src/video/emscripten/SDL_emscriptenvideo.c
author Sylvain Becker <sylvain.becker@gmail.com>
Mon, 17 Jun 2019 22:31:36 +0200
changeset 12871 ab4d52e38c42
parent 12724 19c373658809
permissions -rw-r--r--
Fixed bug 4669: Android software renderer, black screen when window resizes

Using the software SDL_Renderer on Android leads to GL errors & black screen when window resizes
     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 #include "../../SDL_internal.h"
    22 
    23 #if SDL_VIDEO_DRIVER_EMSCRIPTEN
    24 
    25 #include "SDL_video.h"
    26 #include "SDL_mouse.h"
    27 #include "SDL_hints.h"
    28 #include "../SDL_sysvideo.h"
    29 #include "../SDL_pixels_c.h"
    30 #include "../SDL_egl_c.h"
    31 #include "../../events/SDL_events_c.h"
    32 
    33 #include "SDL_emscriptenvideo.h"
    34 #include "SDL_emscriptenopengles.h"
    35 #include "SDL_emscriptenframebuffer.h"
    36 #include "SDL_emscriptenevents.h"
    37 #include "SDL_emscriptenmouse.h"
    38 
    39 #define EMSCRIPTENVID_DRIVER_NAME "emscripten"
    40 
    41 /* Initialization/Query functions */
    42 static int Emscripten_VideoInit(_THIS);
    43 static int Emscripten_SetDisplayMode(_THIS, SDL_VideoDisplay * display, SDL_DisplayMode * mode);
    44 static void Emscripten_VideoQuit(_THIS);
    45 
    46 static int Emscripten_CreateWindow(_THIS, SDL_Window * window);
    47 static void Emscripten_SetWindowSize(_THIS, SDL_Window * window);
    48 static void Emscripten_DestroyWindow(_THIS, SDL_Window * window);
    49 static void Emscripten_SetWindowFullscreen(_THIS, SDL_Window * window, SDL_VideoDisplay * display, SDL_bool fullscreen);
    50 static void Emscripten_PumpEvents(_THIS);
    51 static void Emscripten_SetWindowTitle(_THIS, SDL_Window * window);
    52 
    53 
    54 /* Emscripten driver bootstrap functions */
    55 
    56 static int
    57 Emscripten_Available(void)
    58 {
    59     return (1);
    60 }
    61 
    62 static void
    63 Emscripten_DeleteDevice(SDL_VideoDevice * device)
    64 {
    65     SDL_free(device);
    66 }
    67 
    68 static SDL_VideoDevice *
    69 Emscripten_CreateDevice(int devindex)
    70 {
    71     SDL_VideoDevice *device;
    72 
    73     /* Initialize all variables that we clean on shutdown */
    74     device = (SDL_VideoDevice *) SDL_calloc(1, sizeof(SDL_VideoDevice));
    75     if (!device) {
    76         SDL_OutOfMemory();
    77         return (0);
    78     }
    79 
    80     /* Firefox sends blur event which would otherwise prevent full screen
    81      * when the user clicks to allow full screen.
