/*
* Copyright (c) 1997, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
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*/
package java.awt.geom;
import java.util.*;
/**
* A utility class to iterate over the path segments of an rounded rectangle
* through the PathIterator interface.
*
* @author Jim Graham
*/
class RoundRectIterator implements PathIterator {
double x, y, w, h, aw, ah;
AffineTransform affine;
int index;
RoundRectIterator(RoundRectangle2D rr, AffineTransform at) {
this.x = rr.getX();
this.y = rr.getY();
this.w = rr.getWidth();
this.h = rr.getHeight();
this.aw = Math.min(w, Math.abs(rr.getArcWidth()));
this.ah = Math.min(h, Math.abs(rr.getArcHeight()));
this.affine = at;
if (aw < 0 || ah < 0) {
// Don't draw anything...
index = ctrlpts.length;
}
}
/**
* Return the winding rule for determining the insideness of the
* path.
* @see #WIND_EVEN_ODD
* @see #WIND_NON_ZERO
*/
public int getWindingRule() {
return WIND_NON_ZERO;
}
/**
* Tests if there are more points to read.
* @return true if there are more points to read
*/
public boolean isDone() {
return index >= ctrlpts.length;
}
/**
* 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.
*/
public void next() {
index++;
}
private static final double angle = Math.PI / 4.0;
private static final double a = 1.0 - Math.cos(angle);
private static final double b = Math.tan(angle);
private static final double c = Math.sqrt(1.0 + b * b) - 1 + a;
private static final double cv = 4.0 / 3.0 * a * b / c;
private static final double acv = (1.0 - cv) / 2.0;
// For each array:
// 4 values for each point {v0, v1, v2, v3}:
// point = (x + v0 * w + v1 * arcWidth,
// y + v2 * h + v3 * arcHeight);
private static double ctrlpts[][] = {
{ 0.0, 0.0, 0.0, 0.5 },
{ 0.0, 0.0, 1.0, -0.5 },
{ 0.0, 0.0, 1.0, -acv,
0.0, acv, 1.0, 0.0,
0.0, 0.5, 1.0, 0.0 },
{ 1.0, -0.5, 1.0, 0.0 },
{ 1.0, -acv, 1.0, 0.0,
1.0, 0.0, 1.0, -acv,
1.0, 0.0, 1.0, -0.5 },
{ 1.0, 0.0, 0.0, 0.5 },
{ 1.0, 0.0, 0.0, acv,
1.0, -acv, 0.0, 0.0,
1.0, -0.5, 0.0, 0.0 },
{ 0.0, 0.5, 0.0, 0.0 },
{ 0.0, acv, 0.0, 0.0,
0.0, 0.0, 0.0, acv,
0.0, 0.0, 0.0, 0.5 },
{},
};
private static int types[] = {
SEG_MOVETO,
SEG_LINETO, SEG_CUBICTO,
SEG_LINETO, SEG_CUBICTO,
SEG_LINETO, SEG_CUBICTO,
SEG_LINETO, SEG_CUBICTO,
SEG_CLOSE,
};
/**
* 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
*/
public int currentSegment(float[] coords) {
if (isDone()) {
throw new NoSuchElementException("roundrect iterator out of bounds");
}
double ctrls[] = ctrlpts[index];
int nc = 0;
for (int i = 0; i < ctrls.length; i += 4) {
coords[nc++] = (float) (x + ctrls[i + 0] * w + ctrls[i + 1] * aw);
coords[nc++] = (float) (y + ctrls[i + 2] * h + ctrls[i + 3] * ah);
}
if (affine != null) {
affine.transform(coords, 0, coords, 0, nc / 2);
}
return types[index];
}
/**
* 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
*/
public int currentSegment(double[] coords) {
if (isDone()) {
throw new NoSuchElementException("roundrect iterator out of bounds");
}
double ctrls[] = ctrlpts[index];
int nc = 0;
for (int i = 0; i < ctrls.length; i += 4) {
coords[nc++] = (x + ctrls[i + 0] * w + ctrls[i + 1] * aw);
coords[nc++] = (y + ctrls[i + 2] * h + ctrls[i + 3] * ah);
}
if (affine != null) {
affine.transform(coords, 0, coords, 0, nc / 2);
}
return types[index];
}
}