com.annahid.libs.artenus.physics

PhysicalBody

Represents a physical body in physics simulation. As the physical body represented by this entity moves and rotates due to physical simulation, this entity will modify the position and rotation of the underlying Entity, depending on connection preferences.

public class PhysicalBody
extends FilteredEntity

Field Summary

Modifier and Type	Field and Description
`public static final`	`POSITION` Defines position connection.
`public static final`	`ROTATION` Defines rotation connection.

Fields inherited from com.annahid.libs.artenus.entities.FilteredEntity

target

Constructor Summary

Modifier and Type	Constructor and Description
`public`	PhysicalBody(Entity entity)
`public`	PhysicalBody(Entity target, Shape shapeDesc) Constructs a PhysicalBody with a given shape.

Method Summary

Modifier and Type	Method and Description
`public final void`	add(JointDescriptor joint) Adds a joint descriptor to this PhysicalBody.
`public void`	advance(float elapsedTime) Updates this physical body to its new state provided by the physics simulator.
`public final void`	applyForce(Point2D force) Applies a 2-dimensional force to the PhysicalBody.
`public final void`	applyForce(Point2D force, Point2D center) Applies a 2-dimensional force to the PhysicalBody.
`public final void`	applyLinearImpulse(Point2D impulse) Applies a 2-dimensional impulse to the PhysicalBody.
`public void`	applyLinearImpulse(Point2D impulse, Point2D center) Applies a 2-dimensional impulse to the PhysicalBody.
`public float`	getAngularDamping() Gets angular damping for the body.
`public final float`	getAngularVelocity() Sets the angular velocity of the body.
`public int`	getConnections() Gets the current connections associated with this physical body.
`public float`	getDensity() Gets the currently assigned density of the body.
`public float`	getFriction() Gets the currently assigned friction of the body.
`public float`	getLinearDamping() Gets linear damping for the body.
`public final Point2D`	getLinearVelocity() Gets the linear velocity of the body.
`public final float`	getMass() Gets the mass of the PhysicalBody in kilograms.
`public final Point2D`	getPosition() Gets the current position of the body.
`public float`	getRestitution() Gets the currently assigned restitution of the body.
`public final float`	getRotation() Gets the rotational angle of the body.
`public final PhysicalBody.Behavior`	getType() Gets the simulation type of this PhysicalBody.
`public final boolean`	isActive() Indicates whether the body is active in simulation and is considered in collision detection.
`public boolean`	isBullet() This method indicated whether the body is a bullet.
`public boolean`	isFixedRotation() Gets whether the rotational angle of the body is fixed in simulation.
`public void`	onAttach(Scene scene) Called when this entity is associated with a scene.
`public void`	onDetach(Scene scene) Called when this entity is dissociated with a scene.
`public final void`	setActive(boolean active) Modifies the active state of the body kin simulation.
`public final void`	setAngularDamping(float damping) Sets angular for the body.
`public final void`	setAngularVelocity(float velocity) Sets the angular velocity of the body.
`public void`	setBullet(boolean bullet) Sets whether the body is a bullet.
`public void`	setConnections(int conn) Sets connections for this physical body.
`public void`	setDensity(float value) Sets the density of the body.
`public void`	setFixedRotation(boolean flag) Sets whether the rotational angle of the body is fixed in simulation.
`public void`	setFriction(float value) Sets the friction of the body.
`public final void`	setLinearDamping(float damping) Sets linear damping for the body.
`public final void`	setLinearVelocity(Point2D velocity) Sets the current linear velocity of the object.
`public final void`	setLinearVelocity(float vx, float vy) Sets the current linear velocity of the object.
`public void`	setPosition(float x, float y) Modifies the position of the body.
`public void`	setRestitution(float value) Sets the restitution of the body.
`public final void`	setRotation(float rotation) Sets the rotation angle of the body.
`public final void`	setShape(Shape s) Sets the Shape of this body.
`public final void`	setType(PhysicalBody.Behavior type) Sets the simulation type of the physical body.

