/*******************************************************************************
* 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;
import java.util.ArrayList;
import com.badlogic.gdx.math.Vector2;
import com.badlogic.gdx.physics.box2d.BodyDef.BodyType;
/**
* A rigid body. These are created via World.CreateBody.
* @author mzechner
*
*/
public class Body {
/** the address of the body **/
protected final long addr;
/** temporary float array **/
private final float[] tmp = new float[4];
/** World **/
private final World world;
/** Fixtures of this body **/
private ArrayList<Fixture> fixtures = new ArrayList<Fixture>(2);
/** Joints of this body **/
protected ArrayList<JointEdge> joints = new ArrayList<JointEdge>(2);
/** user data **/
private Object userData;
/**
* Constructs a new body with the given address
* @param world the world
* @param addr the address
*/
protected Body (World world, long addr) {
this.world = world;
this.addr = addr;
}
/**
* Creates a fixture and attach it to this body. Use this function if you need to set some fixture parameters, like friction.
* Otherwise you can create the fixture directly from a shape. If the density is non-zero, this function automatically updates
* the mass of the body. Contacts are not created until the next time step.
* @param def the fixture definition.
* @warning This function is locked during callbacks.
*/
public Fixture createFixture (FixtureDef def) {
Fixture fixture = new Fixture(this, jniCreateFixture(addr, def.shape.addr, def.friction, def.restitution, def.density,
def.isSensor, def.filter.categoryBits, def.filter.maskBits, def.filter.groupIndex));
this.world.fixtures.put(fixture.addr, fixture);
this.fixtures.add(fixture);
return fixture;
}
private native long jniCreateFixture (long addr, long shapeAddr, float friction, float restitution, float density,
boolean isSensor, short filterCategoryBits, short filterMaskBits, short filterGroupIndex);
/**
* Creates a fixture from a shape and attach it to this body. This is a convenience function. Use b2FixtureDef if you need to
* set parameters like friction, restitution, user data, or filtering. If the density is non-zero, this function automatically
* updates the mass of the body.
* @param shape the shape to be cloned.
* @param density the shape density (set to zero for static bodies).
* @warning This function is locked during callbacks.
*/
public Fixture createFixture (Shape shape, float density) {
Fixture fixture = new Fixture(this, jniCreateFixture(addr, shape.addr, density));
this.world.fixtures.put(fixture.addr, fixture);
this.fixtures.add(fixture);
return fixture;
}
private native long jniCreateFixture (long addr, long shapeAddr, float density);
/**
* Destroy a fixture. This removes the fixture from the broad-phase and destroys all contacts associated with this fixture.
* This will automatically adjust the mass of the body if the body is dynamic and the fixture has positive density. All
* fixtures attached to a body are implicitly destroyed when the body is destroyed.
* @param fixture the fixture to be removed.
* @warning This function is locked during callbacks.
*/
public void destroyFixture (Fixture fixture) {
jniDestroyFixture(addr, fixture.addr);
this.world.fixtures.remove(fixture.addr);
this.fixtures.remove(fixture);
}
private native void jniDestroyFixture (long addr, long fixtureAddr);
/**
* Set the position of the body's origin and rotation. This breaks any contacts and wakes the other bodies. Manipulating a
* body's transform may cause non-physical behavior.
* @param position the world position of the body's local origin.
* @param angle the world rotation in radians.
*/
public void setTransform (Vector2 position, float angle) {
jniSetTransform(addr, position.x, position.y, angle);
}
/**
* Set the position of the body's origin and rotation. This breaks any contacts and wakes the other bodies. Manipulating a
* body's transform may cause non-physical behavior.
* @param x the world position on the x-axis
* @param y the world position on the y-axis
* @param angle the world rotation in radians.
*/
public void setTransform(float x, float y, float angle) {
jniSetTransform(addr, x, y, angle);
}
private native void jniSetTransform (long addr, float positionX, float positionY, float angle);
/**
* Get the body transform for the body's origin. FIXME
*/
private final Transform transform = new Transform();
public Transform getTransform () {
jniGetTransform(addr, transform.vals);
return transform;
}
private native void jniGetTransform (long addr, float[] vals);
private final Vector2 position = new Vector2();
/**
* Get the world body origin position.
* @return the world position of the body's origin.
*/
public Vector2 getPosition () {
jniGetPosition(addr, tmp);
position.x = tmp[0];
position.y = tmp[1];
return position;
}
private native void jniGetPosition (long addr, float[] position);
/**
* Get the angle in radians.
* @return the current world rotation angle in radians.
*/
public float getAngle () {
return jniGetAngle(addr);
}
private native float jniGetAngle (long addr);
/**
* Get the world position of the center of mass.
