1 ///////////////////////////////////////////////////////////////////////////
2 //
3 // Copyright (c) 2002, Industrial Light & Magic, a division of Lucas
4 // Digital Ltd. LLC
5 //
6 // All rights reserved.
7 //
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9 // modification, are permitted provided that the following conditions are
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12 // notice, this list of conditions and the following disclaimer.
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14 // copyright notice, this list of conditions and the following disclaimer
15 // in the documentation and/or other materials provided with the
16 // distribution.
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20 //
21 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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31 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 //
33 ///////////////////////////////////////////////////////////////////////////
34
35
36 //----------------------------------------------------------------------------
37 //
38 // Implementation of non-template items declared in ImathColorAlgo.h
39 //
40 //----------------------------------------------------------------------------
41
42 #include "ImathColorAlgo.h"
43
44 namespace Imath {
45
46
47 Vec3<double>
hsv2rgb_d(const Vec3<double> & hsv)48 hsv2rgb_d(const Vec3<double> &hsv)
49 {
50 double hue = hsv.x;
51 double sat = hsv.y;
52 double val = hsv.z;
53
54 double x = 0.0, y = 0.0, z = 0.0;
55
56 if (hue == 1) hue = 0;
57 else hue *= 6;
58
59 int i = int(Math<double>::floor(hue));
60 double f = hue-i;
61 double p = val*(1-sat);
62 double q = val*(1-(sat*f));
63 double t = val*(1-(sat*(1-f)));
64
65 switch (i)
66 {
67 case 0: x = val; y = t; z = p; break;
68 case 1: x = q; y = val; z = p; break;
69 case 2: x = p; y = val; z = t; break;
70 case 3: x = p; y = q; z = val; break;
71 case 4: x = t; y = p; z = val; break;
72 case 5: x = val; y = p; z = q; break;
73 }
74
75 return Vec3<double>(x,y,z);
76 }
77
78
79 Color4<double>
hsv2rgb_d(const Color4<double> & hsv)80 hsv2rgb_d(const Color4<double> &hsv)
81 {
82 double hue = hsv.r;
83 double sat = hsv.g;
84 double val = hsv.b;
85
86 double r = 0.0, g = 0.0, b = 0.0;
87
88 if (hue == 1) hue = 0;
89 else hue *= 6;
90
91 int i = int(Math<double>::floor(hue));
92 double f = hue-i;
93 double p = val*(1-sat);
94 double q = val*(1-(sat*f));
95 double t = val*(1-(sat*(1-f)));
96
97 switch (i)
98 {
99 case 0: r = val; g = t; b = p; break;
100 case 1: r = q; g = val; b = p; break;
101 case 2: r = p; g = val; b = t; break;
102 case 3: r = p; g = q; b = val; break;
103 case 4: r = t; g = p; b = val; break;
104 case 5: r = val; g = p; b = q; break;
105 }
106
107 return Color4<double>(r,g,b,hsv.a);
108 }
109
110
111
112 Vec3<double>
rgb2hsv_d(const Vec3<double> & c)113 rgb2hsv_d(const Vec3<double> &c)
114 {
115 const double &x = c.x;
116 const double &y = c.y;
117 const double &z = c.z;
118
119 double max = (x > y) ? ((x > z) ? x : z) : ((y > z) ? y : z);
120 double min = (x < y) ? ((x < z) ? x : z) : ((y < z) ? y : z);
121 double range = max - min;
122 double val = max;
123 double sat = 0;
124 double hue = 0;
125
126 if (max != 0) sat = range/max;
127
128 if (sat != 0)
129 {
130 double h;
131
132 if (x == max) h = (y - z) / range;
133 else if (y == max) h = 2 + (z - x) / range;
134 else h = 4 + (x - y) / range;
135
136 hue = h/6.;
137
138 if (hue < 0.)
139 hue += 1.0;
140 }
141 return Vec3<double>(hue,sat,val);
142 }
143
144
145 Color4<double>
rgb2hsv_d(const Color4<double> & c)146 rgb2hsv_d(const Color4<double> &c)
147 {
148 const double &r = c.r;
149 const double &g = c.g;
150 const double &b = c.b;
151
152 double max = (r > g) ? ((r > b) ? r : b) : ((g > b) ? g : b);
153 double min = (r < g) ? ((r < b) ? r : b) : ((g < b) ? g : b);
154 double range = max - min;
155 double val = max;
156 double sat = 0;
157 double hue = 0;
158
159 if (max != 0) sat = range/max;
160
161 if (sat != 0)
162 {
163 double h;
164
165 if (r == max) h = (g - b) / range;
166 else if (g == max) h = 2 + (b - r) / range;
167 else h = 4 + (r - g) / range;
168
169 hue = h/6.;
170
171 if (hue < 0.)
172 hue += 1.0;
173 }
174 return Color4<double>(hue,sat,val,c.a);
175 }
176
177
178 } // namespace Imath
179