如何将此计算更改为较暗而不是较亮的颜色?Javascript计算较暗的颜色
function increase_brightness(hex, percent){
// strip the leading # if it's there
hex = hex.replace(/^\s*#|\s*$/g, '');
// convert 3 char codes --> 6, e.g. `E0F` --> `EE00FF`
if(hex.length == 3){
hex = hex.replace(/(.)/g, '$1$1');
}
var r = parseInt(hex.substr(0, 2), 16),
g = parseInt(hex.substr(2, 2), 16),
b = parseInt(hex.substr(4, 2), 16);
return '#' +
((0|(1<<8) + r + (256 - r) * percent/100).toString(16)).substr(1) +
((0|(1<<8) + g + (256 - g) * percent/100).toString(16)).substr(1) +
((0|(1<<8) + b + (256 - b) * percent/100).toString(16)).substr(1);
}
SRC = JavaScript Calculate brighter colour
演示http://jsbin.com/utavax/3/edit
您是否试图与一个负的百分比? –