ExtendedGeneralPath.java
/* ========================================================================
* PlantUML : a free UML diagram generator
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* (C) Copyright 2009-2024, Arnaud Roques
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* Original Author: Thierry Kormann
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package net.sourceforge.plantuml.klimt.drawing.g2d;
import java.awt.Rectangle;
import java.awt.Shape;
import java.awt.geom.AffineTransform;
import java.awt.geom.Arc2D;
import java.awt.geom.GeneralPath;
import java.awt.geom.PathIterator;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.util.Arrays;
import net.sourceforge.plantuml.klimt.geom.XPoint2D;
import net.sourceforge.plantuml.log.Logme;
/**
* The <code>ExtendedGeneralPath</code> class represents a geometric path
* constructed from straight lines, quadratic and cubic (Bezier) curves and
* elliptical arc. This class delegates lines and curves to an enclosed
* <code>GeneralPath</code>. Elliptical arc is implemented using an
* <code>Arc2D</code> in double precision.
*
* <p>
* <b>Warning</b> : An elliptical arc may be composed of several path segments.
* For further details, see the SVG Appendix F.6
*
* @author <a href="mailto:Thierry.Kormann@sophia.inria.fr">Thierry Kormann</a>
* @version $Id: ExtendedGeneralPath.java 594018 2007-11-12 04:17:41Z cam $
*/
public class ExtendedGeneralPath implements Shape, Cloneable {
/** The enclosed general path. */
private GeneralPath path;
private int numVals = 0;
private int numSeg = 0;
private double[] values = null;
private int[] types = null;
private double mx;
private double my;
private double cx;
private double cy;
/**
* Constructs a new <code>ExtendedGeneralPath</code>.
*/
public ExtendedGeneralPath() {
path = new GeneralPath();
}
/**
* Constructs a new <code>ExtendedGeneralPath</code> with the specified winding
* rule to control operations that require the interior of the path to be
* defined.
*/
public ExtendedGeneralPath(int rule) {
path = new GeneralPath(rule);
}
/**
* Constructs a new <code>ExtendedGeneralPath</code> object with the specified
* winding rule and the specified initial capacity to store path coordinates.
*/
public ExtendedGeneralPath(int rule, int initialCapacity) {
path = new GeneralPath(rule, initialCapacity);
}
/**
* Constructs a new <code>ExtendedGeneralPath</code> object from an arbitrary
* <code>Shape</code> object.
*/
public ExtendedGeneralPath(Shape s) {
this();
append(s, false);
}
/**
* Adds an elliptical arc, defined by two radii, an angle from the x-axis, a
* flag to choose the large arc or not, a flag to indicate if we increase or
* decrease the angles and the final point of the arc.
*
* @param rx the x radius of the ellipse
* @param ry the y radius of the ellipse
*
* @param angle the angle from the x-axis of the current coordinate
* system to the x-axis of the ellipse in degrees.
*
* @param largeArcFlag the large arc flag. If true the arc spanning less than or
* equal to 180 degrees is chosen, otherwise the arc
* spanning greater than 180 degrees is chosen
*
* @param sweepFlag the sweep flag. If true the line joining center to arc
* sweeps through decreasing angles otherwise it sweeps
* through increasing angles
*
* @param x the absolute x coordinate of the final point of the arc.
* @param y the absolute y coordinate of the final point of the arc.
*/
public void arcTo(double rx, double ry, double angle, boolean largeArcFlag, boolean sweepFlag, double x, double y) {
// Ensure radii are valid
if (rx == 0 || ry == 0) {
lineTo(x, y);
return;
}
checkMoveTo(); // check if prev command was moveto
// Get the current (x, y) coordinates of the path
final double x0 = cx;
final double y0 = cy;
if (x0 == x && y0 == y) {
// If the endpoints (x, y) and (x0, y0) are identical, then this
// is equivalent to omitting the elliptical arc segment entirely.
