splash/SplashPath.h

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

#ifndef SPLASHPATH_H
#define SPLASHPATH_H

#ifdef USE_GCC_PRAGMAS
#pragma interface
#endif

#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

// clockwise arc center points set this flag
#define splashPathArcCW  0x10

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

class SplashPath {
public:

  // Create an empty path.
  SplashPath();

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

  ~SplashPath();

  // 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);

  // Add a clockwise circular arc with center (xc, yc) and endpoint
  // (x1, y1).
  SplashError arcCWTo(SplashCoord x1, SplashCoord y1,
		      SplashCoord xc, SplashCoord yc);

  // Close the last subpath, adding a line segment if necessary.
  SplashError close();

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

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

private:

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

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

  friend class SplashXPath;
  friend class Splash;
};

#endif