poppler/GfxState_helpers.h

//========================================================================
//
// GfxState.cc
//
// Copyright 1996-2003 Glyph & Cog, LLC
//
//========================================================================

//========================================================================
//
// Modified under the Poppler project - http://poppler.freedesktop.org
//
// All changes made under the Poppler project to this file are licensed
// under GPL version 2 or later
//
// Copyright (C) 2009, 2011 Albert Astals Cid <aacid@kde.org>
//
// To see a description of the changes please see the Changelog file that
// came with your tarball or type make ChangeLog if you are building from git
//
//========================================================================

#include "GfxState.h"

static inline GfxColorComp clip01(GfxColorComp x) {
  return (x < 0) ? 0 : (x > gfxColorComp1) ? gfxColorComp1 : x;
}

static inline double clip01(double x) {
  return (x < 0) ? 0 : (x > 1) ? 1 : x;
}

static inline void cmykToRGBMatrixMultiplication(const double &c, const double &m, const double &y, const double &k, const double &c1, const double &m1, const double &y1, const double &k1, double &r, double &g, double &b)
{
  double x;
  // this is a matrix multiplication, unrolled for performance
  //                        C M Y K
  x = c1 * m1 * y1 * k1; // 0 0 0 0
  r = g = b = x;
  x = c1 * m1 * y1 * k;  // 0 0 0 1
  r += 0.1373 * x;
  g += 0.1216 * x;
  b += 0.1255 * x;
  x = c1 * m1 * y  * k1; // 0 0 1 0
  r += x;
  g += 0.9490 * x;
  x = c1 * m1 * y  * k;  // 0 0 1 1
  r += 0.1098 * x;
  g += 0.1020 * x;
  x = c1 * m  * y1 * k1; // 0 1 0 0
  r += 0.9255 * x;
  b += 0.5490 * x;
  x = c1 * m  * y1 * k;  // 0 1 0 1
  r += 0.1412 * x;
  x = c1 * m  * y  * k1; // 0 1 1 0
  r += 0.9294 * x;
  g += 0.1098 * x;
  b += 0.1412 * x;
  x = c1 * m  * y  * k;  // 0 1 1 1
  r += 0.1333 * x;
  x = c  * m1 * y1 * k1; // 1 0 0 0
  g += 0.6784 * x;
  b += 0.9373 * x;
  x = c  * m1 * y1 * k;  // 1 0 0 1
  g += 0.0588 * x;
  b += 0.1412 * x;
  x = c  * m1 * y  * k1; // 1 0 1 0
  g += 0.6510 * x;
  b += 0.3137 * x;
  x = c  * m1 * y  * k;  // 1 0 1 1
  g += 0.0745 * x;
  x = c  * m  * y1 * k1; // 1 1 0 0
  r += 0.1804 * x;
  g += 0.1922 * x;
  b += 0.5725 * x;
  x = c  * m  * y1 * k;  // 1 1 0 1
  b += 0.0078 * x;
  x = c  * m  * y  * k1; // 1 1 1 0
  r += 0.2118 * x;
  g += 0.2119 * x;
  b += 0.2235 * x;
}