return;
}
final Arc2D arc = computeArc(x0, y0, rx, ry, angle, largeArcFlag, sweepFlag, x, y);
if (arc == null) {
return;
}
final AffineTransform t = AffineTransform.getRotateInstance(Math.toRadians(angle), arc.getCenterX(),
arc.getCenterY());
final Shape s = t.createTransformedShape(arc);
path.append(s, true);
makeRoom(7);
types[numSeg++] = ExtendedPathIterator.SEG_ARCTO;
values[numVals++] = rx;
values[numVals++] = ry;
values[numVals++] = angle;
values[numVals++] = largeArcFlag ? 1 : 0;
values[numVals++] = sweepFlag ? 1 : 0;
cx = values[numVals++] = x;
cy = values[numVals++] = y;
}
/**
* This constructs an unrotated Arc2D from the SVG specification of an
* Elliptical arc. To get the final arc you need to apply a rotation transform
* such as:
*
* AffineTransform.getRotateInstance (angle, arc.getX()+arc.getWidth()/2,
* arc.getY()+arc.getHeight()/2);
*/
public static Arc2D computeArc(double x0, double y0, double rx, double ry, double angle, boolean largeArcFlag,
boolean sweepFlag, double x, double y) {
//
// Elliptical arc implementation based on the SVG specification notes
//
// Compute the half distance between the current and the final point
final double dx2 = (x0 - x) / 2.0;
final double dy2 = (y0 - y) / 2.0;
// Convert angle from degrees to radians
angle = Math.toRadians(angle % 360.0);
final double cosAngle = Math.cos(angle);
final double sinAngle = Math.sin(angle);
//
// Step 1 : Compute (x1, y1)
//
final double x1 = cosAngle * dx2 + sinAngle * dy2;
final double y1 = -sinAngle * dx2 + cosAngle * dy2;
// Ensure radii are large enough
rx = Math.abs(rx);
ry = Math.abs(ry);
double prx = rx * rx;
double pry = ry * ry;
final double px1 = x1 * x1;
final double py1 = y1 * y1;
// check that radii are large enough
final double radiiCheck = px1 / prx + py1 / pry;
if (radiiCheck > 1) {
rx = Math.sqrt(radiiCheck) * rx;
ry = Math.sqrt(radiiCheck) * ry;
prx = rx * rx;
pry = ry * ry;
}
//
// Step 2 : Compute (cx1, cy1)
//
double sign = (largeArcFlag == sweepFlag) ? -1 : 1;
double sq = ((prx * pry) - (prx * py1) - (pry * px1)) / ((prx * py1) + (pry * px1));
sq = (sq < 0) ? 0 : sq;
final double coef = sign * Math.sqrt(sq);
final double cx1 = coef * ((rx * y1) / ry);
final double cy1 = coef * -((ry * x1) / rx);
//
// Step 3 : Compute (cx, cy) from (cx1, cy1)
//
final double sx2 = (x0 + x) / 2.0;
final double sy2 = (y0 + y) / 2.0;
final double cx = sx2 + (cosAngle * cx1 - sinAngle * cy1);
final double cy = sy2 + (sinAngle * cx1 + cosAngle * cy1);
//
// Step 4 : Compute the angleStart (angle1) and the angleExtent (dangle)
//
final double ux = (x1 - cx1) / rx;
final double uy = (y1 - cy1) / ry;
final double vx = (-x1 - cx1) / rx;
final double vy = (-y1 - cy1) / ry;
// Compute the angle start
double n = Math.sqrt((ux * ux) + (uy * uy));
double p = ux; // (1 * ux) + (0 * uy)
sign = (uy < 0) ? -1.0 : 1.0;
double angleStart = Math.toDegrees(sign * Math.acos(p / n));
// Compute the angle extent
n = Math.sqrt((ux * ux + uy * uy) * (vx * vx + vy * vy));
p = ux * vx + uy * vy;
sign = (ux * vy - uy * vx < 0) ? -1.0 : 1.0;
double angleExtent = Math.toDegrees(sign * Math.acos(p / n));
if (!sweepFlag && angleExtent > 0) {
angleExtent -= 360f;
} else if (sweepFlag && angleExtent < 0) {
angleExtent += 360f;
}
angleExtent %= 360f;
angleStart %= 360f;
//
// We can now build the resulting Arc2D in double precision
//
final Arc2D.Double arc = new Arc2D.Double();
arc.x = cx - rx;
arc.y = cy - ry;
arc.width = rx * 2.0;
arc.height = ry * 2.0;
arc.start = -angleStart;
arc.extent = -angleExtent;
return arc;
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public void moveTo(double x, double y) {
// Don't add moveto to general path unless there is a reason.
makeRoom(2);
types[numSeg++] = PathIterator.SEG_MOVETO;
cx = mx = values[numVals++] = x;
cy = my = values[numVals++] = y;
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public void lineTo(double x, double y) {
checkMoveTo(); // check if prev command was moveto
path.lineTo(x, y);
makeRoom(2);
types[numSeg++] = PathIterator.SEG_LINETO;
cx = values[numVals++] = x;
cy = values[numVals++] = y;
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public void quadTo(double x1, double y1, double x2, double y2) {
checkMoveTo(); // check if prev command was moveto
path.quadTo(x1, y1, x2, y2);
makeRoom(4);
types[numSeg++] = PathIterator.SEG_QUADTO;
values[numVals++] = x1;
values[numVals++] = y1;
cx = values[numVals++] = x2;
cy = values[numVals++] = y2;
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public void curveTo(double x1, double y1, double x2, double y2, double x3, double y3) {
checkMoveTo(); // check if prev command was moveto
path.curveTo(x1, y1, x2, y2, x3, y3);
makeRoom(6);
types[numSeg++] = PathIterator.SEG_CUBICTO;
values[numVals++] = x1;
values[numVals++] = y1;
values[numVals++] = x2;
values[numVals++] = y2;
cx = values[numVals++] = x3;
cy = values[numVals++] = y3;
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public void closePath() {
// Don't double close path.
