001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.commons.geometry.examples.tutorials.bsp; 018 019import java.io.File; 020import java.util.Arrays; 021 022import org.apache.commons.geometry.euclidean.twod.Bounds2D; 023import org.apache.commons.geometry.euclidean.twod.RegionBSPTree2D; 024import org.apache.commons.geometry.euclidean.twod.Vector2D; 025import org.apache.commons.geometry.euclidean.twod.path.LinePath; 026import org.apache.commons.numbers.core.Precision; 027 028/** Class containing tutorial code for computing the union of two trees. 029 */ 030public final class BSPTreeUnion { 031 032 /** No instantiation. */ 033 private BSPTreeUnion() {} 034 035 /** Tutorial code entry point. 036 * @param args command arguments; if given, the first argument is used as the location of 037 * output folder 038 */ 039 public static void main(final String[] args) { 040 final File outputFolder = new File(args.length > 0 ? args[0] : "."); 041 final BSPTreeSVGWriter svgWriter = new BSPTreeSVGWriter(Bounds2D.from(Vector2D.of(-8, -8), Vector2D.of(8, 8))); 042 043 final Precision.DoubleEquivalence precision = Precision.doubleEquivalenceOfEpsilon(1e-6); 044 045 final RegionBSPTree2D a = LinePath.fromVertexLoop(Arrays.asList( 046 Vector2D.of(2, 0), 047 Vector2D.of(-4, 3), 048 Vector2D.of(-4, -3) 049 ), precision).toTree(); 050 051 final RegionBSPTree2D b = LinePath.fromVertexLoop(Arrays.asList( 052 Vector2D.of(-2, 0), 053 Vector2D.of(4, -3), 054 Vector2D.of(4, 3) 055 ), precision).toTree(); 056 057 final RegionBSPTree2D result = RegionBSPTree2D.empty(); 058 059 result.union(a, b); 060 061 svgWriter.write(result, new File(outputFolder, "union.svg")); 062 } 063}