2006-04-24 Sven de Marothy <sven@physto.se>

	* gnu/java/awt/java2d/Segment.java: New file.
	* gnu/java/awt/java2d/CubicSegment.java: New file.
	* gnu/java/awt/java2d/QuadSegment.java: New file.
	* gnu/java/awt/java2d/LineSegment.java: New file.
	* java/awt/BasicStroke.java
	(start): New field.
	(end): New field.
	(createStrokedShape): Implemented.
	(solidStroke): New method.
	(dashedStroke): New method.
	(capEnds): New method.
	(convertPath): New method.
	(addSegments): New method.
	(capEnd): New method.
	(lineIntersection): New method.
	(joinSegments): New method.

4 files changed, 575 insertions, 0 deletions

diff --git a/gnu/java/awt/java2d/CubicSegment.java b/gnu/java/awt/java2d/CubicSegment.java
new file mode 100644
index 000000000..1e568f722
--- /dev/null
+++ b/gnu/java/awt/java2d/CubicSegment.java
@@ -0,0 +1,128 @@
+/* CubicSegment.java -- Cubic segment used for BasicStroke
+   Copyright (C) 2006 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath 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 for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package gnu.java.awt.java2d;
+
+
+import java.awt.geom.Point2D;
+
+/**
+ * Cubic Bezier curve segment
+ */
+public class CubicSegment extends Segment
+{
+  public Point2D cp1; // control points
+  public Point2D cp2; // control points
+
+  /**
+   * Constructor - takes coordinates of the starting point,
+   * first control point, second control point and end point,
+   * respecively.
+   */
+  public CubicSegment(double x1, double y1, double c1x, double c1y,
+                      double c2x, double c2y, double x2, double y2)
+  {
+    super();
+    P1 = new Point2D.Double(x1, y1);
+    P2 = new Point2D.Double(x2, y2);
+    cp1 = new Point2D.Double(c1x, c1y);
+    cp2 = new Point2D.Double(c2x, c2y);
+  }
+
+  public CubicSegment(Point2D p1, Point2D cp1, Point2D cp2, Point2D p2)
+  {
+    super();
+    P1 = p1;
+    P2 = p2;
+    this.cp1 = cp1;
+    this.cp2 = cp2;
+  }
+
+  /**
+   * Clones this segment
+   */
+  public Object clone()
+  {
+    return new CubicSegment(P1.getX(), P1.getY(), cp1.getX(), cp1.getY(),
+                            cp2.getX(), cp2.getY(), P2.getX(), P2.getY());
+  }
+
+  /**
+   * Get the "top" and "bottom" segments of this segment.
+   * First array element is p0 + normal, second is p0 - normal.
+   */
+  public Segment[] getDisplacedSegments(double radius)
+  {
+    this.radius = radius;
+    double x0 = P1.getX();
+    double y0 = P1.getY();
+    double x1 = cp1.getX();
+    double y1 = cp1.getY();
+    double x2 = cp2.getX();
+    double y2 = cp2.getY();
+    double x3 = P2.getX();
+    double y3 = P2.getY();
+    double[] p1 = normal(x0, y0, x1, y1);
+    double[] p2 = normal(x2, y2, x3, y3);
+
+    
+    // FIXME: Doesn't compile.
+    // return new Segment[]{s1, s2};
+    return new Segment[0];
+  }
+
+  public void reverse()
+  {
+    Point2D temp = P1;
+    P1 = P2;
+    P2 = temp;
+    temp = cp1;
+    cp1 = cp2;
+    cp2 = temp;
+  }
+
+  public double[] first()
+  {
+    return new double[]{cp1.getX(), cp1.getY()}; 
+  }
+
+  public double[] last()
+  {
+    return new double[]{cp2.getX(), cp2.getY()}; 
+  }
+} // class CubicSegment
diff --git a/gnu/java/awt/java2d/LineSegment.java b/gnu/java/awt/java2d/LineSegment.java
new file mode 100644
index 000000000..9c0bcc7ea
--- /dev/null
+++ b/gnu/java/awt/java2d/LineSegment.java
@@ -0,0 +1,103 @@
+/* LineSegment.java -- Line segment used for BasicStroke
+   Copyright (C) 2006 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath 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 for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package gnu.java.awt.java2d;
+
+
+import java.awt.geom.Point2D;
+
+public class LineSegment extends Segment
+{
+  public LineSegment(double x1, double y1, double x2, double y2)
+  {
+    super();
+    P1 = new Point2D.Double(x1, y1);
+    P2 = new Point2D.Double(x2, y2);
+  }
+
+  public LineSegment(Point2D p1, Point2D p2)
+  {
+    super();
+    P1 = (Point2D) p1.clone();
+    P2 = (Point2D) p2.clone();
+  }
+
+  /**
+   * Clones this segment
+   */
+  public Object clone()
+  {
+    return new LineSegment(P1, P2);
+  }
+
+  /**
+   * Get the "top" and "bottom" segments of this segment.
