1cfd74d65d832137e20e193c960802afba73b5d38sm/* 23c1e67e433728684b5f228c5d4f3e5b1457bb271sm * Copyright (C) 2010 The Android Open Source Project 3cfd74d65d832137e20e193c960802afba73b5d38sm * 4cfd74d65d832137e20e193c960802afba73b5d38sm * Licensed under the Apache License, Version 2.0 (the "License"); 5cfd74d65d832137e20e193c960802afba73b5d38sm * you may not use this file except in compliance with the License. 6cfd74d65d832137e20e193c960802afba73b5d38sm * You may obtain a copy of the License at 7cfd74d65d832137e20e193c960802afba73b5d38sm * 8cfd74d65d832137e20e193c960802afba73b5d38sm * http://www.apache.org/licenses/LICENSE-2.0 9cfd74d65d832137e20e193c960802afba73b5d38sm * 10cfd74d65d832137e20e193c960802afba73b5d38sm * Unless required by applicable law or agreed to in writing, software 11cfd74d65d832137e20e193c960802afba73b5d38sm * distributed under the License is distributed on an "AS IS" BASIS, 12cfd74d65d832137e20e193c960802afba73b5d38sm * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13cfd74d65d832137e20e193c960802afba73b5d38sm * See the License for the specific language governing permissions and 14cfd74d65d832137e20e193c960802afba73b5d38sm * limitations under the License. 15cfd74d65d832137e20e193c960802afba73b5d38sm */ 16cfd74d65d832137e20e193c960802afba73b5d38sm 17cfd74d65d832137e20e193c960802afba73b5d38smpackage com.replica.replicaisland; 18cfd74d65d832137e20e193c960802afba73b5d38sm 19cfd74d65d832137e20e193c960802afba73b5d38sm 20cfd74d65d832137e20e193c960802afba73b5d38smpublic class OrbitalMagnetComponent extends GameComponent { 21cfd74d65d832137e20e193c960802afba73b5d38sm private final static float DEFAULT_STRENGTH = 15.0f; 22cfd74d65d832137e20e193c960802afba73b5d38sm 23cfd74d65d832137e20e193c960802afba73b5d38sm private float mStrength; 24cfd74d65d832137e20e193c960802afba73b5d38sm private Vector2 mCenter; 25cfd74d65d832137e20e193c960802afba73b5d38sm private Vector2 mDelta; 26cfd74d65d832137e20e193c960802afba73b5d38sm private Vector2 mRim; 27cfd74d65d832137e20e193c960802afba73b5d38sm private Vector2 mVelocity; 28cfd74d65d832137e20e193c960802afba73b5d38sm private float mMagnetRadius; 29cfd74d65d832137e20e193c960802afba73b5d38sm private float mAreaRadius; 30cfd74d65d832137e20e193c960802afba73b5d38sm 31cfd74d65d832137e20e193c960802afba73b5d38sm public OrbitalMagnetComponent() { 32cfd74d65d832137e20e193c960802afba73b5d38sm super(); 33cfd74d65d832137e20e193c960802afba73b5d38sm mCenter = new Vector2(); 34cfd74d65d832137e20e193c960802afba73b5d38sm mDelta = new Vector2(); 35cfd74d65d832137e20e193c960802afba73b5d38sm mRim = new Vector2(); 36cfd74d65d832137e20e193c960802afba73b5d38sm mVelocity = new Vector2(); 37cfd74d65d832137e20e193c960802afba73b5d38sm reset(); 38cfd74d65d832137e20e193c960802afba73b5d38sm setPhase(ComponentPhases.COLLISION_DETECTION.ordinal()); 39cfd74d65d832137e20e193c960802afba73b5d38sm } 40cfd74d65d832137e20e193c960802afba73b5d38sm 41cfd74d65d832137e20e193c960802afba73b5d38sm @Override 42cfd74d65d832137e20e193c960802afba73b5d38sm public void reset() { 43cfd74d65d832137e20e193c960802afba73b5d38sm mCenter.zero(); 44cfd74d65d832137e20e193c960802afba73b5d38sm mDelta.zero(); 