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Diffstat (limited to 'gcc-4.4.3/libjava/classpath/gnu/java/awt/java2d/QuadSegment.java')
| -rw-r--r-- | gcc-4.4.3/libjava/classpath/gnu/java/awt/java2d/QuadSegment.java | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/gcc-4.4.3/libjava/classpath/gnu/java/awt/java2d/QuadSegment.java b/gcc-4.4.3/libjava/classpath/gnu/java/awt/java2d/QuadSegment.java new file mode 100644 index 000000000..97a5372f6 --- /dev/null +++ b/gcc-4.4.3/libjava/classpath/gnu/java/awt/java2d/QuadSegment.java @@ -0,0 +1,260 @@ +/* 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() + { + QuadSegment segment = null; + + try + { + segment = (QuadSegment) super.clone(); + + segment.P1 = (Point2D) P1.clone(); + segment.P2 = (Point2D) P2.clone(); + segment.cp = (Point2D) cp.clone(); + } + catch (CloneNotSupportedException cnse) + { + InternalError ie = new InternalError(); + ie.initCause(cnse); + throw ie; + } + + return segment; + } + + /** + * 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) + { + n1[0] = -n1[0]; + n1[1] = -n1[1]; + n2[0] = -n2[0]; + n2[1] = -n2[1]; + } + + // Handle special cases where the control point is equal to an end point + // or end points are equal (ie, straight lines) + if (curve.getP1().equals(curve.getCtrlPt())) + { + cp = curve.getCtrlPt(); + cp.setLocation(cp.getX() + n2[0], cp.getY() + n2[1]); + n1[0] = n2[0]; + n1[1] = n2[1]; + } + else if (curve.getP2().equals(curve.getCtrlPt())) + { + cp = curve.getCtrlPt(); + cp.setLocation(cp.getX() + n1[0], cp.getY() + n1[1]); + n2[0] = n1[0]; + n2[1] = n1[1]; + } + else if (curve.getP1().equals(curve.getP2())) + { + cp = curve.getCtrlPt(); + + double deltaX = curve.getX1() - curve.getCtrlX(); + double deltaY = curve.getY1() - curve.getCtrlY(); + double length = Math.sqrt((deltaX * deltaX) + (deltaY * deltaY)); + double ratio = radius / length; + deltaX *= ratio; + deltaY *= ratio; + + if (plus) + cp.setLocation(cp.getX() + deltaX, cp.getY() + deltaY); + else + cp.setLocation(cp.getX() - deltaX, cp.getY() - deltaY); + } + else if (n1[0] == n2[0] && n1[1] == n2[1]) + { + cp = curve.getCtrlPt(); + cp.setLocation(cp.getX() + n1[0], cp.getY() + n1[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[] cp1() + { + return new double[]{cp.getX(), cp.getY()}; + } + + public double[] cp2() + { + return new double[]{cp.getX(), cp.getY()}; + } +} |