function collectPointData()

in toolkit/jb/shared.js [449:502]

• 34 lines of code
• 10 McCabe index (conditional complexity)

function collectPointData(pixels, config) {

    var srcPixels = pixels.values;

    if (!srcPixels || !srcPixels.length) return [];

    var step = Math.floor(config.step || pixels.step);

    if (!step) return [];

    var chaos = config.chaos / 100;
    var d = pixels.density;
    var srcWidth = pixels.width;
    var srcHeight = pixels.height;
    var low = config.low;
    var high = config.high;

    var dsrcWidth = srcWidth * d;
    var dsrcHeight = srcHeight * d;

    var maxPoints =  dsrcWidth * dsrcHeight * 4;

    /* console.log('collectPointData', dsrcWidth, 'x', dsrcHeight, 'pixels length', srcPixels.length,
                'expected length', maxPoints); */

    var idx, pxBrightness, r, g, b, a;

    var lastPoint;

    var pointData = [];

    var xpos, ypos;


    for (var x = 0; x < srcWidth; x += step) {
        for (var y = 0; y < srcHeight; y += step) {
            // console.log('y', y, pointData.length >= maxPoints);
            pxBrightness = pixelBrightnessByCoords(x, y, srcPixels, srcWidth, d);

            if ((pxBrightness > low) && (random(0, pxBrightness) < high)) {

                xpos = x + random(-step / 2, step / 2) * chaos;
                ypos = y + random(-step / 2, step / 2) * chaos;

                pointData.push([ xpos, ypos, pxBrightness ]);
                if (pointData.length >= maxPoints) break;
            }

        }

    }

    return pointData;
}