    82      * See https://bugzilla.mozilla.org/show_bug.cgi?id=1144964
    83     */
    84     SDL_SetHint(SDL_HINT_VIDEO_MINIMIZE_ON_FOCUS_LOSS, "0");
    85 
    86     /* Set the function pointers */
    87     device->VideoInit = Emscripten_VideoInit;
    88     device->VideoQuit = Emscripten_VideoQuit;
    89     device->SetDisplayMode = Emscripten_SetDisplayMode;
    90 
    91 
    92     device->PumpEvents = Emscripten_PumpEvents;
    93 
    94     device->CreateSDLWindow = Emscripten_CreateWindow;
    95     device->SetWindowTitle = Emscripten_SetWindowTitle;
    96     /*device->SetWindowIcon = Emscripten_SetWindowIcon;
    97     device->SetWindowPosition = Emscripten_SetWindowPosition;*/
    98     device->SetWindowSize = Emscripten_SetWindowSize;
    99     /*device->ShowWindow = Emscripten_ShowWindow;
   100     device->HideWindow = Emscripten_HideWindow;
   101     device->RaiseWindow = Emscripten_RaiseWindow;
   102     device->MaximizeWindow = Emscripten_MaximizeWindow;
   103     device->MinimizeWindow = Emscripten_MinimizeWindow;
   104     device->RestoreWindow = Emscripten_RestoreWindow;
   105     device->SetWindowGrab = Emscripten_SetWindowGrab;*/
   106     device->DestroyWindow = Emscripten_DestroyWindow;
   107     device->SetWindowFullscreen = Emscripten_SetWindowFullscreen;
   108 
   109     device->CreateWindowFramebuffer = Emscripten_CreateWindowFramebuffer;
   110     device->UpdateWindowFramebuffer = Emscripten_UpdateWindowFramebuffer;
   111     device->DestroyWindowFramebuffer = Emscripten_DestroyWindowFramebuffer;
   112 
   113 #if SDL_VIDEO_OPENGL_EGL
   114     device->GL_LoadLibrary = Emscripten_GLES_LoadLibrary;
   115     device->GL_GetProcAddress = Emscripten_GLES_GetProcAddress;
   116     device->GL_UnloadLibrary = Emscripten_GLES_UnloadLibrary;
   117     device->GL_CreateContext = Emscripten_GLES_CreateContext;
   118     device->GL_MakeCurrent = Emscripten_GLES_MakeCurrent;
   119     device->GL_SetSwapInterval = Emscripten_GLES_SetSwapInterval;
   120     device->GL_GetSwapInterval = Emscripten_GLES_GetSwapInterval;
   121     device->GL_SwapWindow = Emscripten_GLES_SwapWindow;
   122     device->GL_DeleteContext = Emscripten_GLES_DeleteContext;
   123     device->GL_GetDrawableSize = Emscripten_GLES_GetDrawableSize;
   124 #endif
   125 
   126     device->free = Emscripten_DeleteDevice;
   127 
   128     return device;
   129 }
   130 
   131 VideoBootStrap Emscripten_bootstrap = {
   132     EMSCRIPTENVID_DRIVER_NAME, "SDL emscripten video driver",
   133     Emscripten_Available, Emscripten_CreateDevice
   134 };
   135 
   136 
   137 int
   138 Emscripten_VideoInit(_THIS)
   139 {
   140     SDL_DisplayMode mode;
   141 
   142     /* Use a fake 32-bpp desktop mode */
   143     mode.format = SDL_PIXELFORMAT_RGB888;
   144 
   145     mode.w = EM_ASM_INT_V({
   146         return screen.width;
   147     });
   148 
   149     mode.h = EM_ASM_INT_V({
   150         return screen.height;
   151     });
   152 
   153     mode.refresh_rate = 0;
   154     mode.driverdata = NULL;
   155     if (SDL_AddBasicVideoDisplay(&mode) < 0) {
   156         return -1;
   157     }
   158 
   159     SDL_AddDisplayMode(&_this->displays[0], &mode);
   160 
   161     Emscripten_InitMouse();
   162 
   163     /* We're done! */
   164     return 0;
   165 }
   166 
   167 static int
   168 Emscripten_SetDisplayMode(_THIS, SDL_VideoDisplay * display, SDL_DisplayMode * mode)
   169 {
   170     /* can't do this */
   171     return 0;
   172 }
   173 
   174 static void
   175 Emscripten_VideoQuit(_THIS)
   176 {
