SDL  2.0
SDL_emscriptenframebuffer.c
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2018 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_emscriptenvideo.h"
27 
28 
30 {
32  const Uint32 surface_format = SDL_PIXELFORMAT_BGR888;
33  int w, h;
34  int bpp;
35  Uint32 Rmask, Gmask, Bmask, Amask;
36 
37  /* Free the old framebuffer surface */
39  surface = data->surface;
40  SDL_FreeSurface(surface);
41 
42  /* Create a new one */
43  SDL_PixelFormatEnumToMasks(surface_format, &bpp, &Rmask, &Gmask, &Bmask, &Amask);
44  SDL_GetWindowSize(window, &w, &h);
45 
46  surface = SDL_CreateRGBSurface(0, w, h, bpp, Rmask, Gmask, Bmask, Amask);
47  if (!surface) {
48  return -1;
49  }
50 
51  /* Save the info and return! */
52  data->surface = surface;
53  *format = surface_format;
54  *pixels = surface->pixels;
55  *pitch = surface->pitch;
56  return 0;
57 }
58 
59 int Emscripten_UpdateWindowFramebuffer(_THIS, SDL_Window * window, const SDL_Rect * rects, int numrects)
60 {
62 
63  SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
64  surface = data->surface;
65  if (!surface) {
66  return SDL_SetError("Couldn't find framebuffer surface for window");
67  }
68 
69  /* Send the data to the display */
70 
71  EM_ASM_INT({
72  var w = $0;
73  var h = $1;
74  var pixels = $2;
75 
76  if (!Module['SDL2']) Module['SDL2'] = {};
77  var SDL2 = Module['SDL2'];
78  if (SDL2.ctxCanvas !== Module['canvas']) {
79  SDL2.ctx = Module['createContext'](Module['canvas'], false, true);
80  SDL2.ctxCanvas = Module['canvas'];
81  }
82  if (SDL2.w !== w || SDL2.h !== h || SDL2.imageCtx !== SDL2.ctx) {
83  SDL2.image = SDL2.ctx.createImageData(w, h);
84  SDL2.w = w;
85  SDL2.h = h;
86  SDL2.imageCtx = SDL2.ctx;
87  }
88  var data = SDL2.image.data;
89  var src = pixels >> 2;
90  var dst = 0;
91  var num;
92  if (typeof CanvasPixelArray !== 'undefined' && data instanceof CanvasPixelArray) {
93  // IE10/IE11: ImageData objects are backed by the deprecated CanvasPixelArray,
94  // not UInt8ClampedArray. These don't have buffers, so we need to revert
95  // to copying a byte at a time. We do the undefined check because modern
96  // browsers do not define CanvasPixelArray anymore.
97  num = data.length;
98  while (dst < num) {
99  var val = HEAP32[src]; // This is optimized. Instead, we could do {{{ makeGetValue('buffer', 'dst', 'i32') }}};
100  data[dst ] = val & 0xff;
101  data[dst+1] = (val >> 8) & 0xff;
102  data[dst+2] = (val >> 16) & 0xff;
103  data[dst+3] = 0xff;
104  src++;
105  dst += 4;
106  }
107  } else {
108  if (SDL2.data32Data !== data) {
109  SDL2.data32 = new Int32Array(data.buffer);
110  SDL2.data8 = new Uint8Array(data.buffer);
111  }
112  var data32 = SDL2.data32;
113  num = data32.length;
114  // logically we need to do
115  // while (dst < num) {
116  // data32[dst++] = HEAP32[src++] | 0xff000000
117  // }
118  // the following code is faster though, because
119  // .set() is almost free - easily 10x faster due to
120  // native memcpy efficiencies, and the remaining loop
121  // just stores, not load + store, so it is faster
122  data32.set(HEAP32.subarray(src, src + num));
123  var data8 = SDL2.data8;
124  var i = 3;
125  var j = i + 4*num;
126  if (num % 8 == 0) {
127  // unrolling gives big speedups
128  while (i < j) {
129  data8[i] = 0xff;
130  i = i + 4 | 0;
131  data8[i] = 0xff;
132  i = i + 4 | 0;
133  data8[i] = 0xff;
134  i = i + 4 | 0;
135  data8[i] = 0xff;
136  i = i + 4 | 0;
137  data8[i] = 0xff;
138  i = i + 4 | 0;
139  data8[i] = 0xff;
140  i = i + 4 | 0;
141  data8[i] = 0xff;
142  i = i + 4 | 0;
143  data8[i] = 0xff;
144  i = i + 4 | 0;
145  }
146  } else {
147  while (i < j) {
148  data8[i] = 0xff;
149  i = i + 4 | 0;
150  }
151  }
152  }
153 
154  SDL2.ctx.putImageData(SDL2.image, 0, 0);
155  return 0;
156  }, surface->w, surface->h, surface->pixels);
157 
158  /*if (SDL_getenv("SDL_VIDEO_Emscripten_SAVE_FRAMES")) {
159  static int frame_number = 0;
160  char file[128];
161  SDL_snprintf(file, sizeof(file), "SDL_window%d-%8.8d.bmp",
162  SDL_GetWindowID(window), ++frame_number);
163  SDL_SaveBMP(surface, file);
164  }*/
165  return 0;
166 }
167 
169 {
170  SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
171 
172  SDL_FreeSurface(data->surface);
173  data->surface = NULL;
174 }
175 
176 #endif /* SDL_VIDEO_DRIVER_EMSCRIPTEN */
177 
178 /* vi: set ts=4 sw=4 expandtab: */
GLuint num
GLenum GLenum dst
GLfloat GLfloat GLfloat GLfloat h
EGLSurface surface
Definition: eglext.h:248
A collection of pixels used in software blitting.
Definition: SDL_surface.h:69
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: SDL_opengl.h:1974
uint32_t Uint32
Definition: SDL_stdinc.h:181
void Emscripten_DestroyWindowFramebuffer(_THIS, SDL_Window *window)
GLenum src
SDL_Surface * surface
GLint GLint GLsizei GLsizei GLsizei GLint GLenum format
Definition: SDL_opengl.h:1572
#define SDL_GetWindowSize
int Emscripten_CreateWindowFramebuffer(_THIS, SDL_Window *window, Uint32 *format, void **pixels, int *pitch)
GLuint GLfloat * val
void * pixels
Definition: SDL_surface.h:75
#define SDL_FreeSurface
#define _THIS
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 in j)
Definition: SDL_x11sym.h:50
GLubyte GLubyte GLubyte GLubyte w
#define SDL_PixelFormatEnumToMasks
GLint GLint GLsizei GLsizei GLsizei GLint GLenum GLenum const GLvoid * pixels
Definition: SDL_opengl.h:1572
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
#define NULL
Definition: begin_code.h:164
#define SDL_SetError
#define SDL_CreateRGBSurface
EGLSurface EGLNativeWindowType * window
Definition: eglext.h:1025
The type used to identify a window.
Definition: SDL_sysvideo.h:73
void * driverdata
Definition: SDL_sysvideo.h:111
EGLSurface EGLint * rects
Definition: eglext.h:282
int Emscripten_UpdateWindowFramebuffer(_THIS, SDL_Window *window, const SDL_Rect *rects, int numrects)
A rectangle, with the origin at the upper left.
Definition: SDL_rect.h:64