root / org.gvsig.jdk / trunk / org.gvsig.jdk / org.gvsig.jdk.v1_6 / src / main / java / org / gvsig / jdk / sun / awt / geom / Curve.java
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/*
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* Copyright 1998-2006 Sun Microsystems, Inc. All Rights Reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation. Sun designates this
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* particular file as subject to the "Classpath" exception as provided
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* by Sun in the LICENSE file that accompanied this code.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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* CA 95054 USA or visit www.sun.com if you need additional information or
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* have any questions.
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*/
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package org.gvsig.jdk.sun.awt.geom; |
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import java.awt.geom.IllegalPathStateException; |
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import java.awt.geom.PathIterator; |
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import java.awt.geom.Rectangle2D; |
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import java.util.Vector; |
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public abstract class Curve { |
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public static final int INCREASING = 1; |
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public static final int DECREASING = -1; |
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|
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protected int direction; |
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|
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public static void insertMove(Vector curves, double x, double y) { |
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curves.add(new Order0(x, y));
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} |
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|
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public static void insertLine(Vector curves, |
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double x0, double y0, |
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double x1, double y1) |
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{
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if (y0 < y1) {
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curves.add(new Order1(x0, y0,
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x1, y1, |
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INCREASING)); |
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} else if (y0 > y1) { |
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curves.add(new Order1(x1, y1,
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x0, y0, |
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DECREASING)); |
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} else {
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// Do not add horizontal lines
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} |
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} |
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|
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public static void insertQuad(Vector curves, |
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double x0, double y0, |
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double coords[]) |
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{
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double y1 = coords[3]; |
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if (y0 > y1) {
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Order2.insert(curves, coords, |
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coords[2], y1,
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coords[0], coords[1], |
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x0, y0, |
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DECREASING); |
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} else if (y0 == y1 && y0 == coords[1]) { |
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// Do not add horizontal lines
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return;
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} else {
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Order2.insert(curves, coords, |
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x0, y0, |
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coords[0], coords[1], |
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coords[2], y1,
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INCREASING); |
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} |
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} |
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|
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public static void insertCubic(Vector curves, |
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double x0, double y0, |
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double coords[]) |
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{
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double y1 = coords[5]; |
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if (y0 > y1) {
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Order3.insert(curves, coords, |
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coords[4], y1,
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coords[2], coords[3], |
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coords[0], coords[1], |
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x0, y0, |
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DECREASING); |
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} else if (y0 == y1 && y0 == coords[1] && y0 == coords[3]) { |
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// Do not add horizontal lines
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return;
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} else {
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Order3.insert(curves, coords, |
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x0, y0, |
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coords[0], coords[1], |
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coords[2], coords[3], |
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coords[4], y1,
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INCREASING); |
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} |
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} |
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|
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/**
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* Calculates the number of times the given path
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* crosses the ray extending to the right from (px,py).
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* If the point lies on a part of the path,
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* then no crossings are counted for that intersection.
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* +1 is added for each crossing where the Y coordinate is increasing
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* -1 is added for each crossing where the Y coordinate is decreasing
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* The return value is the sum of all crossings for every segment in
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* the path.
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* The path must start with a SEG_MOVETO, otherwise an exception is
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* thrown.
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* The caller must check p[xy] for NaN values.
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* The caller may also reject infinite p[xy] values as well.
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*/
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public static int pointCrossingsForPath(PathIterator pi, |
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double px, double py) |
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{
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if (pi.isDone()) {
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return 0; |
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} |
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double coords[] = new double[6]; |
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if (pi.currentSegment(coords) != PathIterator.SEG_MOVETO) { |
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throw new IllegalPathStateException("missing initial moveto "+ |
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"in path definition");
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} |
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pi.next(); |
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double movx = coords[0]; |
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double movy = coords[1]; |
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double curx = movx;
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double cury = movy;
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double endx, endy;
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int crossings = 0; |
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while (!pi.isDone()) {
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switch (pi.currentSegment(coords)) {
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case PathIterator.SEG_MOVETO: |
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if (cury != movy) {
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crossings += pointCrossingsForLine(px, py, |
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curx, cury, |
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movx, movy); |
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} |
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movx = curx = coords[0];
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movy = cury = coords[1];
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break;
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case PathIterator.SEG_LINETO: |
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endx = coords[0];
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endy = coords[1];
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crossings += pointCrossingsForLine(px, py, |
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curx, cury, |
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endx, endy); |
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curx = endx; |
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cury = endy; |
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break;
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case PathIterator.SEG_QUADTO: |
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endx = coords[2];
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endy = coords[3];
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crossings += pointCrossingsForQuad(px, py, |
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curx, cury, |
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coords[0], coords[1], |
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endx, endy, 0);
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curx = endx; |
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cury = endy; |
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break;
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case PathIterator.SEG_CUBICTO: |
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endx = coords[4];
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endy = coords[5];
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crossings += pointCrossingsForCubic(px, py, |
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curx, cury, |
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coords[0], coords[1], |
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coords[2], coords[3], |
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endx, endy, 0);
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curx = endx; |
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cury = endy; |
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break;
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case PathIterator.SEG_CLOSE: |
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if (cury != movy) {
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crossings += pointCrossingsForLine(px, py, |
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curx, cury, |
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movx, movy); |
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} |
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curx = movx; |
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cury = movy; |
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break;
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} |
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pi.next(); |
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} |
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if (cury != movy) {
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crossings += pointCrossingsForLine(px, py, |
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curx, cury, |
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movx, movy); |
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} |
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return crossings;
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} |
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/**
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* Calculates the number of times the line from (x0,y0) to (x1,y1)
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* crosses the ray extending to the right from (px,py).
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* If the point lies on the line, then no crossings are recorded.
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* +1 is returned for a crossing where the Y coordinate is increasing
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* -1 is returned for a crossing where the Y coordinate is decreasing
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*/
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public static int pointCrossingsForLine(double px, double py, |
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double x0, double y0, |
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double x1, double y1) |
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{
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if (py < y0 && py < y1) return 0; |
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if (py >= y0 && py >= y1) return 0; |
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// assert(y0 != y1);
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if (px >= x0 && px >= x1) return 0; |
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if (px < x0 && px < x1) return (y0 < y1) ? 1 : -1; |
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double xintercept = x0 + (py - y0) * (x1 - x0) / (y1 - y0);
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if (px >= xintercept) return 0; |
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return (y0 < y1) ? 1 : -1; |
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} |
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/**
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* Calculates the number of times the quad from (x0,y0) to (x1,y1)
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* crosses the ray extending to the right from (px,py).
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* If the point lies on a part of the curve,
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* then no crossings are counted for that intersection.
