Cycles / Wavelength to RGB node:
[blender.git] / intern / cycles / util / util_color.h
index 5136ea5c5db582919b8aebd210b2886d9307c3b5..0de29371899721ba43a844f213ba431c446fea37 100644 (file)
@@ -40,6 +40,100 @@ __device float color_scene_linear_to_srgb(float c)
                return 1.055f * powf(c, 1.0f / 2.4f) - 0.055f;
 }
 
+__device float3 rgb_to_hsv(float3 rgb)
+{
+       float cmax, cmin, h, s, v, cdelta;
+       float3 c;
+
+       cmax = fmaxf(rgb.x, fmaxf(rgb.y, rgb.z));
+       cmin = min(rgb.x, min(rgb.y, rgb.z));
+       cdelta = cmax - cmin;
+
+       v = cmax;
+
+       if(cmax != 0.0f) {
+               s = cdelta/cmax;
+       }
+       else {
+               s = 0.0f;
+               h = 0.0f;
+       }
+
+       if(s == 0.0f) {
+               h = 0.0f;
+       }
+       else {
+               float3 cmax3 = make_float3(cmax, cmax, cmax);
+               c = (cmax3 - rgb)/cdelta;
+
+               if(rgb.x == cmax) h = c.z - c.y;
+               else if(rgb.y == cmax) h = 2.0f + c.x -  c.z;
+               else h = 4.0f + c.y - c.x;
+
+               h /= 6.0f;
+
+               if(h < 0.0f)
+                       h += 1.0f;
+       }
+
+       return make_float3(h, s, v);
+}
+
+__device float3 hsv_to_rgb(float3 hsv)
+{
+       float i, f, p, q, t, h, s, v;
+       float3 rgb;
+
+       h = hsv.x;
+       s = hsv.y;
+       v = hsv.z;
+
+       if(s == 0.0f) {
+               rgb = make_float3(v, v, v);
+       }
+       else {
+               if(h == 1.0f)
+                       h = 0.0f;
+               
+               h *= 6.0f;
+               i = floorf(h);
+               f = h - i;
+               rgb = make_float3(f, f, f);
+               p = v*(1.0f-s);
+               q = v*(1.0f-(s*f));
+               t = v*(1.0f-(s*(1.0f-f)));
+               
+               if(i == 0.0f) rgb = make_float3(v, t, p);
+               else if(i == 1.0f) rgb = make_float3(q, v, p);
+               else if(i == 2.0f) rgb = make_float3(p, v, t);
+               else if(i == 3.0f) rgb = make_float3(p, q, v);
+               else if(i == 4.0f) rgb = make_float3(t, p, v);
+               else rgb = make_float3(v, p, q);
+       }
+
+       return rgb;
+}
+
+__device float3 xyY_to_xyz(float x, float y, float Y)
+{
+       float X, Z;
+
+       if(y != 0.0f) X = (x / y) * Y;
+       else X = 0.0f;
+
+       if(y != 0.0f && Y != 0.0f) Z = (1.0f - x - y) / y * Y;
+       else Z = 0.0f;
+
+       return make_float3(X, Y, Z);
+}
+
+__device float3 xyz_to_rgb(float x, float y, float z)
+{
+       return make_float3(3.240479f * x + -1.537150f * y + -0.498535f * z,
+                                         -0.969256f * x +  1.875991f * y +  0.041556f * z,
+                                          0.055648f * x + -0.204043f * y +  1.057311f * z);
+}
+
 #ifndef __KERNEL_OPENCL__
 
 __device float3 color_srgb_to_scene_linear(float3 c)