45cfd74d65d832137e20e193c960802afba73b5d38sm mRim.zero(); 46cfd74d65d832137e20e193c960802afba73b5d38sm mVelocity.zero(); 47cfd74d65d832137e20e193c960802afba73b5d38sm mStrength = DEFAULT_STRENGTH; 48cfd74d65d832137e20e193c960802afba73b5d38sm mAreaRadius = 0.0f; 49cfd74d65d832137e20e193c960802afba73b5d38sm mMagnetRadius = 0.0f; 50cfd74d65d832137e20e193c960802afba73b5d38sm } 51cfd74d65d832137e20e193c960802afba73b5d38sm 52cfd74d65d832137e20e193c960802afba73b5d38sm @Override 53cfd74d65d832137e20e193c960802afba73b5d38sm public void update(float timeDelta, BaseObject parent) { 54cfd74d65d832137e20e193c960802afba73b5d38sm GameObjectManager manager = sSystemRegistry.gameObjectManager; 55cfd74d65d832137e20e193c960802afba73b5d38sm if (manager != null) { 56cfd74d65d832137e20e193c960802afba73b5d38sm GameObject player = manager.getPlayer(); 57cfd74d65d832137e20e193c960802afba73b5d38sm if (player != null) { 58cfd74d65d832137e20e193c960802afba73b5d38sm GameObject parentObject = (GameObject)parent; 59cfd74d65d832137e20e193c960802afba73b5d38sm applyMagnetism(player, 60cfd74d65d832137e20e193c960802afba73b5d38sm parentObject.getCenteredPositionX(), 61cfd74d65d832137e20e193c960802afba73b5d38sm parentObject.getCenteredPositionY(), 62cfd74d65d832137e20e193c960802afba73b5d38sm timeDelta); 63cfd74d65d832137e20e193c960802afba73b5d38sm } 64cfd74d65d832137e20e193c960802afba73b5d38sm } 65cfd74d65d832137e20e193c960802afba73b5d38sm } 66cfd74d65d832137e20e193c960802afba73b5d38sm 67cfd74d65d832137e20e193c960802afba73b5d38sm private void applyMagnetism(GameObject target, float centerX, float centerY, float timeDelta) { 68cfd74d65d832137e20e193c960802afba73b5d38sm mCenter.set(centerX, centerY); 69cfd74d65d832137e20e193c960802afba73b5d38sm final float targetX = target.getCenteredPositionX(); 70cfd74d65d832137e20e193c960802afba73b5d38sm final float targetY = target.getCenteredPositionY(); 71cfd74d65d832137e20e193c960802afba73b5d38sm mDelta.set(targetX, targetY); 72cfd74d65d832137e20e193c960802afba73b5d38sm mDelta.subtract(mCenter); 73cfd74d65d832137e20e193c960802afba73b5d38sm 74cfd74d65d832137e20e193c960802afba73b5d38sm final float distanceFromCenter2 = mDelta.length2(); 75cfd74d65d832137e20e193c960802afba73b5d38sm final float area2 = mAreaRadius * mAreaRadius; 76cfd74d65d832137e20e193c960802afba73b5d38sm if (distanceFromCenter2 < area2) { 77cfd74d65d832137e20e193c960802afba73b5d38sm mRim.set(mDelta); 78cfd74d65d832137e20e193c960802afba73b5d38sm mRim.normalize(); 79cfd74d65d832137e20e193c960802afba73b5d38sm mRim.multiply(mMagnetRadius); 80cfd74d65d832137e20e193c960802afba73b5d38sm mRim.add(mCenter); 81cfd74d65d832137e20e193c960802afba73b5d38sm // rim is now the closest point on the magnet circle 82cfd74d65d832137e20e193c960802afba73b5d38sm 83cfd74d65d832137e20e193c960802afba73b5d38sm // remove gravity 84cfd74d65d832137e20e193c960802afba73b5d38sm final Vector2 targetVelocity = target.getVelocity(); 85cfd74d65d832137e20e193c960802afba73b5d38sm GravityComponent gravity = target.findByClass(GravityComponent.class); 86cfd74d65d832137e20e193c960802afba73b5d38sm final Vector2 gravityVector = gravity.getGravity(); 87cfd74d65d832137e20e193c960802afba73b5d38sm