[英]HTML5 Gradient: changing color of gradient changes color of triangle on a canvas
[英]changing color in terms of gradient html5 canvas
这种变化只是线性变化。
所以给定两种颜色
var rgb1 = [100,200,10];
var rgb2 = [200,10,100];
时间t在0到1范围内的颜色
var colour = [
((rgb2[0] - rgb1[0]) * t + rgb1[0]) | 0, // the | 0 floors the value
((rgb2[1] - rgb1[1]) * t + rgb1[1]) | 0,
((rgb2[2] - rgb1[2]) * t + rgb1[2]) | 0,
]
如果您有绝对时间(以毫秒为单位),则可以按如下所示转换为归一化的t(0-1)
// do at start of time
startTime = performance.now();
endTime = performance.now() + 10000; // in ten seconds
// for each update
t = (performance.now() - startTime) / (endTime - startTime);
t = t > 1 ? 1 : t; // make sure you dont go past the end
// get the color
var colour = [
((rgb2[0] - rgb1[0]) * t + rgb1[0]) | 0, // the | 0 floors the value
((rgb2[1] - rgb1[1]) * t + rgb1[1]) | 0,
((rgb2[2] - rgb1[2]) * t + rgb1[2]) | 0,
]
// as a CSS colour
var cssColour = "rgb(" + colour[0] + "," + colour[1] + "," + colour[2] + ")";
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.