playcanvas/build/playcanvas.dbg/src/core/math/kernel.js

PlayCanvas WebGL game engine

/**
 * Sampling kernels.
 *
 * @namespace
 * @category Math
 */ class Kernel {
    /**
     * Generate a set of points distributed in a series of concentric rings around the origin. The
     * spacing between points is determined by the number of points in the first ring, and subsequent
     * rings maintain this spacing by adjusting their number of points accordingly.
     *
     * @param {number} numRings - The number of concentric rings to generate.
     * @param {number} numPoints - The number of points in the first ring.
     * @returns {Array<number>} - An array where each point is represented by two numbers.
     */ static concentric(numRings, numPoints) {
        var kernel = [];
        // center point
        kernel.push(0, 0);
        // spacing based on the first ring
        var spacing = 2 * Math.PI / numRings / numPoints;
        // Generate points for each ring
        for(var ring = 1; ring <= numRings; ring++){
            var radius = ring / numRings;
            var circumference = 2 * Math.PI * radius;
            var pointsPerRing = Math.max(1, Math.floor(circumference / spacing));
            var angleStep = 2 * Math.PI / pointsPerRing;
            for(var point = 0; point < pointsPerRing; point++){
                var angle = point * angleStep;
                var x = radius * Math.cos(angle);
                var y = radius * Math.sin(angle);
                kernel.push(x, y);
            }
        }
        return kernel;
    }
}

export { Kernel };