我正在尝试将此mousefollow实现到我的网站中：
http://codepen.io/hakimel/pen/KanIi
但我想要自己的自定义颜色而不是默认显示的颜色。我更改了fillcolor值，并且能够更改为一种特定的颜色，但我想要4种不同的颜色。所以我尝试在 fillColor：旁边为此功能添加特定颜色，但没有这样的运气。我还创建了一个fillcolor2：属性，如：
for (var i = 0; i < QUANTITY; i++) {
var particle = {
size: 1,
position: { x: mouseX, y: mouseY },
offset: { x: 0, y: 0 },
shift: { x: mouseX, y: mouseY },
speed: 0.01+Math.random()*0.04,
targetSize: 1,
fillColor: '#bf3e27',
fillColor2: '#1c305c',
orbit: RADIUS*.1 + (RADIUS * .5 * Math.random())
};
并补充说：
context.fillStyle = particle.fillColor2;
context.strokeStyle = particle.fillColor2;
但这也不起作用。我还尝试复制并粘贴相同的js代码，看看它是否可行，只是更改了fillcolor，但它只会显示最后一个粘贴。
有谁能告诉我如何以最简单的方式获得4种不同的颜色，我觉得我非常过于复杂，但很明显是初学者而且对此感到非常沮丧？
最后，我希望4种不同颜色可以跨越不同的半径，并且我使用不同的RADIUS变量进行了混乱，但是如果只有一种颜色，几乎不可能弄清楚如何实现我想要的颜色。因此每种颜色会有4种，我将QUANTITY更改为：
var QUANTITY = 16;
我需要前4个半径为10的半径，所以对于我设置的第一个颜色：
var RADIUS = 10;
理想情况下，我需要前4个颜色（#AAAAAA）半径为10，但需要第二个4为半径10和30之间的颜色（#BBBBBBB），第三个颜色（#CCCCCC）是在半径30-50之间，最后的第四种颜色（#DDDDDD）在50到70之间。
有什么建议吗？
答案 0 :(得分：3)
定义数组中粒子的设置
// I've changed the color for better visibility
var ParticleSettings = [
{color: "#f00", radiusMin: 10, radiusMax: 10},
{color: "#0f0", radiusMin: 10, radiusMax: 30},
{color: "#00f", radiusMin: 30, radiusMax: 50}
];
要获得粒子的正确设置（在本例中为其索引），请使用此函数
function getParticleSettings(particleIndex) {
var settingsIndex = Math.floor(particleIndex / 4) % ParticleSettings.length,
settings = ParticleSettings[settingsIndex];
return {
color: settings.color,
radius: getRandom(settings.radiusMin, settings.radiusMax)
};
}
getRandom只是一个小辅助函数，可以在两个边界之间得到一个随机数
function getRandom(min, max) {
return Math.floor((Math.random() * (max - min)) + min)
}
在createParticle中，我们必须更改for循环以获取当前粒子的设置
for (var i = 0; i < QUANTITY; i++) {
// get the settings for the current particle
var particleSettings = getParticleSettings(i);
var particle = {
size: 1,
position: { x: mouseX, y: mouseY },
offset: { x: 0, y: 0 },
shift: { x: mouseX, y: mouseY },
speed: 0.01+Math.random()*0.04,
targetSize: 1,
fillColor: particleSettings.color, // <--
orbit: particleSettings.radius // <--
};
particles.push( particle );
}
This将是上述更改的结果。
答案 1 :(得分：3)
您可以将QUANTITY，COLOR和RADIUS的定义替换为这些数组的定义，同时定义RADIUS的范围：
var GROUPS = [
{
QUANTITY: 4,
RADIUS: [ 5, 10],
COLOR: 0x888888
},
{
QUANTITY: 4,
RADIUS: [10, 30],
COLOR: 0xAA80AA
},
{
QUANTITY: 4,
RADIUS: [30, 50],
COLOR: 0xA0A0CC
},
{
QUANTITY: 4,
RADIUS: [50, 70],
COLOR: 0xFFE0E0
}
];
然后在createParticles函数内部迭代GROUPS：
for (var g = 0; g < GROUPS.length; g++) {
var attribs = GROUPS[g];
for (var i = 0; i < attribs.QUANTITY; i++) {
var particle = {
size: 1,
position: { x: mouseX, y: mouseY },
offset: { x: 0, y: 0 },
shift: { x: mouseX, y: mouseY },
speed: 0.01+Math.random()*0.04,
targetSize: 1,
fillColor: '#' + attribs.COLOR.toString(16),
orbit: attribs.RADIUS[0] +
(attribs.RADIUS[1]-attribs.RADIUS[0]) * Math.random()
};
particles.push( particle );
}
}
这是一个片段：
// One of my first <canvas> experiments, woop! :D
var SCREEN_WIDTH = window.innerWidth;
var SCREEN_HEIGHT = window.innerHeight;
var GROUPS = [
{
QUANTITY: 4,
RADIUS: [ 5, 10],
COLOR: 0x888888
},
{
QUANTITY: 4,
RADIUS: [10, 30],
COLOR: 0xAA80AA
},
{
QUANTITY: 4,
RADIUS: [30, 50],
COLOR: 0xA0A0CC
},
{
QUANTITY: 4,
RADIUS: [50, 70],
COLOR: 0xFFE0E0
}
];
var RADIUS_SCALE = 1;
var RADIUS_SCALE_MIN = 1;
var RADIUS_SCALE_MAX = 1.5;
var canvas;
var context;
var particles;
var mouseX = SCREEN_WIDTH * 0.5;
var mouseY = SCREEN_HEIGHT * 0.5;
var mouseIsDown = false;
function init() {
canvas = document.getElementById( 'world' );
if (canvas && canvas.getContext) {
context = canvas.getContext('2d');
// Register event listeners
window.addEventListener('mousemove', documentMouseMoveHandler, false);
window.addEventListener('mousedown', documentMouseDownHandler, false);
window.addEventListener('mouseup', documentMouseUpHandler, false);
document.addEventListener('touchstart', documentTouchStartHandler, false);