if (numSeg != 0 && types[numSeg - 1] == PathIterator.SEG_CLOSE) {
return;
}
// Only close path if the previous command wasn't a moveto
if (numSeg != 0 && types[numSeg - 1] != PathIterator.SEG_MOVETO) {
path.closePath();
}
makeRoom(0);
types[numSeg++] = PathIterator.SEG_CLOSE;
cx = mx;
cy = my;
}
/**
* Checks if previous command was a moveto command, skipping a close command (if
* present).
*/
protected void checkMoveTo() {
if (numSeg == 0) {
return;
}
switch (types[numSeg - 1]) {
case PathIterator.SEG_MOVETO:
path.moveTo(values[numVals - 2], values[numVals - 1]);
break;
case PathIterator.SEG_CLOSE:
if (numSeg == 1) {
return;
}
if (types[numSeg - 2] == PathIterator.SEG_MOVETO) {
path.moveTo(values[numVals - 2], values[numVals - 1]);
}
break;
default:
break;
}
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public void append(Shape s, boolean connect) {
append(s.getPathIterator(new AffineTransform()), connect);
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public void append(PathIterator pi, boolean connect) {
final double[] vals = new double[6];
while (!pi.isDone()) {
Arrays.fill(vals, 0);
int type = pi.currentSegment(vals);
pi.next();
if (connect && numVals != 0) {
if (type == PathIterator.SEG_MOVETO) {
final double x = vals[0];
final double y = vals[1];
if (x != cx || y != cy) {
// Change MOVETO to LINETO.
type = PathIterator.SEG_LINETO;
} else {
// Redundant segment (move to current loc) drop it...
if (pi.isDone()) {
break; // Nothing interesting
}
type = pi.currentSegment(vals);
pi.next();
}
}
connect = false;
}
switch (type) {
case PathIterator.SEG_CLOSE:
closePath();
break;
case PathIterator.SEG_MOVETO:
moveTo(vals[0], vals[1]);
break;
case PathIterator.SEG_LINETO:
lineTo(vals[0], vals[1]);
break;
case PathIterator.SEG_QUADTO:
quadTo(vals[0], vals[1], vals[2], vals[3]);
break;
case PathIterator.SEG_CUBICTO:
curveTo(vals[0], vals[1], vals[2], vals[3], vals[4], vals[5]);
break;
}
}
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public void append(ExtendedPathIterator epi, boolean connect) {
final double[] vals = new double[7];
while (!epi.isDone()) {
Arrays.fill(vals, 0);
int type = epi.currentSegment(vals);
epi.next();
if (connect && numVals != 0) {
if (type == PathIterator.SEG_MOVETO) {
final double x = vals[0];
final double y = vals[1];
if ((x != cx) || (y != cy)) {
// Change MOVETO to LINETO.
type = PathIterator.SEG_LINETO;
} else {
// Redundant segment (move to current loc) drop it...
if (epi.isDone()) {
break; // Nothing interesting
}
type = epi.currentSegment(vals);
epi.next();
}
}
connect = false;
}
switch (type) {
case PathIterator.SEG_CLOSE:
closePath();
break;
case PathIterator.SEG_MOVETO:
moveTo(vals[0], vals[1]);
break;
case PathIterator.SEG_LINETO:
lineTo(vals[0], vals[1]);
break;
case PathIterator.SEG_QUADTO:
quadTo(vals[0], vals[1], vals[2], vals[3]);
break;
case PathIterator.SEG_CUBICTO:
curveTo(vals[0], vals[1], vals[2], vals[3], vals[4], vals[5]);
break;
case ExtendedPathIterator.SEG_ARCTO:
arcTo(vals[0], vals[1], vals[2], vals[3] != 0, vals[4] != 0, vals[5], vals[6]);
break;
}
}
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public int getWindingRule() {
return path.getWindingRule();
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public void setWindingRule(int rule) {
path.setWindingRule(rule);
}
/**
* get the current position or <code>null</code>.
