21 lines
870 B
JavaScript
21 lines
870 B
JavaScript
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"use strict";
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function bindHorizontalBar(canvasElement, visualizerCore) {
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let _width = canvasElement.width;
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let _height = canvasElement.height;
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let _canvasCtx = canvasElement.getContext("2d");
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let _visualizerCore = visualizerCore;
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let update = function (delta, bins) {
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_canvasCtx.clearRect(0, 0, _width, _height); // clear canvas.
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let barWidth = Math.floor(_width / bins.length) - 1; // -1 for 1 pixel gap between bars.
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let barIndex = 0;
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bins.forEach(bin => {
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let normalBin = bin / 255.0;
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_canvasCtx.fillStyle = "rgb(" + 0 + "," + bin + "," + bin + ")";
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let barHeight = _height * normalBin;
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_canvasCtx.fillRect(barIndex * barWidth, _height - barHeight, barWidth, barHeight);
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barIndex += 1;
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});
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};
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_visualizerCore.addUpdateListener(update);
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}
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