   177     Emscripten_FiniMouse();
   178 }
   179 
   180 static void
   181 Emscripten_PumpEvents(_THIS)
   182 {
   183     /* do nothing. */
   184 }
   185 
   186 static int
   187 Emscripten_CreateWindow(_THIS, SDL_Window * window)
   188 {
   189     SDL_WindowData *wdata;
   190     double scaled_w, scaled_h;
   191     double css_w, css_h;
   192 
   193     /* Allocate window internal data */
   194     wdata = (SDL_WindowData *) SDL_calloc(1, sizeof(SDL_WindowData));
   195     if (wdata == NULL) {
   196         return SDL_OutOfMemory();
   197     }
   198 
   199     wdata->canvas_id = SDL_strdup("#canvas");
   200 
   201     if (window->flags & SDL_WINDOW_ALLOW_HIGHDPI) {
   202         wdata->pixel_ratio = emscripten_get_device_pixel_ratio();
   203     } else {
   204         wdata->pixel_ratio = 1.0f;
   205     }
   206 
   207     scaled_w = SDL_floor(window->w * wdata->pixel_ratio);
   208     scaled_h = SDL_floor(window->h * wdata->pixel_ratio);
   209 
   210     /* set a fake size to check if there is any CSS sizing the canvas */
   211     emscripten_set_canvas_element_size(wdata->canvas_id, 1, 1);
   212     emscripten_get_element_css_size(wdata->canvas_id, &css_w, &css_h);
   213 
   214     wdata->external_size = SDL_floor(css_w) != 1 || SDL_floor(css_h) != 1;
   215 
   216     if ((window->flags & SDL_WINDOW_RESIZABLE) && wdata->external_size) {
   217         /* external css has resized us */
   218         scaled_w = css_w * wdata->pixel_ratio;
   219         scaled_h = css_h * wdata->pixel_ratio;
   220 
   221         SDL_SendWindowEvent(window, SDL_WINDOWEVENT_RESIZED, css_w, css_h);
   222     }
   223     emscripten_set_canvas_element_size(wdata->canvas_id, scaled_w, scaled_h);
   224 
   225     /* if the size is not being controlled by css, we need to scale down for hidpi */
   226     if (!wdata->external_size) {
   227         if (wdata->pixel_ratio != 1.0f) {
   228             /*scale canvas down*/
   229             emscripten_set_element_css_size(wdata->canvas_id, window->w, window->h);
   230         }
   231     }
   232 
   233 #if SDL_VIDEO_OPENGL_EGL
   234     if (window->flags & SDL_WINDOW_OPENGL) {
   235         if (!_this->egl_data) {
   236             if (SDL_GL_LoadLibrary(NULL) < 0) {
   237                 return -1;
   238             }
   239         }
   240         wdata->egl_surface = SDL_EGL_CreateSurface(_this, 0);
   241 
   242         if (wdata->egl_surface == EGL_NO_SURFACE) {
   243             return SDL_SetError("Could not create GLES window surface");
   244         }
   245     }
   246 #endif
   247 
   248     wdata->window = window;
   249 
   250     /* Setup driver data for this window */
   251     window->driverdata = wdata;
   252 
   253     /* One window, it always has focus */
   254     SDL_SetMouseFocus(window);
   255     SDL_SetKeyboardFocus(window);
   256 
   257     Emscripten_RegisterEventHandlers(wdata);
   258 
   259     /* Window has been successfully created */
   260     return 0;
   261 }
   262 
   263 static void Emscripten_SetWindowSize(_THIS, SDL_Window * window)
   264 {
   265     SDL_WindowData *data;
   266 
   267     if (window->driverdata) {
   268         data = (SDL_WindowData *) window->driverdata;
   269         /* update pixel ratio */
   270         if (window->flags & SDL_WINDOW_ALLOW_HIGHDPI) {
   271             data->pixel_ratio = emscripten_get_device_pixel_ratio();
   272         }
   273         emscripten_set_canvas_element_size(data->canvas_id, window->w * data->pixel_ratio, window->h * data->pixel_ratio);
   274 
