【发布时间】：2020-02-27 17:15:22
【问题描述】：
我正在尝试更新现有的particle animation。在这个演示中，粒子只是具有不同lineWidths 的线条，它们在下落时具有随机大小和旋转。
我的目标是用不同的形状替换线条，如下图所示，保持其他所有内容不变。
我已经改变了形状，但我遇到了几个问题：
- 它不再像上面发布的原始演示链接那样旋转。
- 因为我用形状的图像替换了线条，所以如果我增加粒子，我也会面临性能问题。
-
如果我随机化大小，它会不断更新形状的大小，而不保持第一个随机大小。
context.drawImage(svg, x, y, 20, 40) | v context.drawImage(svg, x, y, Math.random() * 20, Math.random() * 40)
谁能指出我应该解决上述问题的正确方向。感谢任何帮助！
var confetti = {
maxCount: 150, //set max confetti count
speed: 1, //set the particle animation speed
frameInterval: 30, //the confetti animation frame interval in milliseconds
alpha: 1.0, //the alpha opacity of the confetti (between 0 and 1, where 1 is opaque and 0 is invisible)
gradient: false, //whether to use gradients for the confetti particles
start: null, //call to start confetti animation (with optional timeout in milliseconds, and optional min and max random confetti count)
stop: null, //call to stop adding confetti
toggle: null, //call to start or stop the confetti animation depending on whether it's already running
pause: null, //call to freeze confetti animation
resume: null, //call to unfreeze confetti animation
togglePause: null, //call to toggle whether the confetti animation is paused
remove: null, //call to stop the confetti animation and remove all confetti immediately
isPaused: null, //call and returns true or false depending on whether the confetti animation is paused
isRunning: null //call and returns true or false depending on whether the animation is running
};
(function() {
confetti.start = startConfetti;
confetti.stop = stopConfetti;
confetti.toggle = toggleConfetti;
confetti.pause = pauseConfetti;
confetti.resume = resumeConfetti;
confetti.togglePause = toggleConfettiPause;
confetti.isPaused = isConfettiPaused;
confetti.remove = removeConfetti;
confetti.isRunning = isConfettiRunning;
var supportsAnimationFrame = window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame;
var colors = ["rgba(30,144,255,", "rgba(107,142,35,", "rgba(255,215,0,", "rgba(255,192,203,", "rgba(106,90,205,", "rgba(173,216,230,", "rgba(238,130,238,", "rgba(152,251,152,", "rgba(70,130,180,", "rgba(244,164,96,", "rgba(210,105,30,", "rgba(220,20,60,"];
var streamingConfetti = false;
var animationTimer = null;
var pause = false;
var lastFrameTime = Date.now();
var particles = [];
var waveAngle = 0;
var context = null;
function getRandomInt(min, max) {
min = Math.ceil(min);
max = Math.floor(max);
return Math.floor(Math.random() * (max - min + 1)) + min;
}
function resetParticle(particle, width, height) {
particle.color = colors[(Math.random() * colors.length) | 0] + (confetti.alpha + ")");
particle.color2 = colors[(Math.random() * colors.length) | 0] + (confetti.alpha + ")");
particle.x = getRandomInt(0, width);
particle.y = getRandomInt(-height / 2, 0);
particle.diameter = Math.random() * 10 + 5;
particle.tilt = Math.random() * 10 - 10;
particle.tiltAngleIncrement = Math.random() * 0.07 + 0.05;
particle.tiltAngle = Math.random() * Math.PI;
return particle;
}
function toggleConfettiPause() {
if (pause)
resumeConfetti();
else
pauseConfetti();
}
function isConfettiPaused() {
return pause;
}
function pauseConfetti() {
pause = true;
}
function resumeConfetti() {
pause = false;
runAnimation();
}
function runAnimation() {
if (pause)
return;
else if (particles.length === 0) {
context.clearRect(0, 0, window.innerWidth, window.innerHeight);
animationTimer = null;
} else {
var now = Date.now();
var delta = now - lastFrameTime;
if (!supportsAnimationFrame || delta > confetti.frameInterval) {
context.clearRect(0, 0, window.innerWidth, window.innerHeight);