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* the level parameter should be 0 at the top-level call and will count
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* up for each recursion level to prevent infinite recursion
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* +1 is added for each crossing where the Y coordinate is increasing
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* -1 is added for each crossing where the Y coordinate is decreasing
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*/
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public static int pointCrossingsForQuad(double px, double py, |
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double x0, double y0, |
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double xc, double yc, |
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double x1, double y1, int level) |
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{
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if (py < y0 && py < yc && py < y1) return 0; |
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if (py >= y0 && py >= yc && py >= y1) return 0; |
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// Note y0 could equal y1...
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if (px >= x0 && px >= xc && px >= x1) return 0; |
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if (px < x0 && px < xc && px < x1) {
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if (py >= y0) {
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if (py < y1) return 1; |
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} else {
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// py < y0
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if (py >= y1) return -1; |
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} |
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// py outside of y01 range, and/or y0==y1
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return 0; |
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} |
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// double precision only has 52 bits of mantissa
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if (level > 52) return pointCrossingsForLine(px, py, x0, y0, x1, y1); |
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double x0c = (x0 + xc) / 2; |
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double y0c = (y0 + yc) / 2; |
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double xc1 = (xc + x1) / 2; |
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double yc1 = (yc + y1) / 2; |
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xc = (x0c + xc1) / 2;
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yc = (y0c + yc1) / 2;
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if (Double.isNaN(xc) || Double.isNaN(yc)) { |
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// [xy]c are NaN if any of [xy]0c or [xy]c1 are NaN
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// [xy]0c or [xy]c1 are NaN if any of [xy][0c1] are NaN
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// These values are also NaN if opposing infinities are added
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return 0; |
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} |
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return (pointCrossingsForQuad(px, py,
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x0, y0, x0c, y0c, xc, yc, |
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level+1) +
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pointCrossingsForQuad(px, py, |
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xc, yc, xc1, yc1, x1, y1, |
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level+1));
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} |
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/**
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* Calculates the number of times the cubic from (x0,y0) to (x1,y1)
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* crosses the ray extending to the right from (px,py).
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* If the point lies on a part of the curve,
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* then no crossings are counted for that intersection.
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* the level parameter should be 0 at the top-level call and will count
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* up for each recursion level to prevent infinite recursion
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* +1 is added for each crossing where the Y coordinate is increasing
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* -1 is added for each crossing where the Y coordinate is decreasing
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*/
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public static int pointCrossingsForCubic(double px, double py, |
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double x0, double y0, |
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double xc0, double yc0, |
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double xc1, double yc1, |
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double x1, double y1, int level) |
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{
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if (py < y0 && py < yc0 && py < yc1 && py < y1) return 0; |
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if (py >= y0 && py >= yc0 && py >= yc1 && py >= y1) return 0; |
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// Note y0 could equal yc0...
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if (px >= x0 && px >= xc0 && px >= xc1 && px >= x1) return 0; |
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if (px < x0 && px < xc0 && px < xc1 && px < x1) {
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if (py >= y0) {
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if (py < y1) return 1; |
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} else {
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// py < y0
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if (py >= y1) return -1; |
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} |
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// py outside of y01 range, and/or y0==yc0
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return 0; |
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} |
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// double precision only has 52 bits of mantissa
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if (level > 52) return pointCrossingsForLine(px, py, x0, y0, x1, y1); |
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double xmid = (xc0 + xc1) / 2; |
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double ymid = (yc0 + yc1) / 2; |
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xc0 = (x0 + xc0) / 2;
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yc0 = (y0 + yc0) / 2;
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xc1 = (xc1 + x1) / 2;
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yc1 = (yc1 + y1) / 2;
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double xc0m = (xc0 + xmid) / 2; |
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double yc0m = (yc0 + ymid) / 2; |
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double xmc1 = (xmid + xc1) / 2; |
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double ymc1 = (ymid + yc1) / 2; |
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xmid = (xc0m + xmc1) / 2;
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ymid = (yc0m + ymc1) / 2;
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if (Double.isNaN(xmid) || Double.isNaN(ymid)) { |
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// [xy]mid are NaN if any of [xy]c0m or [xy]mc1 are NaN
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// [xy]c0m or [xy]mc1 are NaN if any of [xy][c][01] are NaN
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// These values are also NaN if opposing infinities are added
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return 0; |
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} |
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return (pointCrossingsForCubic(px, py,
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x0, y0, xc0, yc0, |
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xc0m, yc0m, xmid, ymid, level+1) +
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pointCrossingsForCubic(px, py, |
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xmid, ymid, xmc1, ymc1, |
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xc1, yc1, x1, y1, level+1));
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} |
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/**
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* The rectangle intersection test counts the number of times
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* that the path crosses through the shadow that the rectangle
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* projects to the right towards (x => +INFINITY).
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*
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* During processing of the path it actually counts every time
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* the path crosses either or both of the top and bottom edges
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* of that shadow. If the path enters from the top, the count
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* is incremented. If it then exits back through the top, the
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* same way it came in, the count is decremented and there is
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* no impact on the winding count. If, instead, the path exits
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* out the bottom, then the count is incremented again and a
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* full pass through the shadow is indicated by the winding count
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* having been incremented by 2.
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*
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* Thus, the winding count that it accumulates is actually double
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* the real winding count. Since the path is continuous, the
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* final answer should be a multiple of 2, otherwise there is a
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* logic error somewhere.
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*
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* If the path ever has a direct hit on the rectangle, then a
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* special value is returned. This special value terminates
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* all ongoing accumulation on up through the call chain and
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* ends up getting returned to the calling function which can
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* then produce an answer directly. For intersection tests,
|
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* the answer is always "true" if the path intersects the
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* rectangle. For containment tests, the answer is always
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* "false" if the path intersects the rectangle. Thus, no
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* further processing is ever needed if an intersection occurs.
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*/
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public static final int RECT_INTERSECTS = 0x80000000; |
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|
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/**
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* Accumulate the number of times the path crosses the shadow
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* extending to the right of the rectangle. See the comment
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* for the RECT_INTERSECTS constant for more complete details.
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* The return value is the sum of all crossings for both the
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* top and bottom of the shadow for every segment in the path,
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* or the special value RECT_INTERSECTS if the path ever enters
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* the interior of the rectangle.
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* The path must start with a SEG_MOVETO, otherwise an exception is
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* thrown.
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* The caller must check r[xy]{min,max} for NaN values.
