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1(function(SkottieKit){
2SkottieKit._extraInitializations = SkottieKit._extraInitializations || [];
3SkottieKit._extraInitializations.push(function() {
4  function get(obj, attr, defaultValue) {
5    if (obj && obj.hasOwnProperty(attr)) {
6      return obj[attr];
7    }
8    return defaultValue;
9  }
10
11  function makeWebGLContext(canvas, attrs) {
12    var contextAttributes = {
13      alpha: get(attrs, 'alpha', 1),
14      depth: get(attrs, 'depth', 1),
15      stencil: get(attrs, 'stencil', 8),
16      antialias: get(attrs, 'antialias', 1),
17      premultipliedAlpha: get(attrs, 'premultipliedAlpha', 1),
18      preserveDrawingBuffer: get(attrs, 'preserveDrawingBuffer', 0),
19      preferLowPowerToHighPerformance: get(attrs, 'preferLowPowerToHighPerformance', 0),
20      failIfMajorPerformanceCaveat: get(attrs, 'failIfMajorPerformanceCaveat', 0),
21      majorVersion: get(attrs, 'majorVersion', 2),
22      minorVersion: get(attrs, 'minorVersion', 0),
23      enableExtensionsByDefault: get(attrs, 'enableExtensionsByDefault', 1),
24      explicitSwapControl: get(attrs, 'explicitSwapControl', 0),
25      renderViaOffscreenBackBuffer: get(attrs, 'renderViaOffscreenBackBuffer', 0),
26    };
27    if (!canvas) {
28      SkDebug('null canvas passed into makeWebGLContext');
29      return 0;
30    }
31    // This check is from the emscripten version
32    if (contextAttributes['explicitSwapControl']) {
33      SkDebug('explicitSwapControl is not supported');
34      return 0;
35    }
36    // GL is an enscripten provided helper
37    // See https://github.com/emscripten-core/emscripten/blob/incoming/src/library_webgl.js
38    var ctx = GL.createContext(canvas, contextAttributes);
39
40    if (!ctx && contextAttributes.majorVersion > 1) {
41      contextAttributes.majorVersion = 1;  // fall back to WebGL 1.0
42      contextAttributes.minorVersion = 0;
43      ctx = GL.createContext(canvas, contextAttributes);
44    }
45    return ctx;
46  }
47
48  SkottieKit.GetWebGLContext = function(canvas, attrs) {
49    return makeWebGLContext(canvas, attrs);
50  };
51
52  // arg can be of types:
53  //  - String - in which case it is interpreted as an id of a
54  //          canvas element.
55  //  - HTMLCanvasElement - in which the provided canvas element will
56  //          be used directly.
57  // Width and height can be provided to override those on the canvas
58  // element, or specify a height for when a context is provided.
59  SkottieKit.MakeWebGLCanvasSurface = function(arg, width, height) {
60    var canvas = arg;
61    if (canvas.tagName !== 'CANVAS') {
62      canvas = document.getElementById(arg);
63      if (!canvas) {
64        throw 'Canvas with id ' + arg + ' was not found';
65      }
66    }
67    // we are ok with all the defaults
68    var ctx = this.GetWebGLContext(canvas);
69
70    if (!ctx || ctx < 0) {
71      throw 'failed to create webgl context: err ' + ctx;
72    }
73
74    if (!canvas && (!width || !height)) {
75      throw 'height and width must be provided with context';
76    }
77
78    var grcontext = this.MakeGrContext(ctx);
79
80    // if (grcontext) {
81    //    // Bump the default resource cache limit.
82    //   var RESOURCE_CACHE_BYTES = 256 * 1024 * 1024;
83    //   grcontext.setResourceCacheLimitBytes(RESOURCE_CACHE_BYTES);
84    // }
85
86
87    // Maybe better to use clientWidth/height.  See:
88    // https://webglfundamentals.org/webgl/lessons/webgl-anti-patterns.html
89    var surface = this.MakeOnScreenGLSurface(grcontext,
90                                             width  || canvas.width,
91                                             height || canvas.height);
92    if (!surface) {
93      SkDebug('falling back from GPU implementation to a SW based one');
94      // we need to throw away the old canvas (which was locked to
95      // a webGL context) and create a new one so we can
96      var newCanvas = canvas.cloneNode(true);
97      var parent = canvas.parentNode;
98      parent.replaceChild(newCanvas, canvas);
99      // add a class so the user can detect that it was replaced.
100      newCanvas.classList.add('ck-replaced');
101
102      return SkottieKit.MakeSWCanvasSurface(newCanvas);
103    }
104    surface._context = ctx;
105    surface.grContext = grcontext;
106    return surface;
107  };
108  // Default to trying WebGL first.
109  SkottieKit.MakeCanvasSurface = SkottieKit.MakeWebGLCanvasSurface;
110});
111}(Module)); // When this file is loaded in, the high level object is "Module";
112