26 lines
624 B
JavaScript
26 lines
624 B
JavaScript
function makePattern(len, start, inc) {
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var pattern = [];
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while(len) {
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pattern.push(start);
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start = (start + inc) % 256;
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--len;
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}
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return pattern;
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}
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function setPattern(imageData, pattern) {
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if (pattern.length != imageData.data.length)
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throw Error('Invalid pattern');
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for (var i = 0; i < pattern.length; ++i)
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imageData.data[i] = pattern[i];
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}
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function checkPattern(imageData, pattern) {
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if (pattern.length != imageData.data.length)
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throw Error('Invalid pattern');
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for (var i = 0; i < pattern.length; ++i)
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if (imageData.data[i] != pattern[i])
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return false;
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return true;
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}
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