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*/
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public static int rectCrossingsForPath(PathIterator pi, |
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double rxmin, double rymin, |
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double rxmax, double rymax) |
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{
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if (rxmax <= rxmin || rymax <= rymin) {
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return 0; |
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} |
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if (pi.isDone()) {
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return 0; |
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} |
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double coords[] = new double[6]; |
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if (pi.currentSegment(coords) != PathIterator.SEG_MOVETO) { |
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throw new IllegalPathStateException("missing initial moveto "+ |
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"in path definition");
|
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} |
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pi.next(); |
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double curx, cury, movx, movy, endx, endy;
|
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curx = movx = coords[0];
|
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cury = movy = coords[1];
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int crossings = 0; |
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while (crossings != RECT_INTERSECTS && !pi.isDone()) {
|
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switch (pi.currentSegment(coords)) {
|
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case PathIterator.SEG_MOVETO: |
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if (curx != movx || cury != movy) {
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crossings = rectCrossingsForLine(crossings, |
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rxmin, rymin, |
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rxmax, rymax, |
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curx, cury, |
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movx, movy); |
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} |
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// Count should always be a multiple of 2 here.
|
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// assert((crossings & 1) != 0);
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movx = curx = coords[0];
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movy = cury = coords[1];
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break;
|
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case PathIterator.SEG_LINETO: |
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endx = coords[0];
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endy = coords[1];
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crossings = rectCrossingsForLine(crossings, |
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rxmin, rymin, |
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rxmax, rymax, |
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curx, cury, |
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endx, endy); |
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curx = endx; |
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cury = endy; |
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break;
|
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case PathIterator.SEG_QUADTO: |
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endx = coords[2];
|
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endy = coords[3];
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crossings = rectCrossingsForQuad(crossings, |
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rxmin, rymin, |
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rxmax, rymax, |
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curx, cury, |
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coords[0], coords[1], |
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endx, endy, 0);
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curx = endx; |
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cury = endy; |
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break;
|
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case PathIterator.SEG_CUBICTO: |
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endx = coords[4];
|
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endy = coords[5];
|
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crossings = rectCrossingsForCubic(crossings, |
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rxmin, rymin, |
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rxmax, rymax, |
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curx, cury, |
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coords[0], coords[1], |
| 441 |
coords[2], coords[3], |
| 442 |
endx, endy, 0);
|
| 443 |
curx = endx; |
| 444 |
cury = endy; |
| 445 |
break;
|
| 446 |
case PathIterator.SEG_CLOSE: |
| 447 |
if (curx != movx || cury != movy) {
|
| 448 |
crossings = rectCrossingsForLine(crossings, |
| 449 |
rxmin, rymin, |
| 450 |
rxmax, rymax, |
| 451 |
curx, cury, |
| 452 |
movx, movy); |
| 453 |
} |
| 454 |
curx = movx; |
| 455 |
cury = movy; |
| 456 |
// Count should always be a multiple of 2 here.
|
| 457 |
// assert((crossings & 1) != 0);
|
| 458 |
break;
|
| 459 |
} |
| 460 |
pi.next(); |
| 461 |
} |
| 462 |
if (crossings != RECT_INTERSECTS && (curx != movx || cury != movy)) {
|
| 463 |
crossings = rectCrossingsForLine(crossings, |
| 464 |
rxmin, rymin, |
| 465 |
rxmax, rymax, |
| 466 |
curx, cury, |
| 467 |
movx, movy); |
| 468 |
} |
| 469 |
// Count should always be a multiple of 2 here.
|
| 470 |
// assert((crossings & 1) != 0);
|
| 471 |
return crossings;
|
| 472 |
} |
| 473 |
|
| 474 |
/**
|
| 475 |
* Accumulate the number of times the line crosses the shadow
|
| 476 |
* extending to the right of the rectangle. See the comment
|
| 477 |
* for the RECT_INTERSECTS constant for more complete details.
|
| 478 |
*/
|
| 479 |
public static int rectCrossingsForLine(int crossings, |
| 480 |
double rxmin, double rymin, |
| 481 |
double rxmax, double rymax, |
| 482 |
double x0, double y0, |
| 483 |
double x1, double y1) |
| 484 |
{
|
| 485 |
if (y0 >= rymax && y1 >= rymax) return crossings; |
| 486 |
if (y0 <= rymin && y1 <= rymin) return crossings; |
| 487 |
if (x0 <= rxmin && x1 <= rxmin) return crossings; |
| 488 |
if (x0 >= rxmax && x1 >= rxmax) {
|
| 489 |
// Line is entirely to the right of the rect
|
| 490 |
// and the vertical ranges of the two overlap by a non-empty amount
|
| 491 |
// Thus, this line segment is partially in the "right-shadow"
|
| 492 |
// Path may have done a complete crossing
|
| 493 |
// Or path may have entered or exited the right-shadow
|
| 494 |
if (y0 < y1) {
|
| 495 |
// y-increasing line segment...
|
| 496 |
// We know that y0 < rymax and y1 > rymin
|
| 497 |
if (y0 <= rymin) crossings++;
|
| 498 |
if (y1 >= rymax) crossings++;
|
| 499 |
} else if (y1 < y0) { |
| 500 |
// y-decreasing line segment...
|
| 501 |
// We know that y1 < rymax and y0 > rymin
|
| 502 |
if (y1 <= rymin) crossings--;
|
| 503 |
if (y0 >= rymax) crossings--;
|
| 504 |
} |
| 505 |
return crossings;
|
| 506 |
} |
| 507 |
// Remaining case:
|
| 508 |
// Both x and y ranges overlap by a non-empty amount
|
| 509 |
// First do trivial INTERSECTS rejection of the cases
|
| 510 |
// where one of the endpoints is inside the rectangle.
|
| 511 |
if ((x0 > rxmin && x0 < rxmax && y0 > rymin && y0 < rymax) ||
|
| 512 |
(x1 > rxmin && x1 < rxmax && y1 > rymin && y1 < rymax)) |
| 513 |
{
|
| 514 |
return RECT_INTERSECTS;
|
| 515 |
} |
| 516 |
// Otherwise calculate the y intercepts and see where
|
| 517 |
// they fall with respect to the rectangle
|
| 518 |
double xi0 = x0;
|
| 519 |
if (y0 < rymin) {
|
| 520 |
xi0 += ((rymin - y0) * (x1 - x0) / (y1 - y0)); |
| 521 |
} else if (y0 > rymax) { |
| 522 |
xi0 += ((rymax - y0) * (x1 - x0) / (y1 - y0)); |
| 523 |
} |
| 524 |
double xi1 = x1;
|
| 525 |
if (y1 < rymin) {
|
| 526 |
xi1 += ((rymin - y1) * (x0 - x1) / (y0 - y1)); |
| 527 |
} else if (y1 > rymax) { |
| 528 |
xi1 += ((rymax - y1) * (x0 - x1) / (y0 - y1)); |
| 529 |
} |
| 530 |
if (xi0 <= rxmin && xi1 <= rxmin) return crossings; |
| 531 |
if (xi0 >= rxmax && xi1 >= rxmax) {
|
| 532 |
if (y0 < y1) {
|
| 533 |
// y-increasing line segment...
|
| 534 |
// We know that y0 < rymax and y1 > rymin
|
| 535 |
if (y0 <= rymin) crossings++;
|
| 536 |
if (y1 >= rymax) crossings++;
|
| 537 |
} else if (y1 < y0) { |
| 538 |
// y-decreasing line segment...
