voluptasquisquam/src/image/operator/paintPoints.js

Image processing and manipulation in JavaScript

import Shape from '../../util/Shape';

/**
 * Paint pixels on the current image.
 * @memberof Image
 * @instance
 * @param {Array<Array<number>>} points - Array of [x,y] points
 * @param {object} [options]
 * @param {Array<number>} [options.color=[max,0,0]] - Array of 3 elements (R, G, B), default is red.
 * @param {object} [options.shape] - Definition of the shape, see Shape contructor.
 * @return {this} The original painted image
 */
export default function paintPoints(points, options = {}) {
    let {
        color = [this.maxValue, 0, 0],
        shape
    } = options;

    this.checkProcessable('paintPoints', {
        bitDepth: [8, 16]
    });

    let shapePixels = (new Shape(shape)).getPoints();

    let numberChannels = Math.min(this.channels, color.length);

    for (let i = 0; i < points.length; i++) {
        let xP = points[i][0];
        let yP = points[i][1];
        for (let j = 0; j < shapePixels.length; j++) {
            let xS = shapePixels[j][0];
            let yS = shapePixels[j][1];
            if (
                ((xP + xS) >= 0) &&
                ((yP + yS) >= 0) &&
                ((xP + xS) < this.width) &&
                ((yP + yS) < this.height)
            ) {
                let position = (xP + xS + (yP + yS) * this.width) * this.channels;
                for (let channel = 0; channel < numberChannels; channel++) {
                    this.data[position + channel] = color[channel];
                }
            }
        }
    }

    return this;
}