tsparticles-engine/browser/Core/Retina.js

Easily create highly customizable particle, confetti and fireworks animations and use them as animated backgrounds for your website. Ready to use components available also for React, Vue.js (2.x and 3.x), Angular, Svelte, jQuery, Preact, Riot.js, Inferno.

import { getRangeValue } from "../Utils/NumberUtils";
import { isSsr } from "../Utils/Utils";
export class Retina {
    constructor(container) {
        this.container = container;
        this.pixelRatio = 1;
        this.reduceFactor = 1;
    }
    init() {
        const container = this.container, options = container.actualOptions;
        this.pixelRatio = !options.detectRetina || isSsr() ? 1 : window.devicePixelRatio;
        this.reduceFactor = 1;
        const ratio = this.pixelRatio;
        if (container.canvas.element) {
            const element = container.canvas.element;
            container.canvas.size.width = element.offsetWidth * ratio;
            container.canvas.size.height = element.offsetHeight * ratio;
        }
        const particles = options.particles, moveOptions = particles.move;
        this.attractDistance = getRangeValue(moveOptions.attract.distance) * ratio;
        this.maxSpeed = getRangeValue(moveOptions.gravity.maxSpeed) * ratio;
        this.sizeAnimationSpeed = getRangeValue(particles.size.animation.speed) * ratio;
    }
    initParticle(particle) {
        const options = particle.options, ratio = this.pixelRatio, moveOptions = options.move, moveDistance = moveOptions.distance, props = particle.retina;
        props.attractDistance = getRangeValue(moveOptions.attract.distance) * ratio;
        props.moveDrift = getRangeValue(moveOptions.drift) * ratio;
        props.moveSpeed = getRangeValue(moveOptions.speed) * ratio;
        props.sizeAnimationSpeed = getRangeValue(options.size.animation.speed) * ratio;
        const maxDistance = props.maxDistance;
        maxDistance.horizontal = moveDistance.horizontal !== undefined ? moveDistance.horizontal * ratio : undefined;
        maxDistance.vertical = moveDistance.vertical !== undefined ? moveDistance.vertical * ratio : undefined;
        props.maxSpeed = getRangeValue(moveOptions.gravity.maxSpeed) * ratio;
    }
}