Methods inherited from com.annahid.libs.artenus.entities.FilteredEntity

advance, equals, getAlpha, getAnimation, getColorFilter, getPosition, getRotation, getScale, getUnderlyingEntity, hasBehavior, move, onAttach, onDetach, render, rotate, setAlpha, setAnimation, setColorFilter, setColorFilter, setPosition, setPosition, setRotation, setScale, setScale

Methods inherited from java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

POSITION
public static final POSITION Defines position connection. If this connection is set, the PhysicalBody will lock the position of the underlying entity to that of itself. This connection is set by default for every PhysicalBody.

ROTATION
public static final ROTATION Defines rotation connection. If this connection is set, the PhysicalBody will lock the rotational angle of the underlying entity to that of itself. This connection is set by default for every PhysicalBody.

Constructor Detail

PhysicalBody
public PhysicalBody( Entity entity )

PhysicalBody

public  PhysicalBody(
    Entity target,
    Shape shapeDesc
)

Constructs a PhysicalBody with a given shape.

Parameters:

target	The entity to attach to this physical body
shapeDesc	The initial Shape specification of the body

Method Detail

add

public final void add(
    JointDescriptor joint
)

Adds a joint descriptor to this PhysicalBody. For joints to be effective, they should be added to both bodies involved.

Parameters:

joint

The joint to be added

advance

public void advance(
    float elapsedTime
)

Updates this physical body to its new state provided by the physics simulator. The underlying entity may also be modified, depending on selected connections.

Parameters:

elapsedTime

Elapsed time in seconds since the last frame

Overrides:

advance in FilteredEntity

See Also:

setConnections(int)

applyForce

public final void applyForce(
    Point2D force
)

Applies a 2-dimensional force to the PhysicalBody.

Parameters:

force

The force given in the SI unit

applyForce

public final void applyForce(
    Point2D force,
    Point2D center
)

Applies a 2-dimensional force to the PhysicalBody.

Parameters:

force	The force given in the SI unit
center	The effective point of the force on the PhysicalBody

applyLinearImpulse

public final void applyLinearImpulse(
    Point2D impulse
)

Applies a 2-dimensional impulse to the PhysicalBody.

Parameters:

impulse

The impulse to be applied in SI unit

applyLinearImpulse

public void applyLinearImpulse(
    Point2D impulse,
    Point2D center
)

Applies a 2-dimensional impulse to the PhysicalBody.

Parameters:

impulse	The impulse to be applied in SI unit
center	The effective point of the impulse on the PhysicalBody

getAngularDamping
public float getAngularDamping() Gets angular damping for the body. Returns: The body's angular damping

getAngularVelocity
public final float getAngularVelocity() Sets the angular velocity of the body. Returns: The current angular velocity

getConnections
public int getConnections() Gets the current connections associated with this physical body. Returns: the bit-masked list of connections

getDensity
public float getDensity() Gets the currently assigned density of the body. Returns: Density of the body

getFriction
public float getFriction() Gets the currently assigned friction of the body. Returns: Friction of the body

getLinearDamping
public float getLinearDamping() Gets linear damping for the body. Returns: The body's linear damping

getLinearVelocity
public final Point2D getLinearVelocity() Gets the linear velocity of the body. Returns: The current linear velocity

getMass
public final float getMass() Gets the mass of the PhysicalBody in kilograms. Returns: The mass of the body

getPosition
public final Point2D getPosition() Gets the current position of the body. This position changes with simulation. If the parent game object is added to the scene, this method runs slower than it would when isolated. Overrides: getPosition in FilteredEntity

getRestitution
public float getRestitution() Gets the currently assigned restitution of the body. Restitution determines how much energy the object loses when bouncing. Returns: Restitution of the body

getRotation
public final float getRotation() Gets the rotational angle of the body. Overrides: getRotation in FilteredEntity

getType
public final PhysicalBody.Behavior getType() Gets the simulation type of this PhysicalBody. This type can be one of `DYNAMIC`, `STATIC`, or `KINEMATIC`. Returns: The body type See Also: `PhysicalBody.Behavior`

isActive
public final boolean isActive() Indicates whether the body is active in simulation and is considered in collision detection. Returns: A value indicating whether the body is active