|
| 539 |
// We know that y1 < rymax and y0 > rymin
|
| 540 |
if (y1 <= rymin) crossings--;
|
| 541 |
if (y0 >= rymax) crossings--;
|
| 542 |
} |
| 543 |
return crossings;
|
| 544 |
} |
| 545 |
return RECT_INTERSECTS;
|
| 546 |
} |
| 547 |
|
| 548 |
/**
|
| 549 |
* Accumulate the number of times the quad crosses the shadow
|
| 550 |
* extending to the right of the rectangle. See the comment
|
| 551 |
* for the RECT_INTERSECTS constant for more complete details.
|
| 552 |
*/
|
| 553 |
public static int rectCrossingsForQuad(int crossings, |
| 554 |
double rxmin, double rymin, |
| 555 |
double rxmax, double rymax, |
| 556 |
double x0, double y0, |
| 557 |
double xc, double yc, |
| 558 |
double x1, double y1, |
| 559 |
int level)
|
| 560 |
{
|
| 561 |
if (y0 >= rymax && yc >= rymax && y1 >= rymax) return crossings; |
| 562 |
if (y0 <= rymin && yc <= rymin && y1 <= rymin) return crossings; |
| 563 |
if (x0 <= rxmin && xc <= rxmin && x1 <= rxmin) return crossings; |
| 564 |
if (x0 >= rxmax && xc >= rxmax && x1 >= rxmax) {
|
| 565 |
// Quad is entirely to the right of the rect
|
| 566 |
// and the vertical range of the 3 Y coordinates of the quad
|
| 567 |
// overlaps the vertical range of the rect by a non-empty amount
|
| 568 |
// We now judge the crossings solely based on the line segment
|
| 569 |
// connecting the endpoints of the quad.
|
| 570 |
// Note that we may have 0, 1, or 2 crossings as the control
|
| 571 |
// point may be causing the Y range intersection while the
|
| 572 |
// two endpoints are entirely above or below.
|
| 573 |
if (y0 < y1) {
|
| 574 |
// y-increasing line segment...
|
| 575 |
if (y0 <= rymin && y1 > rymin) crossings++;
|
| 576 |
if (y0 < rymax && y1 >= rymax) crossings++;
|
| 577 |
} else if (y1 < y0) { |
| 578 |
// y-decreasing line segment...
|
| 579 |
if (y1 <= rymin && y0 > rymin) crossings--;
|
| 580 |
if (y1 < rymax && y0 >= rymax) crossings--;
|
| 581 |
} |
| 582 |
return crossings;
|
| 583 |
} |
| 584 |
// The intersection of ranges is more complicated
|
| 585 |
// First do trivial INTERSECTS rejection of the cases
|
| 586 |
// where one of the endpoints is inside the rectangle.
|
| 587 |
if ((x0 < rxmax && x0 > rxmin && y0 < rymax && y0 > rymin) ||
|
| 588 |
(x1 < rxmax && x1 > rxmin && y1 < rymax && y1 > rymin)) |
| 589 |
{
|
| 590 |
return RECT_INTERSECTS;
|
| 591 |
} |
| 592 |
// Otherwise, subdivide and look for one of the cases above.
|
| 593 |
// double precision only has 52 bits of mantissa
|
| 594 |
if (level > 52) { |
| 595 |
return rectCrossingsForLine(crossings,
|
| 596 |
rxmin, rymin, rxmax, rymax, |
| 597 |
x0, y0, x1, y1); |
| 598 |
} |
| 599 |
double x0c = (x0 + xc) / 2; |
| 600 |
double y0c = (y0 + yc) / 2; |
| 601 |
double xc1 = (xc + x1) / 2; |
| 602 |
double yc1 = (yc + y1) / 2; |
| 603 |
xc = (x0c + xc1) / 2;
|
| 604 |
yc = (y0c + yc1) / 2;
|
| 605 |
if (Double.isNaN(xc) || Double.isNaN(yc)) { |
| 606 |
// [xy]c are NaN if any of [xy]0c or [xy]c1 are NaN
|
| 607 |
// [xy]0c or [xy]c1 are NaN if any of [xy][0c1] are NaN
|
| 608 |
// These values are also NaN if opposing infinities are added
|
| 609 |
return 0; |
| 610 |
} |
| 611 |
crossings = rectCrossingsForQuad(crossings, |
| 612 |
rxmin, rymin, rxmax, rymax, |
| 613 |
x0, y0, x0c, y0c, xc, yc, |
| 614 |
level+1);
|
| 615 |
if (crossings != RECT_INTERSECTS) {
|
| 616 |
crossings = rectCrossingsForQuad(crossings, |
| 617 |
rxmin, rymin, rxmax, rymax, |
| 618 |
xc, yc, xc1, yc1, x1, y1, |
| 619 |
level+1);
|
| 620 |
} |
| 621 |
return crossings;
|
| 622 |
} |
| 623 |
|
| 624 |
/**
|
| 625 |
* Accumulate the number of times the cubic crosses the shadow
|
| 626 |
* extending to the right of the rectangle. See the comment
|
| 627 |
* for the RECT_INTERSECTS constant for more complete details.
|
| 628 |
*/
|
| 629 |
public static int rectCrossingsForCubic(int crossings, |
| 630 |
double rxmin, double rymin, |
| 631 |
double rxmax, double rymax, |
| 632 |
double x0, double y0, |
| 633 |
double xc0, double yc0, |
| 634 |
double xc1, double yc1, |
| 635 |
double x1, double y1, |
| 636 |
int level)
|
| 637 |
{
|
| 638 |
if (y0 >= rymax && yc0 >= rymax && yc1 >= rymax && y1 >= rymax) {
|
| 639 |
return crossings;
|
| 640 |
} |
| 641 |
if (y0 <= rymin && yc0 <= rymin && yc1 <= rymin && y1 <= rymin) {
|
| 642 |
return crossings;
|
| 643 |
} |
| 644 |
if (x0 <= rxmin && xc0 <= rxmin && xc1 <= rxmin && x1 <= rxmin) {
|
| 645 |
return crossings;
|
| 646 |
} |
| 647 |
if (x0 >= rxmax && xc0 >= rxmax && xc1 >= rxmax && x1 >= rxmax) {
|
| 648 |
// Cubic is entirely to the right of the rect
|
| 649 |
// and the vertical range of the 4 Y coordinates of the cubic
|
| 650 |
// overlaps the vertical range of the rect by a non-empty amount
|
| 651 |
// We now judge the crossings solely based on the line segment
|
| 652 |
// connecting the endpoints of the cubic.
|
| 653 |
// Note that we may have 0, 1, or 2 crossings as the control
|
| 654 |
// points may be causing the Y range intersection while the
|
| 655 |
// two endpoints are entirely above or below.
|
| 656 |
if (y0 < y1) {
|
| 657 |
// y-increasing line segment...