*/
public XPoint2D getCurrentPoint() {
if (numVals == 0) {
return null;
}
return new XPoint2D(cx, cy);
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public void reset() {
path.reset();
numSeg = 0;
numVals = 0;
values = null;
types = null;
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public void transform(AffineTransform at) {
if (at.getType() != AffineTransform.TYPE_IDENTITY) {
throw new IllegalArgumentException("ExtendedGeneralPaths can not be transformed");
}
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public Shape createTransformedShape(AffineTransform at) {
return path.createTransformedShape(at);
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public Rectangle getBounds() {
return path.getBounds();
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public Rectangle2D getBounds2D() {
return path.getBounds2D();
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public boolean contains(double x, double y) {
return path.contains(x, y);
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public boolean contains(Point2D p) {
return path.contains(p);
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public boolean contains(double x, double y, double w, double h) {
return path.contains(x, y, w, h);
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public boolean contains(Rectangle2D r) {
return path.contains(r);
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public boolean intersects(double x, double y, double w, double h) {
return path.intersects(x, y, w, h);
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public boolean intersects(Rectangle2D r) {
return path.intersects(r);
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public PathIterator getPathIterator(AffineTransform at) {
return path.getPathIterator(at);
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public PathIterator getPathIterator(AffineTransform at, double flatness) {
return path.getPathIterator(at, flatness);
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public ExtendedPathIterator getExtendedPathIterator() {
return new EPI();
}
class EPI implements ExtendedPathIterator {
private int segNum = 0;
private int valsIdx = 0;
public int currentSegment() {
return types[segNum];
}
public int currentSegment(double[] coords) {
final int ret = types[segNum];
switch (ret) {
case SEG_CLOSE:
break;
case SEG_MOVETO:
case SEG_LINETO:
coords[0] = values[valsIdx];
coords[1] = values[valsIdx + 1];
break;
case SEG_QUADTO:
coords[0] = values[valsIdx];
coords[1] = values[valsIdx + 1];
coords[2] = values[valsIdx + 2];
coords[3] = values[valsIdx + 3];
break;
case SEG_CUBICTO:
coords[0] = values[valsIdx];
coords[1] = values[valsIdx + 1];
coords[2] = values[valsIdx + 2];
coords[3] = values[valsIdx + 3];
coords[4] = values[valsIdx + 4];
coords[5] = values[valsIdx + 5];
break;
case SEG_ARCTO:
coords[0] = values[valsIdx];
coords[1] = values[valsIdx + 1];
coords[2] = values[valsIdx + 2];
coords[3] = values[valsIdx + 3];
coords[4] = values[valsIdx + 4];
coords[5] = values[valsIdx + 5];
coords[6] = values[valsIdx + 6];
break;
}
return ret;
}
public int getWindingRule() {
return path.getWindingRule();
}
public boolean isDone() {
return segNum == numSeg;
}
public void next() {
final int type = types[segNum++];
switch (type) {
case SEG_CLOSE:
break;
case SEG_MOVETO: // fallthrough is intended
case SEG_LINETO:
valsIdx += 2;
break;
case SEG_QUADTO:
valsIdx += 4;
break;
case SEG_CUBICTO:
valsIdx += 6;
break;
case SEG_ARCTO:
valsIdx += 7;
break;
}
}
}
/**
* Delegates to the enclosed <code>GeneralPath</code>.
*/
public Object clone() {
try {
final ExtendedGeneralPath result = (ExtendedGeneralPath) super.clone();
result.path = (GeneralPath) path.clone();
if (values != null) {
result.values = new double[values.length];
System.arraycopy(values, 0, result.values, 0, values.length);
}
result.numVals = numVals;
if (types != null) {
result.types = new int[types.length];
System.arraycopy(types, 0, result.types, 0, types.length);
}
result.numSeg = numSeg;
return result;
} catch (CloneNotSupportedException ex) {
Logme.error(ex);
}
return null;
}
/**
* Make sure, that the requested number of slots in vales[] are available. Must
* be called even for numValues = 0, because it is also used for initialization
* of those arrays.
*
* @param numValues number of requested coordinates
*/
private void makeRoom(int numValues) {
if (values == null) {
values = new double[2 * numValues];
types = new int[2];
numVals = 0;
numSeg = 0;
return;
}
final int newSize = numVals + numValues;
if (newSize > values.length) {
int nlen = values.length * 2;
if (nlen < newSize) {
nlen = newSize;
}
final double[] nvals = new double[nlen];
System.arraycopy(values, 0, nvals, 0, numVals);
values = nvals;
}
if (numSeg == types.length) {
final int[] ntypes = new int[types.length * 2];
System.arraycopy(types, 0, ntypes, 0, types.length);
types = ntypes;
}
}
}