1 files changed, 195 insertions, 0 deletions
diff --git a/basegfx/source/color/bcolortools.cxx b/basegfx/source/color/bcolortools.cxx
new file mode 100644
index 000000000..727b9c781
--- /dev/null
+++ b/basegfx/source/color/bcolortools.cxx
@@ -0,0 +1,195 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <basegfx/numeric/ftools.hxx>
+#include <basegfx/color/bcolor.hxx>
+#include <basegfx/color/bcolortools.hxx>
+#include <rtl/math.hxx>
+
+namespace basegfx::utils
+{
+    BColor rgb2hsl(const BColor& rRGBColor)
+    {
+        const double r=rRGBColor.getRed(), g=rRGBColor.getGreen(), b=rRGBColor.getBlue();
+        const double minVal = std::min( std::min( r, g ), b );
+        const double maxVal = std::max( std::max( r, g ), b );
+        const double d = maxVal - minVal;
+
+        double h=0, s=0, l=0;
+
+        l = (maxVal + minVal) / 2.0;
+
+        if( ::basegfx::fTools::equalZero(d) )
+        {
+            s = h = 0; // hue undefined (achromatic case)
+        }
+        else
+        {
+            s = l > 0.5 ? d/(2.0-maxVal-minVal) :
+                d/(maxVal + minVal);
+
+            if( rtl::math::approxEqual(r, maxVal) )
+                h = (g - b)/d;
+            else if( rtl::math::approxEqual(g, maxVal) )
+                h = 2.0 + (b - r)/d;
+            else
+                h = 4.0 + (r - g)/d;
+
+            h *= 60.0;
+
+            if( h < 0.0 )
+                h += 360.0;
+        }
+
+        return BColor(h,s,l);
+    }
+
+    static double hsl2rgbHelper( double nValue1, double nValue2, double nHue )
+    {
+        // clamp hue to [0,360]
+        nHue = fmod( nHue, 360.0 );
+
+        // cope with wrap-arounds
+        if( nHue < 0.0 )
+            nHue += 360.0;
+
+        if( nHue < 60.0 )
+            return nValue1 + (nValue2 - nValue1)*nHue/60.0;
+        else if( nHue < 180.0 )
+            return nValue2;
+        else if( nHue < 240.0 )
+            return nValue1 + (nValue2 - nValue1)*(240.0 - nHue)/60.0;
+        else
+            return nValue1;
+    }
+
+    BColor hsl2rgb(const BColor& rHSLColor)
+    {
+        const double h=rHSLColor.getRed(), s=rHSLColor.getGreen(), l=rHSLColor.getBlue();
+
+        if( fTools::equalZero(s) )
+            return BColor(l, l, l ); // achromatic case
+
+        const double nVal1( l <= 0.5 ? l*(1.0 + s) : l + s - l*s );
+        const double nVal2( 2.0*l - nVal1 );
+
+        return BColor(
+            hsl2rgbHelper(nVal2,
+                          nVal1,
+                          h + 120.0),
+            hsl2rgbHelper(nVal2,
+                          nVal1,
+                          h),
+            hsl2rgbHelper(nVal2,
+                          nVal1,
+                          h - 120.0) );
+    }
+
+    BColor rgb2hsv(const BColor& rRGBColor)
+    {
+        const double r=rRGBColor.getRed(), g=rRGBColor.getGreen(), b=rRGBColor.getBlue();
+        const double maxVal = std::max(std::max(r,g),b);
+        const double minVal = std::min(std::min(r,g),b);
+        const double delta = maxVal-minVal;
+
+        double h=0, s=0, v=0;
+
+        v = maxVal;
+        if( fTools::equalZero(v) )
+            s = 0;
+        else
+            s = delta / v;
+
+        if( !fTools::equalZero(s) )
+        {
+            if( rtl::math::approxEqual(maxVal, r) )
+            {
+                h = (g - b) / delta;
+            }
+            else if( rtl::math::approxEqual(maxVal, g) )
+            {
+                h = 2.0 + (b - r) / delta;
+            }
+            else
+            {
+                h = 4.0 + (r - g) / delta;
+            }
+
+            h *= 60.0;
+
+            if( h < 0 )
+                h += 360;
+        }
+
+        return BColor(h,s,v);
+    }
+
+    BColor hsv2rgb(const BColor& rHSVColor)
+    {
+        double h=rHSVColor.getRed();
+        const double s=rHSVColor.getGreen(), v=rHSVColor.getBlue();
+
+        if( fTools::equalZero(s) )
+        {
+            // achromatic case: no hue.
+            return BColor(v,v,v);
+        }
+        else
+        {
+            if( fTools::equal(h,360) )
+                h = 0; // 360 degrees is equivalent to 0 degrees
+
+            h /= 60.0;
+            const sal_Int32 intval = static_cast< sal_Int32 >( h );
+            const double f = h - intval;
+            const double p = v*(1.0-s);
+            const double q = v*(1.0-(s*f));
+            const double t = v*(1.0-(s*(1.0-f)));
+
+            /* which hue area? */
+            switch( intval )
+            {
+                case 0:
+                    return BColor(v,t,p);
+
+                case 1:
+                    return BColor(q,v,p);
+
+                case 2:
+                    return BColor(p,v,t);
+
+                case 3:
+                    return BColor(p,q,v);
+
+                case 4:
+                    return BColor(t,p,v);
+
+                case 5:
+                    return BColor(v,p,q);
+
+                default:
+                    // hue overflow
+                    return BColor();
+            }
+        }
+    }
+
+} // end of namespace
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */