1 /*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2021 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"
26 #include "SDL_emscriptenframebuffer.h"
27 #include "SDL_hints.h"
28
29
Emscripten_CreateWindowFramebuffer(_THIS,SDL_Window * window,Uint32 * format,void ** pixels,int * pitch)30 int Emscripten_CreateWindowFramebuffer(_THIS, SDL_Window * window, Uint32 * format, void ** pixels, int *pitch)
31 {
32 SDL_Surface *surface;
33 const Uint32 surface_format = SDL_PIXELFORMAT_BGR888;
34 int w, h;
35 int bpp;
36 Uint32 Rmask, Gmask, Bmask, Amask;
37
38 /* Free the old framebuffer surface */
39 SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
40 surface = data->surface;
41 SDL_FreeSurface(surface);
42
43 /* Create a new one */
44 SDL_PixelFormatEnumToMasks(surface_format, &bpp, &Rmask, &Gmask, &Bmask, &Amask);
45 SDL_GetWindowSize(window, &w, &h);
46
47 surface = SDL_CreateRGBSurface(0, w, h, bpp, Rmask, Gmask, Bmask, Amask);
48 if (!surface) {
49 return -1;
50 }
51
52 /* Save the info and return! */
53 data->surface = surface;
54 *format = surface_format;
55 *pixels = surface->pixels;
56 *pitch = surface->pitch;
57 return 0;
58 }
59
Emscripten_UpdateWindowFramebuffer(_THIS,SDL_Window * window,const SDL_Rect * rects,int numrects)60 int Emscripten_UpdateWindowFramebuffer(_THIS, SDL_Window * window, const SDL_Rect * rects, int numrects)
61 {
62 SDL_Surface *surface;
63
64 SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
65 surface = data->surface;
66 if (!surface) {
67 return SDL_SetError("Couldn't find framebuffer surface for window");
68 }
69
70 /* Send the data to the display */
71
72 EM_ASM_INT({
73 var w = $0;
74 var h = $1;
75 var pixels = $2;
76
77 if (!Module['SDL2']) Module['SDL2'] = {};
78 var SDL2 = Module['SDL2'];
79 if (SDL2.ctxCanvas !== Module['canvas']) {
80 SDL2.ctx = Module['createContext'](Module['canvas'], false, true);
81 SDL2.ctxCanvas = Module['canvas'];
82 }
83 if (SDL2.w !== w || SDL2.h !== h || SDL2.imageCtx !== SDL2.ctx) {
84 SDL2.image = SDL2.ctx.createImageData(w, h);
85 SDL2.w = w;
86 SDL2.h = h;
87 SDL2.imageCtx = SDL2.ctx;
88 }
89 var data = SDL2.image.data;
90 var src = pixels >> 2;
91 var dst = 0;
92 var num;
93 if (typeof CanvasPixelArray !== 'undefined' && data instanceof CanvasPixelArray) {
94 // IE10/IE11: ImageData objects are backed by the deprecated CanvasPixelArray,
95 // not UInt8ClampedArray. These don't have buffers, so we need to revert
96 // to copying a byte at a time. We do the undefined check because modern
97 // browsers do not define CanvasPixelArray anymore.
98 num = data.length;
99 while (dst < num) {
100 var val = HEAP32[src]; // This is optimized. Instead, we could do {{{ makeGetValue('buffer', 'dst', 'i32') }}};
101 data[dst ] = val & 0xff;
102 data[dst+1] = (val >> 8) & 0xff;
103 data[dst+2] = (val >> 16) & 0xff;
104 data[dst+3] = 0xff;
105 src++;
106 dst += 4;
107 }
108 } else {
109 if (SDL2.data32Data !== data) {
110 SDL2.data32 = new Int32Array(data.buffer);
111 SDL2.data8 = new Uint8Array(data.buffer);
112 SDL2.data32Data = data;
113 }
114 var data32 = SDL2.data32;
115 num = data32.length;
116 // logically we need to do
117 // while (dst < num) {
118 // data32[dst++] = HEAP32[src++] | 0xff000000
119 // }
120 // the following code is faster though, because
121 // .set() is almost free - easily 10x faster due to
122 // native SDL_memcpy efficiencies, and the remaining loop
123 // just stores, not load + store, so it is faster
124 data32.set(HEAP32.subarray(src, src + num));
125 var data8 = SDL2.data8;
126 var i = 3;
127 var j = i + 4*num;
128 if (num % 8 == 0) {
129 // unrolling gives big speedups
130 while (i < j) {
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 data8[i] = 0xff;
146 i = i + 4 | 0;
147 }
148 } else {
149 while (i < j) {
150 data8[i] = 0xff;
151 i = i + 4 | 0;
152 }
153 }
154 }
155
156 SDL2.ctx.putImageData(SDL2.image, 0, 0);
157 return 0;
158 }, surface->w, surface->h, surface->pixels);
159
160 if (emscripten_has_asyncify() && SDL_GetHintBoolean(SDL_HINT_EMSCRIPTEN_ASYNCIFY, SDL_TRUE)) {
161 /* give back control to browser for screen refresh */
162 emscripten_sleep(0);
163 }
164
165 return 0;
166 }
167
Emscripten_DestroyWindowFramebuffer(_THIS,SDL_Window * window)168 void Emscripten_DestroyWindowFramebuffer(_THIS, SDL_Window * window)
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: */
179