*/
private final Vector2 worldCenter = new Vector2();
public Vector2 getWorldCenter () {
jniGetWorldCenter(addr, tmp);
worldCenter.x = tmp[0];
worldCenter.y = tmp[1];
return worldCenter;
}
private native void jniGetWorldCenter (long addr, float[] worldCenter);
/**
* Get the local position of the center of mass.
*/
private final Vector2 localCenter = new Vector2();
public Vector2 getLocalCenter () {
jniGetLocalCenter(addr, tmp);
localCenter.x = tmp[0];
localCenter.y = tmp[1];
return localCenter;
}
private native void jniGetLocalCenter (long addr, float[] localCenter);
/**
* Set the linear velocity of the center of mass.
*/
public void setLinearVelocity (Vector2 v) {
jniSetLinearVelocity(addr, v.x, v.y);
}
/**
* Set the linear velocity of the center of mass.
*/
public void setLinearVelocity (float vX, float vY) {
jniSetLinearVelocity(addr, vX, vY);
}
private native void jniSetLinearVelocity (long addr, float x, float y);
/**
* Get the linear velocity of the center of mass.
*/
private final Vector2 linearVelocity = new Vector2();
public Vector2 getLinearVelocity () {
jniGetLinearVelocity(addr, tmp);
linearVelocity.x = tmp[0];
linearVelocity.y = tmp[1];
return linearVelocity;
}
private native void jniGetLinearVelocity (long addr, float[] tmpLinearVelocity);
/**
* Set the angular velocity.
*/
public void setAngularVelocity (float omega) {
jniSetAngularVelocity(addr, omega);
}
private native void jniSetAngularVelocity (long addr, float omega);
/**
* Get the angular velocity.
*/
public float getAngularVelocity () {
return jniGetAngularVelocity(addr);
}
private native float jniGetAngularVelocity (long addr);
/**
* Apply a force at a world point. If the force is not applied at the center of mass, it will generate a torque and affect the
* angular velocity. This wakes up the body.
* @param force the world force vector, usually in Newtons (N).
* @param point the world position of the point of application.
*/
public void applyForce (Vector2 force, Vector2 point) {
jniApplyForce(addr, force.x, force.y, point.x, point.y);
}
/**
* Apply a force at a world point. If the force is not applied at the center of mass, it will generate a torque and affect the
* angular velocity. This wakes up the body.
* @param forceX the world force vector on x, usually in Newtons (N).
* @param forceY the world force vector on y, usually in Newtons (N).
* @param pointX the world position of the point of application on x.
* @param pointY the world position of the point of application on y.
*/
public void applyForce (float forceX, float forceY, float pointX, float pointY) {
jniApplyForce(addr, forceX, forceY, pointX, pointY);
}
private native void jniApplyForce (long addr, float forceX, float forceY, float pointX, float pointY);
/**
* Apply a torque. This affects the angular velocity without affecting the linear velocity of the center of mass. This wakes up
* the body.
* @param torque about the z-axis (out of the screen), usually in N-m.
*/
public void applyTorque (float torque) {
jniApplyTorque(addr, torque);
}
private native void jniApplyTorque (long addr, float torque);
/**
* Apply an impulse at a point. This immediately modifies the velocity. It also modifies the angular velocity if the point of
* application is not at the center of mass. This wakes up the body.
* @param impulse the world impulse vector, usually in N-seconds or kg-m/s.
* @param point the world position of the point of application.
*/
public void applyLinearImpulse (Vector2 impulse, Vector2 point) {
jniApplyLinearImpulse(addr, impulse.x, impulse.y, point.x, point.y);
}
/**
* Apply an impulse at a point. This immediately modifies the velocity. It also modifies the angular velocity if the point of
* application is not at the center of mass. This wakes up the body.
* @param impulseX the world impulse vector on the x-axis, usually in N-seconds or kg-m/s.
* @param impulseY the world impulse vector on the y-axis, usually in N-seconds or kg-m/s.
* @param pointX the world position of the point of application on the x-axis.
* @param pointY the world position of the point of application on the y-axis.
*/
public void applyLinearImpulse(float impulseX, float impulseY, float pointX, float pointY) {
jniApplyLinearImpulse(addr, impulseX, impulseY, pointX, pointY);
}
private native void jniApplyLinearImpulse (long addr, float impulseX, float impulseY, float pointX, float pointY);
/**
* Apply an angular impulse.
* @param impulse the angular impulse in units of kg*m*m/s
*/
public void applyAngularImpulse (float impulse) {
jniApplyAngularImpulse(addr, impulse);
}
private native void jniApplyAngularImpulse (long addr, float impulse);
/**
* Get the total mass of the body.
* @return the mass, usually in kilograms (kg).
*/
public float getMass () {
return jniGetMass(addr);
}
private native float jniGetMass (long addr);
/**
* Get the rotational inertia of the body about the local origin.