updateParticles();
drawParticles(context);
lastFrameTime = now - (delta % confetti.frameInterval);
}
animationTimer = requestAnimationFrame(runAnimation);
}
}
function startConfetti(timeout, min, max) {
var width = window.innerWidth;
var height = window.innerHeight;
window.requestAnimationFrame = (function() {
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
function(callback) {
return window.setTimeout(callback, confetti.frameInterval);
};
})();
var canvas = document.getElementById("confetti-canvas");
if (canvas === null) {
canvas = document.createElement("canvas");
canvas.setAttribute("id", "confetti-canvas");
canvas.setAttribute("style", "display:block;z-index:999999;pointer-events:none;position:fixed;top:0");
document.body.prepend(canvas);
canvas.width = width;
canvas.height = height;
window.addEventListener("resize", function() {
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
}, true);
context = canvas.getContext("2d");
} else if (context === null)
context = canvas.getContext("2d");
var count = confetti.maxCount;
if (min) {
if (max) {
if (min == max)
count = particles.length + max;
else {
if (min > max) {
var temp = min;
min = max;
max = temp;
}
count = particles.length + ((Math.random() * (max - min) + min) | 0);
}
} else
count = particles.length + min;
} else if (max)
count = particles.length + max;
while (particles.length < count)
particles.push(resetParticle({}, width, height));
streamingConfetti = true;
pause = false;
runAnimation();
if (timeout) {
window.setTimeout(stopConfetti, timeout);
}
}
function stopConfetti() {
streamingConfetti = false;
}
function removeConfetti() {
stop();
pause = false;
particles = [];
}
function toggleConfetti() {
if (streamingConfetti)
stopConfetti();
else
startConfetti();
}
function isConfettiRunning() {
return streamingConfetti;
}
function drawParticles(context) {
var particle;
var x, y, x2, y2;
for (var i = 0; i < particles.length; i++) {
particle = particles[i];
particleWidth = particle.diameter;
x2 = particle.x + particle.tilt;
x = x2 + particle.diameter / 2;
y = particle.y;
var svg = new Image();
svg.src = 'https://i.postimg.cc/TPBmVXH1/confetti.png';
context.drawImage(svg, x, y, 20, 40)
/*context.beginPath();
context.lineWidth = particle.diameter;
x2 = particle.x + particle.tilt;
x = x2 + particle.diameter / 2;
y2 = particle.y + particle.tilt + particle.diameter / 2;
if (confetti.gradient) {
var gradient = context.createLinearGradient(x, particle.y, x2, y2);
gradient.addColorStop("0", particle.color);
gradient.addColorStop("1.0", particle.color2);
context.strokeStyle = gradient;
} else
context.strokeStyle = particle.color;
context.moveTo(x, particle.y);
context.lineTo(x2, y2);
context.stroke();*/
}
}
function updateParticles() {
var width = window.innerWidth;
var height = window.innerHeight;
var particle;
waveAngle += 0.01;
for (var i = 0; i < particles.length; i++) {
particle = particles[i];
if (!streamingConfetti && particle.y < -15)
particle.y = height + 100;
else {
particle.tiltAngle += particle.tiltAngleIncrement;
particle.x += Math.sin(waveAngle) - 0.5;
particle.y += (Math.cos(waveAngle) + particle.diameter + confetti.speed) * 0.5;
particle.tilt = Math.sin(particle.tiltAngle) * 15;
}
if (particle.x > width + 20 || particle.x < -20 || particle.y > height) {
if (streamingConfetti && particles.length <= confetti.maxCount)
resetParticle(particle, width, height);
else {
particles.splice(i, 1);
i--;
}
}
}
}
startConfetti(5000, 20, 25)
})();html {
height: 100%;
}
body,
html {
margin: 0;
}
body {
background: black;
}【问题讨论】：
标签： javascript html animation canvas html5-canvas