|
| 658 |
if (y0 <= rymin && y1 > rymin) crossings++;
|
| 659 |
if (y0 < rymax && y1 >= rymax) crossings++;
|
| 660 |
} else if (y1 < y0) { |
| 661 |
// y-decreasing line segment...
|
| 662 |
if (y1 <= rymin && y0 > rymin) crossings--;
|
| 663 |
if (y1 < rymax && y0 >= rymax) crossings--;
|
| 664 |
} |
| 665 |
return crossings;
|
| 666 |
} |
| 667 |
// The intersection of ranges is more complicated
|
| 668 |
// First do trivial INTERSECTS rejection of the cases
|
| 669 |
// where one of the endpoints is inside the rectangle.
|
| 670 |
if ((x0 > rxmin && x0 < rxmax && y0 > rymin && y0 < rymax) ||
|
| 671 |
(x1 > rxmin && x1 < rxmax && y1 > rymin && y1 < rymax)) |
| 672 |
{
|
| 673 |
return RECT_INTERSECTS;
|
| 674 |
} |
| 675 |
// Otherwise, subdivide and look for one of the cases above.
|
| 676 |
// double precision only has 52 bits of mantissa
|
| 677 |
if (level > 52) { |
| 678 |
return rectCrossingsForLine(crossings,
|
| 679 |
rxmin, rymin, rxmax, rymax, |
| 680 |
x0, y0, x1, y1); |
| 681 |
} |
| 682 |
double xmid = (xc0 + xc1) / 2; |
| 683 |
double ymid = (yc0 + yc1) / 2; |
| 684 |
xc0 = (x0 + xc0) / 2;
|
| 685 |
yc0 = (y0 + yc0) / 2;
|
| 686 |
xc1 = (xc1 + x1) / 2;
|
| 687 |
yc1 = (yc1 + y1) / 2;
|
| 688 |
double xc0m = (xc0 + xmid) / 2; |
| 689 |
double yc0m = (yc0 + ymid) / 2; |
| 690 |
double xmc1 = (xmid + xc1) / 2; |
| 691 |
double ymc1 = (ymid + yc1) / 2; |
| 692 |
xmid = (xc0m + xmc1) / 2;
|
| 693 |
ymid = (yc0m + ymc1) / 2;
|
| 694 |
if (Double.isNaN(xmid) || Double.isNaN(ymid)) { |
| 695 |
// [xy]mid are NaN if any of [xy]c0m or [xy]mc1 are NaN
|
| 696 |
// [xy]c0m or [xy]mc1 are NaN if any of [xy][c][01] are NaN
|
| 697 |
// These values are also NaN if opposing infinities are added
|
| 698 |
return 0; |
| 699 |
} |
| 700 |
crossings = rectCrossingsForCubic(crossings, |
| 701 |
rxmin, rymin, rxmax, rymax, |
| 702 |
x0, y0, xc0, yc0, |
| 703 |
xc0m, yc0m, xmid, ymid, level+1);
|
| 704 |
if (crossings != RECT_INTERSECTS) {
|
| 705 |
crossings = rectCrossingsForCubic(crossings, |
| 706 |
rxmin, rymin, rxmax, rymax, |
| 707 |
xmid, ymid, xmc1, ymc1, |
| 708 |
xc1, yc1, x1, y1, level+1);
|
| 709 |
} |
| 710 |
return crossings;
|
| 711 |
} |
| 712 |
|
| 713 |
Curve(int direction) {
|
| 714 |
this.direction = direction;
|
| 715 |
} |
| 716 |
|
| 717 |
public final int getDirection() { |
| 718 |
return direction;
|
| 719 |
} |
| 720 |
|
| 721 |
public final Curve getWithDirection(int direction) { |
| 722 |
return (this.direction == direction ? this : getReversedCurve()); |
| 723 |
} |
| 724 |
|
| 725 |
public static double round(double v) { |
| 726 |
//return Math.rint(v*10)/10;
|
| 727 |
return v;
|
| 728 |
} |
| 729 |
|
| 730 |
public static int orderof(double x1, double x2) { |
| 731 |
if (x1 < x2) {
|
| 732 |
return -1; |
| 733 |
} |
| 734 |
if (x1 > x2) {
|
| 735 |
return 1; |
| 736 |
} |
| 737 |
return 0; |
| 738 |
} |
| 739 |
|
| 740 |
public static long signeddiffbits(double y1, double y2) { |
| 741 |
return (Double.doubleToLongBits(y1) - Double.doubleToLongBits(y2)); |
| 742 |
} |
| 743 |
public static long diffbits(double y1, double y2) { |
| 744 |
return Math.abs(Double.doubleToLongBits(y1) - |
| 745 |
Double.doubleToLongBits(y2));
|
| 746 |
} |
| 747 |
public static double prev(double v) { |
| 748 |
return Double.longBitsToDouble(Double.doubleToLongBits(v)-1); |
| 749 |
} |
| 750 |
public static double next(double v) { |
| 751 |
return Double.longBitsToDouble(Double.doubleToLongBits(v)+1); |
| 752 |
} |
| 753 |
|
| 754 |
public String toString() { |
| 755 |
return ("Curve["+ |
| 756 |
getOrder()+", "+
|
| 757 |
("("+round(getX0())+", "+round(getY0())+"), ")+ |
| 758 |
controlPointString()+ |
| 759 |
("("+round(getX1())+", "+round(getY1())+"), ")+ |
| 760 |
(direction == INCREASING ? "D" : "U")+ |
| 761 |
"]");
|
| 762 |
} |
| 763 |
|
| 764 |
public String controlPointString() { |
| 765 |
return ""; |
| 766 |
} |
| 767 |
|
| 768 |
public abstract int getOrder(); |
| 769 |
|
| 770 |
public abstract double getXTop(); |
| 771 |
public abstract double getYTop(); |
| 772 |
public abstract double getXBot(); |
| 773 |
public abstract double getYBot(); |
| 774 |
|
| 775 |
public abstract double getXMin(); |
| 776 |
public abstract double getXMax(); |
| 777 |
|
| 778 |
public abstract double getX0(); |
| 779 |
public abstract double getY0(); |
| 780 |
public abstract double getX1(); |
| 781 |
public abstract double getY1(); |
| 782 |
|
| 783 |
public abstract double XforY(double y); |
| 784 |
public abstract double TforY(double y); |
| 785 |
public abstract double XforT(double t); |
| 786 |
public abstract double YforT(double t); |
| 787 |
