splash/SplashPath.h

//========================================================================
//
// SplashPath.h
//
//========================================================================

//========================================================================
//
// 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) 2018 Albert Astals Cid <aacid@kde.org>
// Copyright (C) 2018 Stefan Brüns <stefan.bruens@rwth-aachen.de>
//
// 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
//
//========================================================================

#ifndef SPLASHPATH_H
#define SPLASHPATH_H

#include "SplashTypes.h"

//------------------------------------------------------------------------
// SplashPathPoint
//------------------------------------------------------------------------

struct SplashPathPoint {
  SplashCoord x, y;
};

//------------------------------------------------------------------------
// SplashPath.flags
//------------------------------------------------------------------------

// first point on each subpath sets this flag
#define splashPathFirst         0x01

// last point on each subpath sets this flag
#define splashPathLast          0x02

// if the subpath is closed, its first and last points must be
// identical, and must set this flag
#define splashPathClosed        0x04

// curve control points set this flag
#define splashPathCurve         0x08

//------------------------------------------------------------------------
// SplashPathHint
//------------------------------------------------------------------------

struct SplashPathHint {
  int ctrl0, ctrl1;
  int firstPt, lastPt;
};

//------------------------------------------------------------------------
// SplashPath
//------------------------------------------------------------------------

class SplashPath {
public:

  // Create an empty path.
  SplashPath();

  // Copy a path.
  SplashPath *copy() { return new SplashPath(this); }

  ~SplashPath();

  SplashPath(const SplashPath&) = delete;
  SplashPath& operator=(const SplashPath&) = delete;
  SplashPath(SplashPath&& path);

  // Append <path> to <this>.
  void append(SplashPath *path);

  // Start a new subpath.
  SplashError moveTo(SplashCoord x, SplashCoord y);

  // Add a line segment to the last subpath.
  SplashError lineTo(SplashCoord x, SplashCoord y);

  // Add a third-order (cubic) Bezier curve segment to the last
  // subpath.
  SplashError curveTo(SplashCoord x1, SplashCoord y1,
		      SplashCoord x2, SplashCoord y2,
		      SplashCoord x3, SplashCoord y3);

  // Close the last subpath, adding a line segment if necessary.  If
  // <force> is true, this adds a line segment even if the current
  // point is equal to the first point in the subpath.
  SplashError close(bool force = false);

  // Add a stroke adjustment hint.  The controlling segments are
  // <ctrl0> and <ctrl1> (where segments are identified by their first
  // point), and the points to be adjusted are <firstPt> .. <lastPt>.
  void addStrokeAdjustHint(int ctrl0, int ctrl1, int firstPt, int lastPt);

  // Add (<dx>, <dy>) to every point on this path.
  void offset(SplashCoord dx, SplashCoord dy);

  // Get the points on the path.
  int getLength() { return length; }
  void getPoint(int i, double *x, double *y, unsigned char *f)
    { *x = pts[i].x; *y = pts[i].y; *f = flags[i]; }

  // Get the current point.
  bool getCurPt(SplashCoord *x, SplashCoord *y);

  // Reserve space for at least n points
  void reserve(int n);

protected:

  SplashPath(SplashPath *path);
  void grow(int nPts);
  bool noCurrentPoint() { return curSubpath == length; }
  bool onePointSubpath() { return curSubpath == length - 1; }
  bool openSubpath() { return curSubpath < length - 1; }

  SplashPathPoint *pts;		// array of points
  unsigned char *flags;		// array of flags
  int length, size;		// length/size of the pts and flags arrays
  int curSubpath;		// index of first point in last subpath

  SplashPathHint *hints;	// list of hints
  int hintsLength, hintsSize;

  friend class SplashXPath;
  friend class Splash;
};

#endif