File	Doc	Category	Size	Date	Package
ArcIterator.java	API Doc	Java SE 5 API	8890	Fri Aug 26 14:56:52 BST 2005	java.awt.geom

ArcIterator

• java.lang.Object

Fields Summary
double	x
double	y
double	w
double	h
double	angStRad
double	increment
double	cv
AffineTransform	affine
int	index
int	arcSegs
int	lineSegs

Constructors Summary

ArcIterator(Arc2D a, AffineTransform at) this.w = a.getWidth() / 2; this.h = a.getHeight() / 2; this.x = a.getX() + w; this.y = a.getY() + h; this.angStRad = -Math.toRadians(a.getAngleStart()); this.affine = at; double ext = -a.getAngleExtent(); if (ext >= 360.0 || ext <= -360) { arcSegs = 4; this.increment = Math.PI / 2; // btan(Math.PI / 2); this.cv = 0.5522847498307933; if (ext < 0) { increment = -increment; cv = -cv; } } else { arcSegs = (int) Math.ceil(Math.abs(ext) / 90.0); this.increment = Math.toRadians(ext / arcSegs); this.cv = btan(increment); if (cv == 0) { arcSegs = 0; } } switch (a.getArcType()) { case Arc2D.OPEN: lineSegs = 0; break; case Arc2D.CHORD: lineSegs = 1; break; case Arc2D.PIE: lineSegs = 2; break; } if (w < 0 || h < 0) { arcSegs = lineSegs = -1; }

Methods Summary
private static double	btan(double increment) increment /= 2.0; return 4.0 / 3.0 * Math.sin(increment) / (1.0 + Math.cos(increment));
public int	currentSegment(float[] coords) Returns the coordinates and type of the current path segment in the iteration. The return value is the path segment type: SEG_MOVETO, SEG_LINETO, SEG_QUADTO, SEG_CUBICTO, or SEG_CLOSE. A float array of length 6 must be passed in and may be used to store the coordinates of the point(s). Each point is stored as a pair of float x,y coordinates. SEG_MOVETO and SEG_LINETO types will return one point, SEG_QUADTO will return two points, SEG_CUBICTO will return 3 points and SEG_CLOSE will not return any points. see #SEG_MOVETO see #SEG_LINETO see #SEG_QUADTO see #SEG_CUBICTO see #SEG_CLOSE if (isDone()) { throw new NoSuchElementException("arc iterator out of bounds"); } double angle = angStRad; if (index == 0) { coords[0] = (float) (x + Math.cos(angle) * w); coords[1] = (float) (y + Math.sin(angle) * h); if (affine != null) { affine.transform(coords, 0, coords, 0, 1); } return SEG_MOVETO; } if (index > arcSegs) { if (index == arcSegs + lineSegs) { return SEG_CLOSE; } coords[0] = (float) x; coords[1] = (float) y; if (affine != null) { affine.transform(coords, 0, coords, 0, 1); } return SEG_LINETO; } angle += increment * (index - 1); double relx = Math.cos(angle); double rely = Math.sin(angle); coords[0] = (float) (x + (relx - cv * rely) * w); coords[1] = (float) (y + (rely + cv * relx) * h); angle += increment; relx = Math.cos(angle); rely = Math.sin(angle); coords[2] = (float) (x + (relx + cv * rely) * w); coords[3] = (float) (y + (rely - cv * relx) * h); coords[4] = (float) (x + relx * w); coords[5] = (float) (y + rely * h); if (affine != null) { affine.transform(coords, 0, coords, 0, 3); } return SEG_CUBICTO;
public int	currentSegment(double[] coords) Returns the coordinates and type of the current path segment in the iteration. The return value is the path segment type: SEG_MOVETO, SEG_LINETO, SEG_QUADTO, SEG_CUBICTO, or SEG_CLOSE. A double array of length 6 must be passed in and may be used to store the coordinates of the point(s). Each point is stored as a pair of double x,y coordinates. SEG_MOVETO and SEG_LINETO types will return one point, SEG_QUADTO will return two points, SEG_CUBICTO will return 3 points and SEG_CLOSE will not return any points. see #SEG_MOVETO see #SEG_LINETO see #SEG_QUADTO see #SEG_CUBICTO see #SEG_CLOSE if (isDone()) { throw new NoSuchElementException("arc iterator out of bounds"); } double angle = angStRad; if (index == 0) { coords[0] = x + Math.cos(angle) * w; coords[1] = y + Math.sin(angle) * h; if (affine != null) { affine.transform(coords, 0, coords, 0, 1); } return SEG_MOVETO; } if (index > arcSegs) { if (index == arcSegs + lineSegs) { return SEG_CLOSE; } coords[0] = x; coords[1] = y; if (affine != null) { affine.transform(coords, 0, coords, 0, 1); } return SEG_LINETO; } angle += increment * (index - 1); double relx = Math.cos(angle); double rely = Math.sin(angle); coords[0] = x + (relx - cv * rely) * w; coords[1] = y + (rely + cv * relx) * h; angle += increment; relx = Math.cos(angle); rely = Math.sin(angle); coords[2] = x + (relx + cv * rely) * w; coords[3] = y + (rely - cv * relx) * h; coords[4] = x + relx * w; coords[5] = y + rely * h; if (affine != null) { affine.transform(coords, 0, coords, 0, 3); } return SEG_CUBICTO;
public int	getWindingRule() Return the winding rule for determining the insideness of the path. see #WIND_EVEN_ODD see #WIND_NON_ZERO return WIND_NON_ZERO;
public boolean	isDone() Tests if there are more points to read. return true if there are more points to read return index > arcSegs + lineSegs;
public void	next() Moves the iterator to the next segment of the path forwards along the primary direction of traversal as long as there are more points in that direction. index++;