public abstract double dXforT(double t, int deriv); |
| 788 |
public abstract double dYforT(double t, int deriv); |
| 789 |
|
| 790 |
public abstract double nextVertical(double t0, double t1); |
| 791 |
|
| 792 |
public int crossingsFor(double x, double y) { |
| 793 |
if (y >= getYTop() && y < getYBot()) {
|
| 794 |
if (x < getXMax() && (x < getXMin() || x < XforY(y))) {
|
| 795 |
return 1; |
| 796 |
} |
| 797 |
} |
| 798 |
return 0; |
| 799 |
} |
| 800 |
|
| 801 |
public boolean accumulateCrossings(Crossings c) { |
| 802 |
double xhi = c.getXHi();
|
| 803 |
if (getXMin() >= xhi) {
|
| 804 |
return false; |
| 805 |
} |
| 806 |
double xlo = c.getXLo();
|
| 807 |
double ylo = c.getYLo();
|
| 808 |
double yhi = c.getYHi();
|
| 809 |
double y0 = getYTop();
|
| 810 |
double y1 = getYBot();
|
| 811 |
double tstart, ystart, tend, yend;
|
| 812 |
if (y0 < ylo) {
|
| 813 |
if (y1 <= ylo) {
|
| 814 |
return false; |
| 815 |
} |
| 816 |
ystart = ylo; |
| 817 |
tstart = TforY(ylo); |
| 818 |
} else {
|
| 819 |
if (y0 >= yhi) {
|
| 820 |
return false; |
| 821 |
} |
| 822 |
ystart = y0; |
| 823 |
tstart = 0;
|
| 824 |
} |
| 825 |
if (y1 > yhi) {
|
| 826 |
yend = yhi; |
| 827 |
tend = TforY(yhi); |
| 828 |
} else {
|
| 829 |
yend = y1; |
| 830 |
tend = 1;
|
| 831 |
} |
| 832 |
boolean hitLo = false; |
| 833 |
boolean hitHi = false; |
| 834 |
while (true) { |
| 835 |
double x = XforT(tstart);
|
| 836 |
if (x < xhi) {
|
| 837 |
if (hitHi || x > xlo) {
|
| 838 |
return true; |
| 839 |
} |
| 840 |
hitLo = true;
|
| 841 |
} else {
|
| 842 |
if (hitLo) {
|
| 843 |
return true; |
| 844 |
} |
| 845 |
hitHi = true;
|
| 846 |
} |
| 847 |
if (tstart >= tend) {
|
| 848 |
break;
|
| 849 |
} |
| 850 |
tstart = nextVertical(tstart, tend); |
| 851 |
} |
| 852 |
if (hitLo) {
|
| 853 |
c.record(ystart, yend, direction); |
| 854 |
} |
| 855 |
return false; |
| 856 |
} |
| 857 |
|
| 858 |
public abstract void enlarge(Rectangle2D r); |
| 859 |
|
| 860 |
public Curve getSubCurve(double ystart, double yend) { |
| 861 |
return getSubCurve(ystart, yend, direction);
|
| 862 |
} |
| 863 |
|
| 864 |
public abstract Curve getReversedCurve(); |
| 865 |
public abstract Curve getSubCurve(double ystart, double yend, int dir); |
| 866 |
|
| 867 |
public int compareTo(Curve that, double yrange[]) { |
| 868 |
/*
|
| 869 |
System.out.println(this+".compareTo("+that+")");
|
| 870 |
System.out.println("target range = "+yrange[0]+"=>"+yrange[1]);
|
| 871 |
*/
|
| 872 |
double y0 = yrange[0]; |
| 873 |
double y1 = yrange[1]; |
| 874 |
y1 = Math.min(Math.min(y1, this.getYBot()), that.getYBot()); |
| 875 |
if (y1 <= yrange[0]) { |
| 876 |
System.err.println("this == "+this); |
| 877 |
System.err.println("that == "+that); |
| 878 |
System.out.println("target range = "+yrange[0]+"=>"+yrange[1]); |
| 879 |
throw new InternalError("backstepping from "+yrange[0]+" to "+y1); |
| 880 |
} |
| 881 |
yrange[1] = y1;
|
| 882 |
if (this.getXMax() <= that.getXMin()) { |
| 883 |
if (this.getXMin() == that.getXMax()) { |
| 884 |
return 0; |
| 885 |
} |
| 886 |
return -1; |
| 887 |
} |
| 888 |
if (this.getXMin() >= that.getXMax()) { |
| 889 |
return 1; |
| 890 |
} |
| 891 |
// Parameter s for thi(s) curve and t for tha(t) curve
|
| 892 |
// [st]0 = parameters for top of current section of interest
|
| 893 |
// [st]1 = parameters for bottom of valid range
|
| 894 |
// [st]h = parameters for hypothesis point
|
| 895 |
// [d][xy]s = valuations of thi(s) curve at sh
|
| 896 |
// [d][xy]t = valuations of tha(t) curve at th
|
| 897 |
double s0 = this.TforY(y0); |
| 898 |
double ys0 = this.YforT(s0); |
| 899 |
if (ys0 < y0) {
|
| 900 |
s0 = refineTforY(s0, ys0, y0); |
| 901 |
ys0 = this.YforT(s0);
|
| 902 |
} |
| 903 |
double s1 = this.TforY(y1); |
| 904 |
if (this.YforT(s1) < y0) { |
| 905 |
s1 = refineTforY(s1, this.YforT(s1), y0);
|
| 906 |
//System.out.println("s1 problem!");
|
| 907 |
} |
| 908 |
double t0 = that.TforY(y0);
|
| 909 |
double yt0 = that.YforT(t0);
|
| 910 |
if (yt0 < y0) {
|
| 911 |
t0 = that.refineTforY(t0, yt0, y0); |
| 912 |
yt0 = that.YforT(t0); |
| 913 |
} |
| 914 |
double t1 = that.TforY(y1);
|
| 915 |
if (that.YforT(t1) < y0) {
|
| 916 |
t1 = that.refineTforY(t1, that.YforT(t1), y0); |
| 917 |
//System.out.println("t1 problem!");
|
| 918 |
} |
| 919 |
double xs0 = this.XforT(s0); |
| 920 |
double xt0 = that.XforT(t0);
|
| 921 |
double scale = Math.max(Math.abs(y0), Math.abs(y1)); |
| 922 |
double ymin = Math.max(scale * 1E-14, 1E-300); |
| 923 |
if (fairlyClose(xs0, xt0)) {
|
| 924 |
double bump = ymin;
|
| 925 |
double maxbump = Math.min(ymin * 1E13, (y1 - y0) * .1); |
| 926 |
double y = y0 + bump;