* @return the rotational inertia, usually in kg-m^2.
*/
public float getInertia () {
return jniGetInertia(addr);
}
private native float jniGetInertia (long addr);
private final MassData massData = new MassData();
/**
* Get the mass data of the body.
* @return a struct containing the mass, inertia and center of the body.
*/
public MassData getMassData () {
jniGetMassData(addr, tmp);
massData.mass = tmp[0];
massData.center.x = tmp[1];
massData.center.y = tmp[2];
massData.I = tmp[3];
return massData;
}
private native void jniGetMassData (long addr, float[] massData);
/**
* Set the mass properties to override the mass properties of the fixtures. Note that this changes the center of mass position.
* Note that creating or destroying fixtures can also alter the mass. This function has no effect if the body isn't dynamic.
* @param data the mass properties.
*/
public void setMassData (MassData data) {
jniSetMassData(addr, data.mass, data.center.x, data.center.y, data.I);
}
private native void jniSetMassData (long addr, float mass, float centerX, float centerY, float I);
/**
* This resets the mass properties to the sum of the mass properties of the fixtures. This normally does not need to be called
* unless you called SetMassData to override the mass and you later want to reset the mass.
*/
public void resetMassData () {
jniResetMassData(addr);
}
private native void jniResetMassData (long addr);
private final Vector2 localPoint = new Vector2();
/**
* Get the world coordinates of a point given the local coordinates.
* @param localPoint a point on the body measured relative the the body's origin.
* @return the same point expressed in world coordinates.
*/
public Vector2 getWorldPoint (Vector2 localPoint) {
jniGetWorldPoint(addr, localPoint.x, localPoint.y, tmp);
this.localPoint.x = tmp[0];
this.localPoint.y = tmp[1];
return this.localPoint;
}
private native void jniGetWorldPoint (long addr, float localPointX, float localPointY, float[] worldPoint);
private final Vector2 worldVector = new Vector2();
/**
* Get the world coordinates of a vector given the local coordinates.
* @param localVector a vector fixed in the body.
* @return the same vector expressed in world coordinates.
*/
public Vector2 getWorldVector (Vector2 localVector) {
jniGetWorldVector(addr, localVector.x, localVector.y, tmp);
worldVector.x = tmp[0];
worldVector.y = tmp[1];
return worldVector;
}
private native void jniGetWorldVector (long addr, float localVectorX, float localVectorY, float[] worldVector);
public final Vector2 localPoint2 = new Vector2();
/**
* Gets a local point relative to the body's origin given a world point.
* @param worldPoint a point in world coordinates.
* @return the corresponding local point relative to the body's origin.
*/
public Vector2 getLocalPoint (Vector2 worldPoint) {
jniGetLocalPoint(addr, worldPoint.x, worldPoint.y, tmp);
localPoint2.x = tmp[0];
localPoint2.y = tmp[1];
return localPoint2;
}
private native void jniGetLocalPoint (long addr, float worldPointX, float worldPointY, float[] localPoint);
public final Vector2 localVector = new Vector2();
/**
* Gets a local vector given a world vector.
* @param worldVector a vector in world coordinates.
* @return the corresponding local vector.
*/
public Vector2 getLocalVector (Vector2 worldVector) {
jniGetLocalVector(addr, worldVector.x, worldVector.y, tmp);
localVector.x = tmp[0];
localVector.y = tmp[1];
return localVector;
}
private native void jniGetLocalVector (long addr, float worldVectorX, float worldVectorY, float[] worldVector);
public final Vector2 linVelWorld = new Vector2();
/**
* Get the world linear velocity of a world point attached to this body.
* @param worldPoint a point in world coordinates.
* @return the world velocity of a point.
*/
public Vector2 getLinearVelocityFromWorldPoint (Vector2 worldPoint) {
jniGetLinearVelocityFromWorldPoint(addr, worldPoint.x, worldPoint.y, tmp);
linVelWorld.x = tmp[0];
linVelWorld.y = tmp[1];
return linVelWorld;
}
private native void jniGetLinearVelocityFromWorldPoint (long addr, float worldPointX, float worldPointY, float[] linVelWorld);
public final Vector2 linVelLoc = new Vector2();
/**
* Get the world velocity of a local point.
* @param localPoint a point in local coordinates.
* @return the world velocity of a point.
*/
public Vector2 getLinearVelocityFromLocalPoint (Vector2 localPoint) {
jniGetLinearVelocityFromLocalPoint(addr, localPoint.x, localPoint.y, tmp);
linVelLoc.x = tmp[0];
linVelLoc.y = tmp[1];
return linVelLoc;
}
private native void jniGetLinearVelocityFromLocalPoint (long addr, float localPointX, float localPointY, float[] linVelLoc);
/**
* Get the linear damping of the body.
