source/libs/poppler/poppler-src/splash/SplashScreen.h

   1 //========================================================================
   2 //
   3 // SplashScreen.h
   4 //
   5 //========================================================================
   6
   7 //========================================================================
   8 //
   9 // Modified under the Poppler project - http://poppler.freedesktop.org
  10 //
  11 // All changes made under the Poppler project to this file are licensed
  12 // under GPL version 2 or later
  13 //
  14 // Copyright (C) 2009 Albert Astals Cid <aacid@kde.org>
  15 //
  16 // To see a description of the changes please see the Changelog file that
  17 // came with your tarball or type make ChangeLog if you are building from git
  18 //
  19 //========================================================================
  20
  21 #ifndef SPLASHSCREEN_H
  22 #define SPLASHSCREEN_H
  23
  24 #ifdef USE_GCC_PRAGMAS
  25 #pragma interface
  26 #endif
  27
  28 #include "SplashTypes.h"
  29
  30 #include <stdlib.h>
  31
  32 //------------------------------------------------------------------------
  33 // SplashScreen
  34 //------------------------------------------------------------------------
  35
  36 class SplashScreen {
  37 public:
  38
  39   SplashScreen(SplashScreenParams *params);
  40   SplashScreen(SplashScreen *screen);
  41   ~SplashScreen();
  42
  43   SplashScreen *copy() { return new SplashScreen(this); }
  44
  45   // Return the computed pixel value (0=black, 1=white) for the gray
  46   // level <value> at (<x>, <y>).
  47   int test(int x, int y, Guchar value) {
  48     int xx, yy;
  49     if (mat == NULL) createMatrix();
  50     xx = x & sizeM1;
  51     yy = y & sizeM1;
  52     return value < mat[(yy << log2Size) + xx] ? 0 : 1;
  53   }
  54
  55   // Returns true if value is above the white threshold or below the
  56   // black threshold, i.e., if the corresponding halftone will be
  57   // solid white or black.
  58   GBool isStatic(Guchar value) { if (mat == NULL) createMatrix(); return value < minVal || value >= maxVal; }
  59
  60 private:
  61   void createMatrix();
  62
  63   void buildDispersedMatrix(int i, int j, int val,
  64                             int delta, int offset);
  65   void buildClusteredMatrix();
  66   int distance(int x0, int y0, int x1, int y1);
  67   void buildSCDMatrix(int r);
  68
  69   SplashScreenParams *screenParams;     // params to create the other members
  70   Guchar *mat;                  // threshold matrix
  71   int size;                     // size of the threshold matrix
  72   int sizeM1;                   // size - 1
  73   int log2Size;                 // log2(size)
  74   Guchar minVal;                // any pixel value below minVal generates
  75                                 //   solid black
  76   Guchar maxVal;                // any pixel value above maxVal generates
  77                                 //   solid white
  78 };
  79
  80 #endif