|
| 927 |
while (y <= y1) {
|
| 928 |
if (fairlyClose(this.XforY(y), that.XforY(y))) { |
| 929 |
if ((bump *= 2) > maxbump) { |
| 930 |
bump = maxbump; |
| 931 |
} |
| 932 |
} else {
|
| 933 |
y -= bump; |
| 934 |
while (true) { |
| 935 |
bump /= 2;
|
| 936 |
double newy = y + bump;
|
| 937 |
if (newy <= y) {
|
| 938 |
break;
|
| 939 |
} |
| 940 |
if (fairlyClose(this.XforY(newy), that.XforY(newy))) { |
| 941 |
y = newy; |
| 942 |
} |
| 943 |
} |
| 944 |
break;
|
| 945 |
} |
| 946 |
y += bump; |
| 947 |
} |
| 948 |
if (y > y0) {
|
| 949 |
if (y < y1) {
|
| 950 |
yrange[1] = y;
|
| 951 |
} |
| 952 |
return 0; |
| 953 |
} |
| 954 |
} |
| 955 |
//double ymin = y1 * 1E-14;
|
| 956 |
if (ymin <= 0) { |
| 957 |
System.out.println("ymin = "+ymin); |
| 958 |
} |
| 959 |
/*
|
| 960 |
System.out.println("s range = "+s0+" to "+s1);
|
| 961 |
System.out.println("t range = "+t0+" to "+t1);
|
| 962 |
*/
|
| 963 |
while (s0 < s1 && t0 < t1) {
|
| 964 |
double sh = this.nextVertical(s0, s1); |
| 965 |
double xsh = this.XforT(sh); |
| 966 |
double ysh = this.YforT(sh); |
| 967 |
double th = that.nextVertical(t0, t1);
|
| 968 |
double xth = that.XforT(th);
|
| 969 |
double yth = that.YforT(th);
|
| 970 |
/*
|
| 971 |
System.out.println("sh = "+sh);
|
| 972 |
System.out.println("th = "+th);
|
| 973 |
*/
|
| 974 |
try {
|
| 975 |
if (findIntersect(that, yrange, ymin, 0, 0, |
| 976 |
s0, xs0, ys0, sh, xsh, ysh, |
| 977 |
t0, xt0, yt0, th, xth, yth)) {
|
| 978 |
break;
|
| 979 |
} |
| 980 |
} catch (Throwable t) { |
| 981 |
System.err.println("Error: "+t); |
| 982 |
System.err.println("y range was "+yrange[0]+"=>"+yrange[1]); |
| 983 |
System.err.println("s y range is "+ys0+"=>"+ysh); |
| 984 |
System.err.println("t y range is "+yt0+"=>"+yth); |
| 985 |
System.err.println("ymin is "+ymin); |
| 986 |
return 0; |
| 987 |
} |
| 988 |
if (ysh < yth) {
|
| 989 |
if (ysh > yrange[0]) { |
| 990 |
if (ysh < yrange[1]) { |
| 991 |
yrange[1] = ysh;
|
| 992 |
} |
| 993 |
break;
|
| 994 |
} |
| 995 |
s0 = sh; |
| 996 |
xs0 = xsh; |
| 997 |
ys0 = ysh; |
| 998 |
} else {
|
| 999 |
if (yth > yrange[0]) { |
| 1000 |
if (yth < yrange[1]) { |
| 1001 |
yrange[1] = yth;
|
| 1002 |
} |
| 1003 |
break;
|
| 1004 |
} |
| 1005 |
t0 = th; |
| 1006 |
xt0 = xth; |
| 1007 |
yt0 = yth; |
| 1008 |
} |
| 1009 |
} |
| 1010 |
double ymid = (yrange[0] + yrange[1]) / 2; |
| 1011 |
/*
|
| 1012 |
System.out.println("final this["+s0+", "+sh+", "+s1+"]");
|
| 1013 |
System.out.println("final y["+ys0+", "+ysh+"]");
|
| 1014 |
System.out.println("final that["+t0+", "+th+", "+t1+"]");
|
| 1015 |
System.out.println("final y["+yt0+", "+yth+"]");
|
| 1016 |
System.out.println("final order = "+orderof(this.XforY(ymid),
|
| 1017 |
that.XforY(ymid)));
|
| 1018 |
System.out.println("final range = "+yrange[0]+"=>"+yrange[1]);
|
| 1019 |
*/
|
| 1020 |
/*
|
| 1021 |
System.out.println("final sx = "+this.XforY(ymid));
|
| 1022 |
System.out.println("final tx = "+that.XforY(ymid));
|
| 1023 |
System.out.println("final order = "+orderof(this.XforY(ymid),
|
| 1024 |
that.XforY(ymid)));
|
| 1025 |
*/
|
| 1026 |
return orderof(this.XforY(ymid), that.XforY(ymid)); |
| 1027 |
} |
| 1028 |
|
| 1029 |
public static final double TMIN = 1E-3; |
| 1030 |
|
| 1031 |
public boolean findIntersect(Curve that, double yrange[], double ymin, |
| 1032 |
int slevel, int tlevel, |
| 1033 |
double s0, double xs0, double ys0, |
| 1034 |
double s1, double xs1, double ys1, |
| 1035 |
double t0, double xt0, double yt0, |
| 1036 |
double t1, double xt1, double yt1) |
| 1037 |
{
|
| 1038 |
/*
|
| 1039 |
String pad = " ";
|
| 1040 |
pad = pad+pad+pad+pad+pad;
|
| 1041 |
pad = pad+pad;
|
| 1042 |
System.out.println("----------------------------------------------");
|
| 1043 |
System.out.println(pad.substring(0, slevel)+ys0);
|
| 1044 |
System.out.println(pad.substring(0, slevel)+ys1);
|
| 1045 |
System.out.println(pad.substring(0, slevel)+(s1-s0));
|
| 1046 |
System.out.println("-------");
|
| 1047 |
System.out.println(pad.substring(0, tlevel)+yt0);
|
| 1048 |
System.out.println(pad.substring(0, tlevel)+yt1);
|
| 1049 |
System.out.println(pad.substring(0, tlevel)+(t1-t0));
|
| 1050 |
*/
|
| 1051 |
if (ys0 > yt1 || yt0 > ys1) {
|
| 1052 |
return false; |
| 1053 |
} |
| 1054 |
if (Math.min(xs0, xs1) > Math.max(xt0, xt1) || |
| 1055 |
Math.max(xs0, xs1) < Math.min(xt0, xt1)) |
| 1056 |
{
|
| 1057 |
return false; |
| 1058 |
} |
| 1059 |
// Bounding boxes intersect - back off the larger of
|
| 1060 |
// the two subcurves by half until they stop intersecting
|
| 1061 |
// (or until they get small enough to switch to a more
|
| 1062 |
// intensive algorithm).
