/******************************************************************************* * Copyright 2011 See AUTHORS file. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. ******************************************************************************/ package com.badlogic.gdx.physics.box2d; /** * A shape is used for collision detection. You can create a shape however you like. Shapes used for simulation in b2World are * created automatically when a b2Fixture is created. * * NOTE: YOU NEED TO DISPOSE SHAPES AFTER YOU NO LONGER USE THEM! E.g. after calling body.createFixture(); * @author mzechner * */ public abstract class Shape { /** * Enum describing the type of a shape * @author mzechner * */ public enum Type { Circle, Polygon, }; /** the address of the shape **/ protected long addr; /** * Get the type of this shape. You can use this to down cast to the concrete shape. * @return the shape type. */ public abstract Type getType (); /** * Returns the radius of this shape */ public float getRadius () { return jniGetRadius(addr); } private native float jniGetRadius (long addr); /** * Sets the radius of this shape */ public void setRadius (float radius) { jniSetRadius(addr, radius); } private native void jniSetRadius (long addr, float radius); /** * Needs to be called when the shape is no longer used, e.g. after a fixture was created based on the shape. */ public void dispose () { jniDispose(addr); } private native void jniDispose (long addr); protected static native int jniGetType (long addr); // /// Test a point for containment in this shape. This only works for convex shapes. // /// @param xf the shape world transform. // /// @param p a point in world coordinates. // virtual bool TestPoint(const b2Transform& xf, const b2Vec2& p) const = 0; // // /// Cast a ray against this shape. // /// @param output the ray-cast results. // /// @param input the ray-cast input parameters. // /// @param transform the transform to be applied to the shape. // virtual bool RayCast(b2RayCastOutput* output, const b2RayCastInput& input, const b2Transform& transform) const = 0; // // /// Given a transform, compute the associated axis aligned bounding box for this shape. // /// @param aabb returns the axis aligned box. // /// @param xf the world transform of the shape. // virtual void ComputeAABB(b2AABB* aabb, const b2Transform& xf) const = 0; // // /// Compute the mass properties of this shape using its dimensions and density. // /// The inertia tensor is computed about the local origin. // /// @param massData returns the mass data for this shape. // /// @param density the density in kilograms per meter squared. // virtual void ComputeMass(b2MassData* massData, float32 density) const = 0; }