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diff --git a/agg/inc/agg_gamma_lut.h b/agg/inc/agg_gamma_lut.h
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+//----------------------------------------------------------------------------
+// Anti-Grain Geometry - Version 2.3
+// Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
+//
+// Permission to copy, use, modify, sell and distribute this software
+// is granted provided this copyright notice appears in all copies.
+// This software is provided "as is" without express or implied
+// warranty, and with no claim as to its suitability for any purpose.
+//
+//----------------------------------------------------------------------------
+// Contact: mcseem@antigrain.com
+// mcseemagg@yahoo.com
+// http://www.antigrain.com
+//----------------------------------------------------------------------------
+
+#ifndef AGG_GAMMA_LUT_INCLUDED
+#define AGG_GAMMA_LUT_INCLUDED
+
+#include <math.h>
+#include "agg_basics.h"
+
+namespace agg
+{
+ template<class LoResT=int8u,
+ class HiResT=int8u,
+ unsigned GammaShift=8,
+ unsigned HiResShift=8> class gamma_lut
+ {
+ public:
+ enum
+ {
+ gamma_shift = GammaShift,
+ gamma_size = 1 << gamma_shift,
+ gamma_mask = gamma_size - 1
+ };
+
+ enum
+ {
+ hi_res_shift = HiResShift,
+ hi_res_size = 1 << hi_res_shift,
+ hi_res_mask = hi_res_size - 1
+ };
+
+ ~gamma_lut()
+ {
+ delete [] m_inv_gamma;
+ delete [] m_dir_gamma;
+ }
+
+ gamma_lut() :
+ m_gamma(1.0),
+ m_dir_gamma(new HiResT[gamma_size]),
+ m_inv_gamma(new LoResT[hi_res_size])
+ {
+ unsigned i;
+ for(i = 0; i < gamma_size; i++)
+ {
+ m_dir_gamma[i] = HiResT(i << (hi_res_shift - gamma_shift));
+ }
+
+ for(i = 0; i < hi_res_size; i++)
+ {
+ m_inv_gamma[i] = LoResT(i >> (hi_res_shift - gamma_shift));
+ }
+ }
+
+ gamma_lut(double g) :
+ m_gamma(1.0),
+ m_dir_gamma(new HiResT[gamma_size]),
+ m_inv_gamma(new LoResT[hi_res_size])
+ {
+ gamma(g);
+ }
+
+ void gamma(double g)
+ {
+ m_gamma = g;
+
+ unsigned i;
+ for(i = 0; i < gamma_size; i++)
+ {
+ m_dir_gamma[i] = (HiResT)(pow(double(i) / double(gamma_mask), m_gamma) * double(hi_res_mask) + 0.5);
+ }
+
+ double inv_g = 1.0 / g;
+ for(i = 0; i < hi_res_size; i++)
+ {
+ m_inv_gamma[i] = (LoResT)(pow(double(i) / double(hi_res_mask), inv_g) * double(gamma_mask) + 0.5);
+ }
+ }
+
+ double gamma() const
+ {
+ return m_gamma;
+ }
+
+ HiResT dir(LoResT v) const
+ {
+ return m_dir_gamma[unsigned(v)];
+ }
+
+ LoResT inv(HiResT v) const
+ {
+ return m_inv_gamma[unsigned(v)];
+ }
+
+ private:
+ double m_gamma;
+ HiResT* m_dir_gamma;
+ LoResT* m_inv_gamma;
+ };
+}
+
+#endif