*/
public float getLinearDamping () {
return jniGetLinearDamping(addr);
}
private native float jniGetLinearDamping (long add);
/**
* Set the linear damping of the body.
*/
public void setLinearDamping (float linearDamping) {
jniSetLinearDamping(addr, linearDamping);
}
private native void jniSetLinearDamping (long addr, float linearDamping);
/**
* Get the angular damping of the body.
*/
public float getAngularDamping () {
return jniGetAngularDamping(addr);
}
private native float jniGetAngularDamping (long addr);
/**
* Set the angular damping of the body.
*/
public void setAngularDamping (float angularDamping) {
jniSetAngularDamping(addr, angularDamping);
}
private native void jniSetAngularDamping (long addr, float angularDamping);
/**
* Set the type of this body. This may alter the mass and velocity.
*/
public void setType (BodyType type) {
jniSetType(addr, type.getValue());
}
private native void jniSetType (long addr, int type);
/**
* Get the type of this body.
*/
public BodyType getType () {
int type = jniGetType(addr);
if (type == 0) return BodyType.StaticBody;
if (type == 1) return BodyType.KinematicBody;
if (type == 2) return BodyType.DynamicBody;
return BodyType.StaticBody;
}
private native int jniGetType (long addr);
/**
* Should this body be treated like a bullet for continuous collision detection?
*/
public void setBullet (boolean flag) {
jniSetBullet(addr, flag);
}
private native void jniSetBullet (long addr, boolean flag);
/**
* Is this body treated like a bullet for continuous collision detection?
*/
public boolean isBullet () {
return jniIsBullet(addr);
}
private native boolean jniIsBullet (long addr);
/**
* You can disable sleeping on this body. If you disable sleeping, the
*/
public void setSleepingAllowed (boolean flag) {
jniSetSleepingAllowed(addr, flag);
}
private native void jniSetSleepingAllowed (long addr, boolean flag);
/**
* Is this body allowed to sleep
*/
public boolean isSleepingAllowed () {
return jniIsSleepingAllowed(addr);
}
private native boolean jniIsSleepingAllowed (long addr);
/**
* Set the sleep state of the body. A sleeping body has very low CPU cost.
* @param flag set to true to put body to sleep, false to wake it.
*/
public void setAwake (boolean flag) {
jniSetAwake(addr, flag);
}
private native void jniSetAwake (long addr, boolean flag);
/**
* Get the sleeping state of this body.
* @return true if the body is sleeping.
*/
public boolean isAwake () {
return jniIsAwake(addr);
}
private native boolean jniIsAwake (long addr);
/**
* Set the active state of the body. An inactive body is not simulated and cannot be collided with or woken up. If you pass a
* flag of true, all fixtures will be added to the broad-phase. If you pass a flag of false, all fixtures will be removed from
* the broad-phase and all contacts will be destroyed. Fixtures and joints are otherwise unaffected. You may continue to
* create/destroy fixtures and joints on inactive bodies. Fixtures on an inactive body are implicitly inactive and will not
* participate in collisions, ray-casts, or queries. Joints connected to an inactive body are implicitly inactive. An inactive
* body is still owned by a b2World object and remains in the body list.
*/
public void setActive (boolean flag) {
jniSetActive(addr, flag);
}
private native void jniSetActive (long addr, boolean flag);
/**
* Get the active state of the body.
*/
public boolean isActive () {
return jniIsActive(addr);
}
private native boolean jniIsActive (long addr);
/**
* Set this body to have fixed rotation. This causes the mass to be reset.
*/
public void setFixedRotation (boolean flag) {
jniSetFixedRotation(addr, flag);
}
private native void jniSetFixedRotation (long addr, boolean flag);
/**
* Does this body have fixed rotation?
*/
public boolean isFixedRotation () {
return jniIsFixedRotation(addr);
}
private native boolean jniIsFixedRotation (long addr);
/**
* Get the list of all fixtures attached to this body. Do not modify the list!
*/
public ArrayList<Fixture> getFixtureList () {
return fixtures;
}
/**
* Get the list of all joints attached to this body. Do not modify the list!
*/
public ArrayList<JointEdge> getJointList () {
return joints;
}
/**
* Get the list of all contacts attached to this body.
* @warning this list changes during the time step and you may miss some collisions if you don't use b2ContactListener. Do not
* modify the returned list!
*/
// ArrayList<ContactEdge> getContactList()
// {
// return contacts;
// }
/**
* Get the parent world of this body.
*/
public World getWorld () {
return world;
}
/**
* Get the user data
*/
public Object getUserData () {
return userData;
}
/**
* Set the user data
*/
public void setUserData (Object userData) {
this.userData = userData;
}
}