|
| 1063 |
if (s1 - s0 > TMIN) {
|
| 1064 |
double s = (s0 + s1) / 2; |
| 1065 |
double xs = this.XforT(s); |
| 1066 |
double ys = this.YforT(s); |
| 1067 |
if (s == s0 || s == s1) {
|
| 1068 |
System.out.println("s0 = "+s0); |
| 1069 |
System.out.println("s1 = "+s1); |
| 1070 |
throw new InternalError("no s progress!"); |
| 1071 |
} |
| 1072 |
if (t1 - t0 > TMIN) {
|
| 1073 |
double t = (t0 + t1) / 2; |
| 1074 |
double xt = that.XforT(t);
|
| 1075 |
double yt = that.YforT(t);
|
| 1076 |
if (t == t0 || t == t1) {
|
| 1077 |
System.out.println("t0 = "+t0); |
| 1078 |
System.out.println("t1 = "+t1); |
| 1079 |
throw new InternalError("no t progress!"); |
| 1080 |
} |
| 1081 |
if (ys >= yt0 && yt >= ys0) {
|
| 1082 |
if (findIntersect(that, yrange, ymin, slevel+1, tlevel+1, |
| 1083 |
s0, xs0, ys0, s, xs, ys, |
| 1084 |
t0, xt0, yt0, t, xt, yt)) {
|
| 1085 |
return true; |
| 1086 |
} |
| 1087 |
} |
| 1088 |
if (ys >= yt) {
|
| 1089 |
if (findIntersect(that, yrange, ymin, slevel+1, tlevel+1, |
| 1090 |
s0, xs0, ys0, s, xs, ys, |
| 1091 |
t, xt, yt, t1, xt1, yt1)) {
|
| 1092 |
return true; |
| 1093 |
} |
| 1094 |
} |
| 1095 |
if (yt >= ys) {
|
| 1096 |
if (findIntersect(that, yrange, ymin, slevel+1, tlevel+1, |
| 1097 |
s, xs, ys, s1, xs1, ys1, |
| 1098 |
t0, xt0, yt0, t, xt, yt)) {
|
| 1099 |
return true; |
| 1100 |
} |
| 1101 |
} |
| 1102 |
if (ys1 >= yt && yt1 >= ys) {
|
| 1103 |
if (findIntersect(that, yrange, ymin, slevel+1, tlevel+1, |
| 1104 |
s, xs, ys, s1, xs1, ys1, |
| 1105 |
t, xt, yt, t1, xt1, yt1)) {
|
| 1106 |
return true; |
| 1107 |
} |
| 1108 |
} |
| 1109 |
} else {
|
| 1110 |
if (ys >= yt0) {
|
| 1111 |
if (findIntersect(that, yrange, ymin, slevel+1, tlevel, |
| 1112 |
s0, xs0, ys0, s, xs, ys, |
| 1113 |
t0, xt0, yt0, t1, xt1, yt1)) {
|
| 1114 |
return true; |
| 1115 |
} |
| 1116 |
} |
| 1117 |
if (yt1 >= ys) {
|
| 1118 |
if (findIntersect(that, yrange, ymin, slevel+1, tlevel, |
| 1119 |
s, xs, ys, s1, xs1, ys1, |
| 1120 |
t0, xt0, yt0, t1, xt1, yt1)) {
|
| 1121 |
return true; |
| 1122 |
} |
| 1123 |
} |
| 1124 |
} |
| 1125 |
} else if (t1 - t0 > TMIN) { |
| 1126 |
double t = (t0 + t1) / 2; |
| 1127 |
double xt = that.XforT(t);
|
| 1128 |
double yt = that.YforT(t);
|
| 1129 |
if (t == t0 || t == t1) {
|
| 1130 |
System.out.println("t0 = "+t0); |
| 1131 |
System.out.println("t1 = "+t1); |
| 1132 |
throw new InternalError("no t progress!"); |
| 1133 |
} |
| 1134 |
if (yt >= ys0) {
|
| 1135 |
if (findIntersect(that, yrange, ymin, slevel, tlevel+1, |
| 1136 |
s0, xs0, ys0, s1, xs1, ys1, |
| 1137 |
t0, xt0, yt0, t, xt, yt)) {
|
| 1138 |
return true; |
| 1139 |
} |
| 1140 |
} |
| 1141 |
if (ys1 >= yt) {
|
| 1142 |
if (findIntersect(that, yrange, ymin, slevel, tlevel+1, |
| 1143 |
s0, xs0, ys0, s1, xs1, ys1, |
| 1144 |
t, xt, yt, t1, xt1, yt1)) {
|
| 1145 |
return true; |
| 1146 |
} |
| 1147 |
} |
| 1148 |
} else {
|
| 1149 |
// No more subdivisions
|
| 1150 |
double xlk = xs1 - xs0;
|
| 1151 |
double ylk = ys1 - ys0;
|
| 1152 |
double xnm = xt1 - xt0;
|
| 1153 |
double ynm = yt1 - yt0;
|
| 1154 |
double xmk = xt0 - xs0;
|
| 1155 |
double ymk = yt0 - ys0;
|
| 1156 |
double det = xnm * ylk - ynm * xlk;
|
| 1157 |
if (det != 0) { |
| 1158 |
double detinv = 1 / det; |
| 1159 |
double s = (xnm * ymk - ynm * xmk) * detinv;
|
| 1160 |
double t = (xlk * ymk - ylk * xmk) * detinv;
|
| 1161 |
if (s >= 0 && s <= 1 && t >= 0 && t <= 1) { |
| 1162 |
s = s0 + s * (s1 - s0); |
| 1163 |
t = t0 + t * (t1 - t0); |
| 1164 |
if (s < 0 || s > 1 || t < 0 || t > 1) { |
| 1165 |
System.out.println("Uh oh!"); |
| 1166 |
} |
| 1167 |
double y = (this.YforT(s) + that.YforT(t)) / 2; |
| 1168 |
if (y <= yrange[1] && y > yrange[0]) { |
| 1169 |
yrange[1] = y;
|
| 1170 |
return true; |
| 1171 |
} |
| 1172 |
} |
| 1173 |
} |
| 1174 |
//System.out.println("Testing lines!");
|
| 1175 |
} |
| 1176 |
return false; |
| 1177 |
} |
| 1178 |
|
| 1179 |
public double refineTforY(double t0, double yt0, double y0) { |
| 1180 |
double t1 = 1; |
| 1181 |
while (true) { |
| 1182 |
double th = (t0 + t1) / 2; |
| 1183 |
if (th == t0 || th == t1) {
|
| 1184 |
return t1;
|
| 1185 |
} |
| 1186 |
double y = YforT(th);
|
| 1187 |
if (y < y0) {
|
| 1188 |
t0 = th; |
| 1189 |
yt0 = y; |
| 1190 |
} else if (y > y0) { |
| 1191 |
t1 = th; |
| 1192 |
} else {
|
| 1193 |
return t1;
|
| 1194 |
} |
| 1195 |
} |
| 1196 |
} |
| 1197 |
|
| 1198 |
public boolean fairlyClose(double v1, double v2) { |
| 1199 |
return (Math.abs(v1 - v2) < |
| 1200 |
Math.max(Math.abs(v1), Math.abs(v2)) * 1E-10); |
| 1201 |
} |
| 1202 |
|
| 1203 |
public abstract int getSegment(double coords[]); |
| 1204 |
} |