pixelbutler/build/core/ticker.js

Low-res bitmap render engine for big screens

'use strict';
function interval(callback, fps) {
    var intervalID = 0;
    var frame = 0;
    var prev = performance.now();
    function step() {
        if (intervalID) {
            frame++;
            var now = performance.now();
            callback(frame, now - prev);
            prev = now;
        }
    }
    var that = {};
    that.start = function () {
        if (intervalID) {
            clearInterval(intervalID);
        }
        intervalID = setInterval(step, 1000 / fps);
    };
    that.step = function () {
        step();
    };
    that.stop = function () {
        if (intervalID) {
            clearInterval(intervalID);
            intervalID = 0;
        }
    };
    that.isRunning = function () {
        return !!intervalID;
    };
    return that;
}
exports.interval = interval;
function request(callback) {
    var running = false;
    var frame = 0;
    var prev = performance.now();
    function step() {
        if (running) {
            frame++;
            var now = performance.now();
            callback(frame, now - prev);
            prev = now;
            requestAnimationFrame(step);
        }
    }
    var requestID;
    var that = {};
    that.start = function () {
        if (!running) {
            running = true;
            requestID = requestAnimationFrame(step);
        }
    };
    that.step = function () {
        step();
    };
    that.stop = function () {
        if (running) {
            running = false;
            cancelAnimationFrame(requestID);
        }
    };
    that.isRunning = function () {
        return running;
    };
    return that;
}
exports.request = request;