+   * First array element is p0 + normal, second is p0 - normal.
+   */
+  public Segment[] getDisplacedSegments(double radius)
+  {
+    this.radius = radius;
+    double x0 = P1.getX();
+    double y0 = P1.getY();
+    double x1 = P2.getX();
+    double y1 = P2.getY();
+    double[] p = normal(x0, y0, x1, y1);
+    Segment s1 = (new LineSegment(x0 + p[0], y0 + p[1],
+                                  x1 + p[0], y1 + p[1] ));
+    Segment s2 = (new LineSegment(x0 - p[0], y0 - p[1],
+                                  x1 - p[0], y1 - p[1] ));
+    return new Segment[]{s1, s2};
+  }
+
+  public void reverse()
+  {
+    Point2D p = P1;
+    P1 = P2;
+    P2 = p;
+  }
+
+  public double[] first()
+  {
+    return new double[]{P2.getX(), P2.getY()}; 
+  }
+
+  public double[] last()
+  {
+    return new double[]{P1.getX(), P1.getY()}; 
+  }
+} // class LineSegment
diff --git a/gnu/java/awt/java2d/QuadSegment.java b/gnu/java/awt/java2d/QuadSegment.java
new file mode 100644
index 000000000..9c15a8cfd
--- /dev/null
+++ b/gnu/java/awt/java2d/QuadSegment.java
@@ -0,0 +1,213 @@
+/* QuadSegment.java -- QuadCurve segment used for BasicStroke
+   Copyright (C) 2006 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath 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 for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package gnu.java.awt.java2d;
+
+
+import java.awt.geom.Point2D;
+import java.awt.geom.QuadCurve2D;
+
+/**
+ * Quadratic Bezier curve segment
+ *
+ * Note: Most peers don't support quadratics directly, so it might make
+ * sense to represent them as cubics internally and just be done with it.
+ * I think we should be peer-agnostic, however, and stay faithful to the
+ * input geometry types as far as possible.
+ */
+public class QuadSegment extends Segment
+{
+  public Point2D cp; // control point
+
+  /**
+   * Constructor, takes the coordinates of the start, control,
+   * and end point, respectively.
+   */
+  public QuadSegment(double x1, double y1, double cx, double cy, double x2,
+                     double y2)
+  {
+    super();
+    P1 = new Point2D.Double(x1, y1);
+    P2 = new Point2D.Double(x2, y2);
+    cp = new Point2D.Double(cx, cy);
+  }
+
+  public QuadSegment(Point2D p1, Point2D cp, Point2D p2)
+  {
+    super();
+    P1 = p1;
+    P2 = p2;
+    this.cp = cp;
+  }
+
+  public QuadSegment(QuadCurve2D curve)
+  {
+    super();
+    P1 = curve.getP1();
+    P2 = curve.getP2();
+    this.cp = curve.getCtrlPt();
+  }
+
+  /**
+   * Clones this segment
+   */
+  public Object clone()
+  {
+    return new QuadSegment(P1.getX(), P1.getY(), cp.getX(), cp.getY(),
+                           P2.getX(), P2.getY());
+  }
+
+  /**
+   * Get the "top" and "bottom" segments of a given segment.
+   * First array element is p0 + normal, second is p0 - normal.
+   */
+  public Segment[] getDisplacedSegments(double radius)
+  {
+    this.radius = radius;
+    double x0 = P1.getX();
+    double y0 = P1.getY();
+    double x1 = cp.getX();
+    double y1 = cp.getY();
+    double x2 = P2.getX();
+    double y2 = P2.getY();
+
+    QuadCurve2D left = new QuadCurve2D.Double();
+    QuadCurve2D right = new QuadCurve2D.Double();
+    QuadCurve2D orig = new QuadCurve2D.Double(x0, y0, x1, y1, x2, y2);
+    orig.subdivide(left, right);
+
+    QuadSegment s1 = offsetSubdivided(left, true);
+    QuadSegment s2 = offsetSubdivided(left, false);
+
+    s1.add( offsetSubdivided(right, true) );
+    s2.add( offsetSubdivided(right, false) );
+
+    return new Segment[]{s1, s2};
+  }
+  
+  private QuadSegment offsetSubdivided(QuadCurve2D curve, boolean plus)
+  {
+    double[] n1 = normal(curve.getX1(), curve.getY1(), 
+                         curve.getCtrlX(), curve.getCtrlY());
+    double[] n2 = normal(curve.getCtrlX(), curve.getCtrlY(),
+                         curve.getX2(), curve.getY2());
+
+    Point2D cp;
+    QuadSegment s;
+    if( plus )
+      {
+        cp = lineIntersection(curve.getX1() + n1[0], 
+                              curve.getY1() + n1[1],
+                              curve.getCtrlX() + n1[0],
+                              curve.getCtrlY() + n1[1],
+                              curve.getCtrlX() + n2[0],
+                              curve.getCtrlY() + n2[1],
+                              curve.getX2() + n2[0], 
+                              curve.getY2() + n2[1], true);
+        s = new QuadSegment(curve.getX1() + n1[0], curve.getY1() + n1[1],
