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

   1 //========================================================================
   2 //
   3 // SplashClip.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) 2010 Albert Astals Cid <aacid@kde.org>
  15 // Copyright (C) 2013 Thomas Freitag <Thomas.Freitag@alfa.de>
  16 //
  17 // To see a description of the changes please see the Changelog file that
  18 // came with your tarball or type make ChangeLog if you are building from git
  19 //
  20 //========================================================================
  21
  22 #ifndef SPLASHCLIP_H
  23 #define SPLASHCLIP_H
  24
  25 #ifdef USE_GCC_PRAGMAS
  26 #pragma interface
  27 #endif
  28
  29 #include "SplashTypes.h"
  30 #include "SplashMath.h"
  31 #include "SplashXPathScanner.h"
  32
  33 class SplashPath;
  34 class SplashXPath;
  35 class SplashBitmap;
  36
  37 //------------------------------------------------------------------------
  38
  39 enum SplashClipResult {
  40   splashClipAllInside,
  41   splashClipAllOutside,
  42   splashClipPartial
  43 };
  44
  45 //------------------------------------------------------------------------
  46 // SplashClip
  47 //------------------------------------------------------------------------
  48
  49 class SplashClip {
  50 public:
  51
  52   // Create a clip, for the given rectangle.
  53   SplashClip(SplashCoord x0, SplashCoord y0,
  54              SplashCoord x1, SplashCoord y1,
  55              GBool antialiasA);
  56
  57   // Copy a clip.
  58   SplashClip *copy() { return new SplashClip(this); }
  59
  60   ~SplashClip();
  61
  62   // Reset the clip to a rectangle.
  63   void resetToRect(SplashCoord x0, SplashCoord y0,
  64                    SplashCoord x1, SplashCoord y1);
  65
  66   // Intersect the clip with a rectangle.
  67   SplashError clipToRect(SplashCoord x0, SplashCoord y0,
  68                          SplashCoord x1, SplashCoord y1);
  69
  70   // Interesect the clip with <path>.
  71   SplashError clipToPath(SplashPath *path, SplashCoord *matrix,
  72                          SplashCoord flatness, GBool eo);
  73
  74   // Returns true if (<x>,<y>) is inside the clip.
  75   GBool test(int x, int y)
  76   {
  77     int i;
  78
  79     // check the rectangle
  80     if (x < xMinI || x > xMaxI || y < yMinI || y > yMaxI) {
  81       return gFalse;
  82     }
  83
  84     // check the paths
  85     if (antialias) {
  86       for (i = 0; i < length; ++i) {
  87         if (!scanners[i]->test(x * splashAASize, y * splashAASize)) {
  88           return gFalse;
  89         }
  90       }
  91     } else {
  92       for (i = 0; i < length; ++i) {
  93         if (!scanners[i]->test(x, y)) {
  94           return gFalse;
  95         }
  96       }
  97     }
  98
  99     return gTrue;
 100   }
 101
 102   // Tests a rectangle against the clipping region.  Returns one of:
 103   //   - splashClipAllInside if the entire rectangle is inside the
 104   //     clipping region, i.e., all pixels in the rectangle are
 105   //     visible
 106   //   - splashClipAllOutside if the entire rectangle is outside the
 107   //     clipping region, i.e., all the pixels in the rectangle are
 108   //     clipped
 109   //   - splashClipPartial if the rectangle is part inside and part
 110   //     outside the clipping region
 111   SplashClipResult testRect(int rectXMin, int rectYMin,
 112                             int rectXMax, int rectYMax);
 113
 114   // Similar to testRect, but tests a horizontal span.
 115   SplashClipResult testSpan(int spanXMin, int spanXMax, int spanY);
 116
 117   // Clips an anti-aliased line by setting pixels to zero.  On entry,
 118   // all non-zero pixels are between <x0> and <x1>.  This function
 119   // will update <x0> and <x1>.
 120   void clipAALine(SplashBitmap *aaBuf, int *x0, int *x1, int y,
 121     GBool adjustVertLine = gFalse);
 122
 123   // Get the rectangle part of the clip region.
 124   SplashCoord getXMin() { return xMin; }
 125   SplashCoord getXMax() { return xMax; }
 126   SplashCoord getYMin() { return yMin; }
 127   SplashCoord getYMax() { return yMax; }
 128
 129   // Get the rectangle part of the clip region, in integer coordinates.
 130   int getXMinI() { return xMinI; }
 131   int getXMaxI() { return xMaxI; }
 132   int getYMinI() { return yMinI; }
 133   int getYMaxI() { return yMaxI; }
 134
 135   // Get the number of arbitrary paths used by the clip region.
 136   int getNumPaths() { return length; }
 137
 138 protected:
 139
 140   SplashClip(SplashClip *clip);
 141   void grow(int nPaths);
 142
 143   GBool antialias;
 144   SplashCoord xMin, yMin, xMax, yMax;
 145   int xMinI, yMinI, xMaxI, yMaxI;
 146   SplashXPath **paths;
 147   Guchar *flags;
 148   SplashXPathScanner **scanners;
 149   int length, size;
 150 };
 151
 152 #endif