diff options
Diffstat (limited to 'indra/llmath/v3color.cpp')
| -rw-r--r-- | indra/llmath/v3color.cpp | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/indra/llmath/v3color.cpp b/indra/llmath/v3color.cpp index 2dbc368d98..d85006fa9c 100644 --- a/indra/llmath/v3color.cpp +++ b/indra/llmath/v3color.cpp @@ -42,3 +42,52 @@ std::ostream& operator<<(std::ostream& s, const LLColor3 &a) s << "{ " << a.mV[VX] << ", " << a.mV[VY] << ", " << a.mV[VZ] << " }"; return s; } + +void LLColor3::calcHSL(F32* hue, F32* saturation, F32* luminance) const +{ + F32 var_R = mV[VRED]; + F32 var_G = mV[VGREEN]; + F32 var_B = mV[VBLUE]; + + F32 var_Min = ( var_R < ( var_G < var_B ? var_G : var_B ) ? var_R : ( var_G < var_B ? var_G : var_B ) ); + F32 var_Max = ( var_R > ( var_G > var_B ? var_G : var_B ) ? var_R : ( var_G > var_B ? var_G : var_B ) ); + + F32 del_Max = var_Max - var_Min; + + F32 L = ( var_Max + var_Min ) / 2.0f; + F32 H = 0.0f; + F32 S = 0.0f; + + if ( del_Max == 0.0f ) + { + H = 0.0f; + S = 0.0f; + } + else + { + if ( L < 0.5 ) + S = del_Max / ( var_Max + var_Min ); + else + S = del_Max / ( 2.0f - var_Max - var_Min ); + + F32 del_R = ( ( ( var_Max - var_R ) / 6.0f ) + ( del_Max / 2.0f ) ) / del_Max; + F32 del_G = ( ( ( var_Max - var_G ) / 6.0f ) + ( del_Max / 2.0f ) ) / del_Max; + F32 del_B = ( ( ( var_Max - var_B ) / 6.0f ) + ( del_Max / 2.0f ) ) / del_Max; + + if ( var_R >= var_Max ) + H = del_B - del_G; + else + if ( var_G >= var_Max ) + H = ( 1.0f / 3.0f ) + del_R - del_B; + else + if ( var_B >= var_Max ) + H = ( 2.0f / 3.0f ) + del_G - del_R; + + if ( H < 0.0f ) H += 1.0f; + if ( H > 1.0f ) H -= 1.0f; + } + + if (hue) *hue = H; + if (saturation) *saturation = S; + if (luminance) *luminance = L; +}
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