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mikemorris/Canvas Pixel Map

Created August 13, 2012 15:52
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Canvas pixel map technique from Paul Bakaus' Google Talk http://www.youtube.com/watch?v=_RRnyChxijA&feature=related
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Canvas Pixel Map
var clickMap = [];
for (var i = 0; n = imageData.length; i < n; i += 4) {
var row = Math.floor((i/4) / width);
var col = (i/4) - (row * width);
if(!clickMap[row]) clickMap[row] = [];
clickMap[row][col] = imageData[i+3] == 0 ? 0 : 1;
}
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