document.addEventListener('touchmove', documentTouchMoveHandler, false);
window.addEventListener('resize', windowResizeHandler, false);
createParticles();
windowResizeHandler();
setInterval( loop, 1000 / 60 );
}
}
function createParticles() {
particles = [];
for (var g = 0; g < GROUPS.length; g++) {
var attribs = GROUPS[g];
for (var i = 0; i < attribs.QUANTITY; i++) {
var particle = {
size: 1,
position: { x: mouseX, y: mouseY },
offset: { x: 0, y: 0 },
shift: { x: mouseX, y: mouseY },
speed: 0.01+Math.random()*0.04,
targetSize: 1,
fillColor: '#' + attribs.COLOR.toString(16),
orbit: attribs.RADIUS[0] +
(attribs.RADIUS[1]-attribs.RADIUS[0]) * Math.random()
};
particles.push( particle );
}
}
}
function documentMouseMoveHandler(event) {
mouseX = event.clientX - (window.innerWidth - SCREEN_WIDTH) * .5;
mouseY = event.clientY - (window.innerHeight - SCREEN_HEIGHT) * .5;
}
function documentMouseDownHandler(event) {
mouseIsDown = true;
}
function documentMouseUpHandler(event) {
mouseIsDown = false;
}
function documentTouchStartHandler(event) {
if(event.touches.length == 1) {
event.preventDefault();
mouseX = event.touches[0].pageX - (window.innerWidth - SCREEN_WIDTH) * .5;;
mouseY = event.touches[0].pageY - (window.innerHeight - SCREEN_HEIGHT) * .5;
}
}
function documentTouchMoveHandler(event) {
if(event.touches.length == 1) {
event.preventDefault();
mouseX = event.touches[0].pageX - (window.innerWidth - SCREEN_WIDTH) * .5;;
mouseY = event.touches[0].pageY - (window.innerHeight - SCREEN_HEIGHT) * .5;
}
}
function windowResizeHandler() {
SCREEN_WIDTH = window.innerWidth;
SCREEN_HEIGHT = window.innerHeight;
canvas.width = SCREEN_WIDTH;
canvas.height = SCREEN_HEIGHT;
}
function loop() {
if( mouseIsDown ) {
RADIUS_SCALE += ( RADIUS_SCALE_MAX - RADIUS_SCALE ) * (0.02);
}
else {
RADIUS_SCALE -= ( RADIUS_SCALE - RADIUS_SCALE_MIN ) * (0.02);
}
RADIUS_SCALE = Math.min( RADIUS_SCALE, RADIUS_SCALE_MAX );
context.fillStyle = 'rgba(0,0,0,0.05)';
context.fillRect(0, 0, context.canvas.width, context.canvas.height);
for (i = 0, len = particles.length; i < len; i++) {
var particle = particles[i];
var lp = { x: particle.position.x, y: particle.position.y };
// Rotation
particle.offset.x += particle.speed;
particle.offset.y += particle.speed;
// Follow mouse with some lag
particle.shift.x += ( mouseX - particle.shift.x) * (particle.speed);
particle.shift.y += ( mouseY - particle.shift.y) * (particle.speed);
// Apply position
particle.position.x = particle.shift.x + Math.cos(i + particle.offset.x) * (particle.orbit*RADIUS_SCALE);
particle.position.y = particle.shift.y + Math.sin(i + particle.offset.y) * (particle.orbit*RADIUS_SCALE);
// Limit to screen bounds
particle.position.x = Math.max( Math.min( particle.position.x, SCREEN_WIDTH ), 0 );
particle.position.y = Math.max( Math.min( particle.position.y, SCREEN_HEIGHT ), 0 );
particle.size += ( particle.targetSize - particle.size ) * 0.05;
if( Math.round( particle.size ) == Math.round( particle.targetSize ) ) {
particle.targetSize = 1 + Math.random() * 7;
}
context.beginPath();
context.fillStyle = particle.fillColor;
context.strokeStyle = particle.fillColor;
context.lineWidth = particle.size;
context.moveTo(lp.x, lp.y);
context.lineTo(particle.position.x, particle.position.y);
context.stroke();
context.arc(particle.position.x, particle.position.y, particle.size/2, 0, Math.PI*2, true);
context.fill();
}
}
window.onload = init;body {
background-color: #000000;
padding: 0;
margin: 0;
overflow: hidden;
}<canvas id='world'></canvas>
答案 2 :(得分：0)
您可以定义数组中的颜色，因为您使用的是for循环，您可以将它们编入索引：
var colors = ['#AAAAAA', '#BBBBBB', '#CCCCCC', '#DDDDDD'];
var particle = {
...
fillColor: colors[i],
...
}
现在这只适用于前四种颜色，但由于您声明数量为16，因此您可以使用2 for次循环来实现此目的。像这样：
//will run 16 times
for(var i = 0; i < QUANTITY; i++) {
for(var x = 0; x < 4; x++) {
var particle = {
//note that i'm using x here since the array has only 4 keys.
fillColor: colors[x];
}
}
}