isBullet
public boolean isBullet() This method indicated whether the body is a bullet. A bullet is a fast-moving physical body. Returns: A value indicating whether the body is a bullet

isFixedRotation
public boolean isFixedRotation() Gets whether the rotational angle of the body is fixed in simulation. Returns: A value indicating whether the body's rotation angle should remain fixed

onAttach
public void onAttach( Scene scene ) Called when this entity is associated with a scene. Overrides: onAttach in FilteredEntity

onDetach
public void onDetach( Scene scene ) Called when this entity is dissociated with a scene. Overrides: onDetach in FilteredEntity

setActive

public final void setActive(
    boolean active
)

Modifies the active state of the body kin simulation. If the body is not active, it is not accounted for in collision detection and physics simulation.

Parameters:

active

A value indicating whether the body should be active

setAngularDamping

public final void setAngularDamping(
    float damping
)

Sets angular for the body.

Parameters:

damping

The new angular damping

setAngularVelocity

public final void setAngularVelocity(
    float velocity
)

Sets the angular velocity of the body. If the object is active in simulation, its current angular velocity will be replaced with the new value.

Parameters:

velocity

The new angular velocity

setBullet

public void setBullet(
    boolean bullet
)

Sets whether the body is a bullet. A bullet is a fast-moving physical body. If you have an object that has this characteristic in your game, you should set this flag for better collision processing.

Parameters:

bullet

A new value indicating whether the body is a bullet

setConnections

public void setConnections(
    int conn
)

Sets connections for this physical body. Valid values are POSITION and ROTATION.

Parameters:

conn	the bit-masked list of connections

setDensity

public void setDensity(
    float value
)

Sets the density of the body. Density is accounted for whenever you assign a shape to the body. Changing this value has no effect if the parent game object is already added to the scene. But if you change the shape, the value is applied to the new shape.

Parameters:

value

The new value for density

setFixedRotation

public void setFixedRotation(
    boolean flag
)

Sets whether the rotational angle of the body is fixed in simulation.

Parameters:

flag	A value indicating whether the body's rotation angle should remain fixed

setFriction

public void setFriction(
    float value
)

Sets the friction of the body. Friction is accounted for whenever you assign a shape to the body. Changing this value has no effect if the parent game object is already added to the scene. But if you change the shape, the value is applied to the new shape.

Parameters:

value

The new value for friction

setLinearDamping

public final void setLinearDamping(
    float damping
)

Sets linear damping for the body.

Parameters:

damping

The new linear damping

setLinearVelocity

public final void setLinearVelocity(
    Point2D velocity
)

Sets the current linear velocity of the object. If the object is active in simulation, its current linear velocity is replaced with the new value.

Parameters:

velocity

The new linear velocity

setLinearVelocity

public final void setLinearVelocity(
    float vx,
    float vy
)

Sets the current linear velocity of the object. If the object is active in simulation, its current linear velocity is replaced with the new value.

Parameters:

vx	The x component of the new linear velocity
vy	The y component of the new linear velocity

setPosition

public void setPosition(
    float x,
    float y
)

Modifies the position of the body. The values are given in pixels, but internally stored in metric format.

Parameters:

x	The x component of the new position in pixels
y	The y component of the new position in pixels

Overrides:

setPosition in FilteredEntity

setRestitution

public void setRestitution(
    float value
)

Sets the restitution of the body. Friction is accounted for whenever you assign a shape to the body. Changing this value has no effect if the parent game object is already added to the scene. But if you change the shape, the value is applied to the new shape.

Parameters:

value

The new value for restitution. Setting this value to 1 ensures that the object will not lose any energy when bouncing.

setRotation

public final void setRotation(
    float rotation
)

Sets the rotation angle of the body. This value is internally stored in Radians, but the method takes it in degrees to be compatible with game object attachments.

Parameters:

rotation

The new rotational angle of the body in degrees

Overrides:

setRotation in FilteredEntity

setShape

public final void setShape(
    Shape s
)

Sets the Shape of this body. If the body is already attached to a scene, The shape will change will take effect on the next frame.

Parameters:

s	The new shape for the body