+                            cp.getX(), cp.getY(),
+                            curve.getX2() + n2[0], curve.getY2() + n2[1]);
+      }
+    else
+      {
+        cp = lineIntersection(curve.getX1() - n1[0], 
+                              curve.getY1() - n1[1],
+                              curve.getCtrlX() - n1[0],
+                              curve.getCtrlY() - n1[1],
+                              curve.getCtrlX() - n2[0],
+                              curve.getCtrlY() - n2[1],
+                              curve.getX2() - n2[0], 
+                              curve.getY2() - n2[1], true);
+
+        s = new QuadSegment(curve.getX1() - n1[0], curve.getY1() - n1[1],
+                            cp.getX(), cp.getY(),
+                            curve.getX2() - n2[0], curve.getY2() - n2[1]);
+      }
+
+    return s;
+  }
+
+  private Point2D lineIntersection(double X1, double Y1, 
+                                   double X2, double Y2, 
+                                   double X3, double Y3, 
+                                   double X4, double Y4,
+                                   boolean infinite)
+  {
+    double x1 = X1;
+    double y1 = Y1;
+    double rx = X2 - x1;
+    double ry = Y2 - y1;
+
+    double x2 = X3;
+    double y2 = Y3;
+    double sx = X4 - x2;
+    double sy = Y4 - y2;
+
+    double determinant = sx * ry - sy * rx;
+    double nom = (sx * (y2 - y1) + sy * (x1 - x2));
+
+    // lines can be considered parallel.
+    if (Math.abs(determinant) < 1E-6)
+      return null;
+
+    nom = nom / determinant;
+
+    // check if lines are within the bounds
+    if(!infinite && (nom > 1.0 || nom < 0.0))
+      return null;
+
+    return new Point2D.Double(x1 + nom * rx, y1 + nom * ry);
+  }
+
+  public void reverse()
+  {
+    Point2D p = P1;
+    P1 = P2;
+    P2 = p;
+  }
+
+  public double[] first()
+  {
+    return new double[]{cp.getX(), cp.getY()}; 
+  }
+
+  public double[] last()
+  {
+    return new double[]{cp.getX(), cp.getY()}; 
+  }
+}
diff --git a/gnu/java/awt/java2d/Segment.java b/gnu/java/awt/java2d/Segment.java
new file mode 100644
index 000000000..9a985f696
--- /dev/null
+++ b/gnu/java/awt/java2d/Segment.java
@@ -0,0 +1,131 @@
+/* Segment.java -- Abstract segment used for BasicStroke
+   Copyright (C) 2006 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath 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 for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package gnu.java.awt.java2d;
+
+import java.awt.geom.Point2D;
+
+public abstract class Segment implements Cloneable
+{
+  // segment type, PathIterator segment types are used.
+  public Point2D P1;
+  public Point2D P2;
+  public Segment next;
+  public Segment last;
+  protected double radius;
+
+  public Segment()
+  {
+    P1 = P2 = null;
+    next = null;
+    last = this;
+  }
+
+  public void add(Segment newsegment)
+  {
+    last.next = newsegment;
+    last = last.next;
+  }
+
+  /**
+   * Reverses the orientation of the whole polygon
+   */
+  public void reverseAll()
+  {
+    reverse();
+    Segment v = next;
+    Segment former = this;
+    next = null;
+
+    while (v != null)
+      {
+        v.reverse();
+        v.last = this;
+        Segment oldnext = v.next;
+        v.next = former;
+
+        former = v;
+        v = oldnext; // move to the next in list
+      }
+  }
+
+  public String toString()
+  {
+    return "Segment:"+P1+", "+P2;
+  }
+
+  /**
+   * Get the normal vector to the slope of the line.
+   * Returns: 0.5*width*(norm of derivative of the (x0,y0)-(x1,y1) vector)
+   */
+  protected double[] normal(double x0, double y0, double x1, double y1)
+  {
+    double dx = (x1 - x0);
+    double dy = (y1 - y0);
+    if( dy == 0 )
+      {
+        dy = radius * ((dx > 0)?1:-1);
+        dx = 0;
+      } 
+    else if( dx == 0 )
+      {
+        dx = radius * ((dy > 0)?-1:1);
+        dy = 0;
+      }
+    else
+      {
+        double N = Math.sqrt(dx * dx + dy * dy);
+        double odx = dx;
+        dx = -radius * dy / N;
+        dy = radius * odx / N;
+      }
+    return new double[]{ dx, dy };
+  }
+
+  public abstract void reverse();
+
+  /**
+   * Get the "top" and "bottom" segments of a segment.
+   * First array element is p0 + normal, second is p0 - normal.
+   */
+  public abstract Segment[] getDisplacedSegments(double radius);
+
+  public abstract double[] first();
+  public abstract double[] last();
+
+}