1 /* 2 * Copyright 2005 Google Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.google.common.geometry; 17 18 /** 19 * An S2Region represents a two-dimensional region over the unit sphere. It is 20 * an abstract interface with various concrete subtypes. 21 * 22 * The main purpose of this interface is to allow complex regions to be 23 * approximated as simpler regions. So rather than having a wide variety of 24 * virtual methods that are implemented by all subtypes, the interface is 25 * restricted to methods that are useful for computing approximations. 26 * 27 * 28 */ 29 public interface S2Region { 30 31 /** Return a bounding spherical cap. */ getCapBound()32 public abstract S2Cap getCapBound(); 33 34 35 /** Return a bounding latitude-longitude rectangle. */ getRectBound()36 public abstract S2LatLngRect getRectBound(); 37 38 /** 39 * If this method returns true, the region completely contains the given cell. 40 * Otherwise, either the region does not contain the cell or the containment 41 * relationship could not be determined. 42 */ contains(S2Cell cell)43 public abstract boolean contains(S2Cell cell); 44 45 /** 46 * If this method returns false, the region does not intersect the given cell. 47 * Otherwise, either region intersects the cell, or the intersection 48 * relationship could not be determined. 49 */ mayIntersect(S2Cell cell)50 public abstract boolean mayIntersect(S2Cell cell); 51 } 52