Jamie Gennis | 66a3768 | 2013-07-15 18:29:18 -0700 | [diff] [blame] | 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 | /** |
| 8 | * @fileoverview 2D bounding box computations. |
| 9 | */ |
| 10 | base.require('base.gl_matrix'); |
| 11 | base.require('base.rect'); |
| 12 | |
| 13 | base.exportTo('base', function() { |
| 14 | |
| 15 | /** |
| 16 | * Tracks a 2D bounding box. |
| 17 | * @constructor |
| 18 | */ |
| 19 | function BBox2() { |
| 20 | this.isEmpty_ = true; |
| 21 | this.min_ = undefined; |
| 22 | this.max_ = undefined; |
| 23 | }; |
| 24 | |
| 25 | BBox2.prototype = { |
| 26 | __proto__: Object.prototype, |
| 27 | |
| 28 | reset: function() { |
| 29 | this.isEmpty_ = true; |
| 30 | this.min_ = undefined; |
| 31 | this.max_ = undefined; |
| 32 | }, |
| 33 | |
| 34 | get isEmpty() { |
| 35 | return this.isEmpty_; |
| 36 | }, |
| 37 | |
| 38 | addBBox2: function(bbox2) { |
| 39 | if (bbox2.isEmpty) |
| 40 | return; |
| 41 | this.addVec2(bbox2.min_); |
| 42 | this.addVec2(bbox2.max_); |
| 43 | }, |
| 44 | |
| 45 | clone: function() { |
| 46 | var bbox = new BBox2(); |
| 47 | bbox.addBBox2(this); |
| 48 | return bbox; |
| 49 | }, |
| 50 | |
| 51 | /** |
| 52 | * Adds x, y to the range. |
| 53 | */ |
| 54 | addXY: function(x, y) { |
| 55 | if (this.isEmpty_) { |
| 56 | this.max_ = vec2.create(); |
| 57 | this.min_ = vec2.create(); |
| 58 | vec2.set(this.max_, x, y); |
| 59 | vec2.set(this.min_, x, y); |
| 60 | this.isEmpty_ = false; |
| 61 | return; |
| 62 | } |
| 63 | this.max_[0] = Math.max(this.max_[0], x); |
| 64 | this.max_[1] = Math.max(this.max_[1], y); |
| 65 | this.min_[0] = Math.min(this.min_[0], x); |
| 66 | this.min_[1] = Math.min(this.min_[1], y); |
| 67 | }, |
| 68 | |
| 69 | /** |
| 70 | * Adds value_x, value_y in the form [value_x,value_y] to the range. |
| 71 | */ |
| 72 | addVec2: function(value) { |
| 73 | if (this.isEmpty_) { |
| 74 | this.max_ = vec2.create(); |
| 75 | this.min_ = vec2.create(); |
| 76 | vec2.set(this.max_, value[0], value[1]); |
| 77 | vec2.set(this.min_, value[0], value[1]); |
| 78 | this.isEmpty_ = false; |
| 79 | return; |
| 80 | } |
| 81 | this.max_[0] = Math.max(this.max_[0], value[0]); |
| 82 | this.max_[1] = Math.max(this.max_[1], value[1]); |
| 83 | this.min_[0] = Math.min(this.min_[0], value[0]); |
| 84 | this.min_[1] = Math.min(this.min_[1], value[1]); |
| 85 | }, |
| 86 | |
| 87 | addQuad: function(quad) { |
| 88 | this.addVec2(quad.p1); |
| 89 | this.addVec2(quad.p2); |
| 90 | this.addVec2(quad.p3); |
| 91 | this.addVec2(quad.p4); |
| 92 | }, |
| 93 | |
| 94 | get minVec2() { |
| 95 | if (this.isEmpty_) |
| 96 | return undefined; |
| 97 | return this.min_; |
| 98 | }, |
| 99 | |
| 100 | get maxVec2() { |
| 101 | if (this.isEmpty_) |
| 102 | return undefined; |
| 103 | return this.max_; |
| 104 | }, |
| 105 | |
| 106 | get sizeAsVec2() { |
| 107 | if (this.isEmpty_) |
| 108 | throw new Error('Empty BBox2 has no size'); |
| 109 | var size = vec2.create(); |
| 110 | vec2.subtract(size, this.max_, this.min_); |
| 111 | return size; |
| 112 | }, |
| 113 | |
| 114 | get size() { |
| 115 | if (this.isEmpty_) |
| 116 | throw new Error('Empty BBox2 has no size'); |
| 117 | return {width: this.max_[0] - this.min_[0], |
| 118 | height: this.max_[1] - this.min_[1]}; |
| 119 | }, |
| 120 | |
| 121 | get width() { |
| 122 | if (this.isEmpty_) |
| 123 | throw new Error('Empty BBox2 has no width'); |
| 124 | return this.max_[0] - this.min_[0]; |
| 125 | }, |
| 126 | |
| 127 | get height() { |
| 128 | if (this.isEmpty_) |
| 129 | throw new Error('Empty BBox2 has no width'); |
| 130 | return this.max_[1] - this.min_[1]; |
| 131 | }, |
| 132 | |
| 133 | toString: function() { |
| 134 | if (this.isEmpty_) |
| 135 | return 'empty'; |
| 136 | return 'min=(' + this.min_[0] + ',' + this.min_[1] + ') ' + |
| 137 | 'max=(' + this.max_[0] + ',' + this.max_[1] + ')'; |
| 138 | }, |
| 139 | |
| 140 | asRect: function() { |
| 141 | return base.Rect.FromXYWH( |
| 142 | this.min_[0], |
| 143 | this.min_[1], |
| 144 | this.max_[0] - this.min_[0], |
| 145 | this.max_[1] - this.min_[1]); |
| 146 | } |
| 147 | }; |
| 148 | |
| 149 | return { |
| 150 | BBox2: BBox2 |
| 151 | }; |
| 152 | |
| 153 | }); |