel_callback("#canvas", data, 0, Emscripten_HandleTouch);
   601 
   602     /* Keyboard events are awkward */
   603     const char *keyElement = SDL_GetHint(SDL_HINT_EMSCRIPTEN_KEYBOARD_ELEMENT);
   604     if (!keyElement) keyElement = "#window";
   605 
   606     emscripten_set_keydown_callback(keyElement, data, 0, Emscripten_HandleKey);
   607     emscripten_set_keyup_callback(keyElement, data, 0, Emscripten_HandleKey);
   608     emscripten_set_keypress_callback(keyElement, data, 0, Emscripten_HandleKeyPress);
   609 
   610     emscripten_set_fullscreenchange_callback("#document", data, 0, Emscripten_HandleFullscreenChange);
   611 
   612     emscripten_set_resize_callback("#window", data, 0, Emscripten_HandleResize);
   613 
   614     emscripten_set_visibilitychange_callback(data, 0, Emscripten_HandleVisibilityChange);
   615 }
   616 
   617 void
   618 Emscripten_UnregisterEventHandlers(SDL_WindowData *data)
   619 {
   620     /* only works due to having one window */
   621     emscripten_set_mousemove_callback("#canvas", NULL, 0, NULL);
   622 
   623     emscripten_set_mousedown_callback("#canvas", NULL, 0, NULL);
   624     emscripten_set_mouseup_callback("#document", NULL, 0, NULL);
   625 
   626     emscripten_set_mouseenter_callback("#canvas", NULL, 0, NULL);
   627     emscripten_set_mouseleave_callback("#canvas", NULL, 0, NULL);
   628 
   629     emscripten_set_wheel_callback("#canvas", NULL, 0, NULL);
   630 
   631     emscripten_set_focus_callback("#window", NULL, 0, NULL);
   632     emscripten_set_blur_callback("#window", NULL, 0, NULL);
   633 
   634     emscripten_set_touchstart_callback("#canvas", NULL, 0, NULL);
   635     emscripten_set_touchend_callback("#canvas", NULL, 0, NULL);
   636     emscripten_set_touchmove_callback("#canvas", NULL, 0, NULL);
   637     emscripten_set_touchcancel_callback("#canvas", NULL, 0, NULL);
   638 
   639     const char *target = SDL_GetHint(SDL_HINT_EMSCRIPTEN_KEYBOARD_ELEMENT);
   640     if (!target) {
   641         target = "#window";
   642     }
   643 
   644     emscripten_set_keydown_callback(target, NULL, 0, NULL);
   645     emscripten_set_keyup_callback(target, NULL, 0, NULL);
   646 
   647     emscripten_set_keypress_callback(target, NULL, 0, NULL);
   648 
   649     emscripten_set_fullscreenchange_callback("#document", NULL, 0, NULL);
   650 
   651     emscripten_set_resize_callback("#window", NULL, 0, NULL);
   652 
   653     emscripten_set_visibilitychange_callback(NULL, 0, NULL);
   654 }
   655 
   656 #endif /* SDL_VIDEO_DRIVER_EMSCRIPTEN */
   657 
   658 /* vi: set ts=4 sw=4 expandtab: */