diff options
Diffstat (limited to 'intern/cycles/util/color.h')
-rw-r--r-- | intern/cycles/util/color.h | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/intern/cycles/util/color.h b/intern/cycles/util/color.h index cccccde3ba6..a390b49cf7b 100644 --- a/intern/cycles/util/color.h +++ b/intern/cycles/util/color.h @@ -152,6 +152,55 @@ ccl_device float3 hsv_to_rgb(float3 hsv) return rgb; } +ccl_device float3 rgb_to_hsl(float3 rgb) +{ + float cmax, cmin, h, s, l; + + cmax = fmaxf(rgb.x, fmaxf(rgb.y, rgb.z)); + cmin = min(rgb.x, min(rgb.y, rgb.z)); + l = min(1.0f, (cmax + cmin) / 2.0f); + + if (cmax == cmin) { + h = s = 0.0f; /* achromatic */ + } else { + float cdelta = cmax - cmin; + s = l > 0.5f ? cdelta / (2.0f - cmax - cmin) : cdelta / (cmax + cmin); + if (cmax == rgb.x) { + h = (rgb.y - rgb.z) / cdelta + (rgb.y < rgb.z ? 6.0f : 0.0f); + } + else if (cmax == rgb.y) { + h = (rgb.z - rgb.x) / cdelta + 2.0f; + } + else { + h = (rgb.x - rgb.y) / cdelta + 4.0f; + } + } + h /= 6.0f; + + return make_float3(h, s, l); +} + +ccl_device float3 hsl_to_rgb(float3 hsl) +{ + float nr, ng, nb, chroma, h, s, l; + + h = hsl.x; + s = hsl.y; + l = hsl.z; + + nr = fabsf(h * 6.0f - 3.0f) - 1.0f; + ng = 2.0f - fabsf(h * 6.0f - 2.0f); + nb = 2.0f - fabsf(h * 6.0f - 4.0f); + + nr = clamp(nr, 0.0f, 1.0f); + nb = clamp(nb, 0.0f, 1.0f); + ng = clamp(ng, 0.0f, 1.0f); + + chroma = (1.0f - fabsf(2.0f * l - 1.0f)) * s; + + return make_float3((nr - 0.5f) * chroma + l, (ng - 0.5f) * chroma + l, (nb - 0.5f) * chroma + l); +} + ccl_device float3 xyY_to_xyz(float x, float y, float Y) { float X, Z; |