52 lines
1.4 KiB
JavaScript
52 lines
1.4 KiB
JavaScript
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function ImageData(arr, width, height) {
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if (!width || height === 0) {
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throw 'invalid dimensions, width and height must be non-zero';
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}
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if (arr.length % 4) {
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throw 'arr must be a multiple of 4';
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}
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height = height || arr.length/(4*width);
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Object.defineProperty(this, 'data', {
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value: arr,
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writable: false
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});
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Object.defineProperty(this, 'height', {
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value: height,
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writable: false
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});
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Object.defineProperty(this, 'width', {
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value: width,
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writable: false
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});
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}
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CanvasKit.ImageData = function() {
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if (arguments.length === 2) {
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var width = arguments[0];
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var height = arguments[1];
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var byteLength = 4 * width * height;
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return new ImageData(new Uint8ClampedArray(byteLength),
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width, height);
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} else if (arguments.length === 3) {
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var arr = arguments[0];
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if (arr.prototype.constructor !== Uint8ClampedArray ) {
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throw 'bytes must be given as a Uint8ClampedArray';
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}
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var width = arguments[1];
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var height = arguments[2];
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if (arr % 4) {
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throw 'bytes must be given in a multiple of 4';
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}
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if (arr % width) {
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throw 'bytes must divide evenly by width';
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}
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if (height && (height !== (arr / (width * 4)))) {
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throw 'invalid height given';
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}
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height = arr / (width * 4);
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return new ImageData(arr, width, height);
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} else {
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throw 'invalid number of arguments - takes 2 or 3, saw ' + arguments.length;
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}
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}
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