mVelocity.set(gravityVector); 88cfd74d65d832137e20e193c960802afba73b5d38sm mVelocity.multiply(timeDelta); 89cfd74d65d832137e20e193c960802afba73b5d38sm targetVelocity.subtract(mVelocity); 90cfd74d65d832137e20e193c960802afba73b5d38sm 91cfd74d65d832137e20e193c960802afba73b5d38sm mDelta.add(targetVelocity); 92cfd74d65d832137e20e193c960802afba73b5d38sm mDelta.normalize(); 93cfd74d65d832137e20e193c960802afba73b5d38sm mDelta.multiply(mMagnetRadius); 94cfd74d65d832137e20e193c960802afba73b5d38sm mDelta.add(mCenter); 95cfd74d65d832137e20e193c960802afba73b5d38sm 96cfd74d65d832137e20e193c960802afba73b5d38sm // mDelta is now the next point on the magnet circle in the direction of 97cfd74d65d832137e20e193c960802afba73b5d38sm // movement. 98cfd74d65d832137e20e193c960802afba73b5d38sm 99cfd74d65d832137e20e193c960802afba73b5d38sm mDelta.subtract(mRim); 100cfd74d65d832137e20e193c960802afba73b5d38sm mDelta.normalize(); 101cfd74d65d832137e20e193c960802afba73b5d38sm // Now mDelta is the tangent to the magnet circle, pointing in the direction 102cfd74d65d832137e20e193c960802afba73b5d38sm // of movement. 103cfd74d65d832137e20e193c960802afba73b5d38sm 104cfd74d65d832137e20e193c960802afba73b5d38sm mVelocity.set(mDelta); 105cfd74d65d832137e20e193c960802afba73b5d38sm mVelocity.normalize(); 106cfd74d65d832137e20e193c960802afba73b5d38sm 107cfd74d65d832137e20e193c960802afba73b5d38sm // mVelocity is now the direction to push the player 108cfd74d65d832137e20e193c960802afba73b5d38sm 109cfd74d65d832137e20e193c960802afba73b5d38sm mVelocity.multiply(mStrength); 110cfd74d65d832137e20e193c960802afba73b5d38sm float weight = 1.0f; 111cfd74d65d832137e20e193c960802afba73b5d38sm if (distanceFromCenter2 > mMagnetRadius * mMagnetRadius) { 112cfd74d65d832137e20e193c960802afba73b5d38sm float distance = (float)Math.sqrt(distanceFromCenter2); 113cfd74d65d832137e20e193c960802afba73b5d38sm weight = (distance - mMagnetRadius) / (mAreaRadius - mMagnetRadius); 114cfd74d65d832137e20e193c960802afba73b5d38sm weight = 1.0f - weight; 115cfd74d65d832137e20e193c960802afba73b5d38sm mVelocity.multiply(weight); 116cfd74d65d832137e20e193c960802afba73b5d38sm } 117cfd74d65d832137e20e193c960802afba73b5d38sm final float speed = targetVelocity.length(); 118cfd74d65d832137e20e193c960802afba73b5d38sm targetVelocity.add(mVelocity); 119cfd74d65d832137e20e193c960802afba73b5d38sm if (targetVelocity.length2() > (speed * speed)) { 120cfd74d65d832137e20e193c960802afba73b5d38sm targetVelocity.normalize(); 121cfd74d65d832137e20e193c960802afba73b5d38sm targetVelocity.multiply(speed); 122cfd74d65d832137e20e193c960802afba73b5d38sm } 123cfd74d65d832137e20e193c960802afba73b5d38sm 124cfd74d65d832137e20e193c960802afba73b5d38sm } 125cfd74d65d832137e20e193c960802afba73b5d38sm 126cfd74d65d832137e20e193c960802afba73b5d38sm } 127cfd74d65d832137e20e193c960802afba73b5d38sm 128cfd74d65d832137e20e193c960802afba73b5d38sm public void setup(float areaRadius, float orbitRadius) { 129cfd74d65d832137e20e193c960802afba73b5d38sm mAreaRadius = areaRadius; 130cfd74d65d832137e20e193c960802afba73b5d38sm mMagnetRadius = orbitRadius; 131cfd74d65d832137e20e193c960802afba73b5d38sm } 132cfd74d65d832137e20e193c960802afba73b5d38sm} 133