import CesiumMath from './Math.js';
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/**
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* @private
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*/
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var CylinderGeometryLibrary = {};
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/**
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* @private
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*/
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CylinderGeometryLibrary.computePositions = function(length, topRadius, bottomRadius, slices, fill){
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var topZ = length * 0.5;
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var bottomZ = -topZ;
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var twoSlice = slices + slices;
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var size = (fill) ? 2 * twoSlice : twoSlice;
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var positions = new Float64Array(size*3);
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var i;
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var index = 0;
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var tbIndex = 0;
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var bottomOffset = (fill) ? twoSlice*3 : 0;
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var topOffset = (fill) ? (twoSlice + slices)*3 : slices*3;
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for (i = 0; i < slices; i++) {
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var angle = i / slices * CesiumMath.TWO_PI;
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var x = Math.cos(angle);
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var y = Math.sin(angle);
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var bottomX = x * bottomRadius;
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var bottomY = y * bottomRadius;
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var topX = x * topRadius;
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var topY = y * topRadius;
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positions[tbIndex + bottomOffset] = bottomX;
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positions[tbIndex + bottomOffset + 1] = bottomY;
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positions[tbIndex + bottomOffset + 2] = bottomZ;
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positions[tbIndex + topOffset] = topX;
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positions[tbIndex + topOffset + 1] = topY;
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positions[tbIndex + topOffset + 2] = topZ;
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tbIndex += 3;
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if (fill) {
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positions[index++] = bottomX;
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positions[index++] = bottomY;
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positions[index++] = bottomZ;
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positions[index++] = topX;
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positions[index++] = topY;
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positions[index++] = topZ;
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}
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}
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return positions;
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};
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export default CylinderGeometryLibrary;
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