tools/cc-frame-viewer/src/base/color.js

   1 /* Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2  * Use of this source code is governed by a BSD-style license that can be
   3  * found in the LICENSE file.
   4  */
   5 'use strict';
   6
   7 base.exportTo('base', function() {
   8   function Color(opt_r, opt_g, opt_b, opt_a) {
   9     this.r = Math.floor(opt_r) || 0;
  10     this.g = Math.floor(opt_g) || 0;
  11     this.b = Math.floor(opt_b) || 0;
  12     this.a = opt_a;
  13   }
  14
  15   Color.fromString = function(str) {
  16     var tmp;
  17     var values;
  18     if (str.substr(0, 4) == 'rgb(') {
  19       tmp = str.substr(4, str.length - 5);
  20       values = tmp.split(',').map(function(v) {
  21         return v.replace(/^\s+/, '', 'g');
  22       });
  23       if (values.length != 3)
  24         throw new Error('Malformatted rgb-expression');
  25       return new Color(
  26         parseInt(values[0]),
  27         parseInt(values[1]),
  28         parseInt(values[2]));
  29     } else if (str.substr(0, 4) == 'rgba(') {
  30       tmp = str.substr(5, str.length - 6);
  31       values = tmp.split(',').map(function(v) {
  32         return v.replace(/^\s+/, '', 'g');
  33       });
  34       if (values.length != 3)
  35         throw new Error('Malformatted rgb-expression');
  36       return new Color(
  37         parseInt(values[0]),
  38         parseInt(values[1]),
  39         parseInt(values[2]),
  40         parseFloat(values[3]));
  41     } else if (str[0] == '#' && str.length == 7) {
  42       return new Color(
  43         parseInt(str.substr(1, 2), 16),
  44         parseInt(str.substr(3, 2), 16),
  45         parseInt(str.substr(5, 2), 16));
  46     } else {
  47       throw new Error('Unrecognized string format.');
  48     }
  49   };
  50
  51   Color.lerp = function(a, b, percent) {
  52     if (a.a !== undefined && b.a !== undefined)
  53       return Color.lerpRGBA(a, b, percent);
  54     return Color.lerpRGB(a, b, percent);
  55   }
  56   Color.lerpRGB = function(a, b, percent) {
  57     return new Color(
  58       ((b.r - a.r) * percent) + a.r,
  59       ((b.g - a.g) * percent) + a.g,
  60       ((b.b - a.b) * percent) + a.b);
  61   }
  62
  63   Color.lerpRGBA = function(a, b, percent) {
  64     return new Color(
  65       ((b.r - a.r) * percent) + a.r,
  66       ((b.g - a.g) * percent) + a.g,
  67       ((b.b - a.b) * percent) + a.b,
  68       ((b.a - a.a) * percent) + a.a);
  69   }
  70
  71   Color.prototype = {
  72     brighten: function(opt_k) {
  73       var k;
  74       k = opt_k || 0.45;
  75
  76       return new Color(
  77         Math.min(255, this.r + Math.floor(this.r * k)),
  78         Math.min(255, this.g + Math.floor(this.g * k)),
  79         Math.min(255, this.b + Math.floor(this.b * k)));
  80     },
  81
  82     toString: function() {
  83       if (this.a !== undefined) {
  84         return 'rgba(' +
  85             this.r + ',' + this.g + ',' +
  86             this.b + ',' + this.a + ')';
  87       }
  88       return 'rgb(' + this.r + ',' + this.g + ',' + this.b + ')';
  89     }
  90   };
  91
  92   return {
  93     Color: Color,
  94   }
  95 });
  96