   275         /*scale canvas down*/
   276         if (!data->external_size && data->pixel_ratio != 1.0f) {
   277             emscripten_set_element_css_size(data->canvas_id, window->w, window->h);
   278         }
   279     }
   280 }
   281 
   282 static void
   283 Emscripten_DestroyWindow(_THIS, SDL_Window * window)
   284 {
   285     SDL_WindowData *data;
   286 
   287     if(window->driverdata) {
   288         data = (SDL_WindowData *) window->driverdata;
   289 
   290         Emscripten_UnregisterEventHandlers(data);
   291 #if SDL_VIDEO_OPENGL_EGL
   292         if (data->egl_surface != EGL_NO_SURFACE) {
   293             SDL_EGL_DestroySurface(_this, data->egl_surface);
   294             data->egl_surface = EGL_NO_SURFACE;
   295         }
   296 #endif
   297 
   298         /* We can't destroy the canvas, so resize it to zero instead */
   299         emscripten_set_canvas_element_size(data->canvas_id, 0, 0);
   300         SDL_free(data->canvas_id);
   301 
   302         SDL_free(window->driverdata);
   303         window->driverdata = NULL;
   304     }
   305 }
   306 
   307 static void
   308 Emscripten_SetWindowFullscreen(_THIS, SDL_Window * window, SDL_VideoDisplay * display, SDL_bool fullscreen)
   309 {
   310     SDL_WindowData *data;
   311     if(window->driverdata) {
   312         data = (SDL_WindowData *) window->driverdata;
   313 
   314         if(fullscreen) {
   315             EmscriptenFullscreenStrategy strategy;
   316             SDL_bool is_desktop_fullscreen = (window->flags & SDL_WINDOW_FULLSCREEN_DESKTOP) == SDL_WINDOW_FULLSCREEN_DESKTOP;
   317             int res;
   318 
   319             strategy.scaleMode = is_desktop_fullscreen ? EMSCRIPTEN_FULLSCREEN_SCALE_STRETCH : EMSCRIPTEN_FULLSCREEN_SCALE_ASPECT;
   320 
   321             if(!is_desktop_fullscreen) {
   322                 strategy.canvasResolutionScaleMode = EMSCRIPTEN_FULLSCREEN_CANVAS_SCALE_NONE;
   323             } else if(window->flags & SDL_WINDOW_ALLOW_HIGHDPI) {
   324                 strategy.canvasResolutionScaleMode = EMSCRIPTEN_FULLSCREEN_CANVAS_SCALE_HIDEF;
   325             } else {
   326                 strategy.canvasResolutionScaleMode = EMSCRIPTEN_FULLSCREEN_CANVAS_SCALE_STDDEF;
   327             }
   328 
   329             strategy.filteringMode = EMSCRIPTEN_FULLSCREEN_FILTERING_DEFAULT;
   330 
   331             strategy.canvasResizedCallback = Emscripten_HandleCanvasResize;
   332             strategy.canvasResizedCallbackUserData = data;
   333 
   334             data->requested_fullscreen_mode = window->flags & (SDL_WINDOW_FULLSCREEN_DESKTOP | SDL_WINDOW_FULLSCREEN);
   335             data->fullscreen_resize = is_desktop_fullscreen;
   336 
   337             res = emscripten_request_fullscreen_strategy(data->canvas_id, 1, &strategy);
   338             if(res != EMSCRIPTEN_RESULT_SUCCESS && res != EMSCRIPTEN_RESULT_DEFERRED) {
   339                 /* unset flags, fullscreen failed */
   340                 window->flags &= ~(SDL_WINDOW_FULLSCREEN_DESKTOP | SDL_WINDOW_FULLSCREEN);
   341             }
   342         }
   343         else
   344             emscripten_exit_fullscreen();
   345     }
   346 }
   347 
   348 static void
   349 Emscripten_SetWindowTitle(_THIS, SDL_Window * window) {
   350     EM_ASM_INT({
   351       if (typeof Module['setWindowTitle'] !== 'undefined') {
   352         Module['setWindowTitle'](UTF8ToString($0));
   353       }
   354       return 0;
   355     }, window->title);
   356 }
   357 
   358 #endif /* SDL_VIDEO_DRIVER_EMSCRIPTEN */
   359 
   360 /* vi: set ts=4 sw=4 expandtab: */