flutter/packages/flutter_sprites/lib/physics_body.dart

361 lines
8.4 KiB
Dart

part of skysprites;
enum PhysicsBodyType {
static,
dynamic
}
class PhysicsBody {
PhysicsBody(this.shape, {
this.tag: null,
this.type: PhysicsBodyType.dynamic,
double density: 1.0,
double friction: 0.0,
double restitution: 0.0,
bool isSensor: false,
Offset linearVelocity: Offset.zero,
double angularVelocity: 0.0,
this.linearDampening: 0.0,
double awakeangularDampening: 0.0,
bool allowSleep: true,
bool awake: true,
bool fixedRotation: false,
bool bullet: false,
bool active: true,
this.gravityScale: 1.0
}) {
this.density = density;
this.friction = friction;
this.restitution = restitution;
this.isSensor = isSensor;
this.linearVelocity = linearVelocity;
this.angularVelocity = angularVelocity;
this.angularDampening = angularDampening;
this.allowSleep = allowSleep;
this.awake = awake;
this.fixedRotation = fixedRotation;
this.bullet = bullet;
this.active = active;
}
Object tag;
final PhysicsShape shape;
PhysicsBodyType type;
double _density;
double get density => _density;
set density(double density) {
_density = density;
if (_body == null)
return;
for (box2d.Fixture f = _body.getFixtureList(); f != null; f = f.getNext()) {
f.setDensity(density);
}
}
double _friction;
double get friction => _friction;
set friction(double friction) {
_friction = friction;
if (_body == null)
return;
for (box2d.Fixture f = _body.getFixtureList(); f != null; f = f.getNext()) {
f.setFriction(friction);
}
}
double _restitution;
double get restitution => _restitution;
set restitution(double restitution) {
_restitution = restitution;
if (_body == null)
return;
for (box2d.Fixture f = _body.getFixtureList(); f != null; f = f.getNext()) {
f.setRestitution(restitution);
}
}
bool _isSensor;
bool get isSensor => _isSensor;
set isSensor(bool isSensor) {
_isSensor = isSensor;
if (_body == null)
return;
for (box2d.Fixture f = _body.getFixtureList(); f != null; f = f.getNext()) {
f.setSensor(isSensor);
}
}
Offset _linearVelocity;
Offset get linearVelocity {
if (_body == null)
return _linearVelocity;
else {
double dx = _body.linearVelocity.x * _physicsNode.b2WorldToNodeConversionFactor;
double dy = _body.linearVelocity.y * _physicsNode.b2WorldToNodeConversionFactor;
return new Offset(dx, dy);
}
}
set linearVelocity(Offset linearVelocity) {
_linearVelocity = linearVelocity;
if (_body != null) {
Vector2 vec = new Vector2(
linearVelocity.dx / _physicsNode.b2WorldToNodeConversionFactor,
linearVelocity.dy / _physicsNode.b2WorldToNodeConversionFactor
);
_body.linearVelocity = vec;
}
}
double _angularVelocity;
double get angularVelocity {
if (_body == null)
return _angularVelocity;
else
return _body.angularVelocity;
}
set angularVelocity(double angularVelocity) {
_angularVelocity = angularVelocity;
if (_body != null) {
_body.angularVelocity = angularVelocity;
}
}
// TODO: Should this be editable in box2d.Body ?
final double linearDampening;
double _angularDampening;
double get angularDampening => _angularDampening;
set angularDampening(double angularDampening) {
_angularDampening = angularDampening;
if (_body != null)
_body.angularDamping = angularDampening;
}
bool _allowSleep;
bool get allowSleep => _allowSleep;
set allowSleep(bool allowSleep) {
_allowSleep = allowSleep;
if (_body != null)
_body.setSleepingAllowed(allowSleep);
}
bool _awake;
bool get awake {
if (_body != null)
return _body.isAwake();
else
return _awake;
}
set awake(bool awake) {
_awake = awake;
if (_body != null)
_body.setAwake(awake);
}
bool _fixedRotation;
bool get fixedRotation => _fixedRotation;
set fixedRotation(bool fixedRotation) {
_fixedRotation = fixedRotation;
if (_body != null)
_body.setFixedRotation(fixedRotation);
}
bool _bullet;
bool get bullet => _bullet;
set bullet(bool bullet) {
_bullet = bullet;
if (_body != null) {
_body.setBullet(bullet);
}
}
bool _active;
bool get active {
if (_body != null)
return _body.isActive();
else
return _active;
}
set active(bool active) {
_active = active;
if (_body != null)
_body.setActive(active);
}
double gravityScale;
PhysicsNode _physicsNode;
Node _node;
box2d.Body _body;
bool _attached = false;
void applyForce(Offset force, Point worldPoint) {
assert(_body != null);
Vector2 b2Force = new Vector2(
force.dx / _physicsNode.b2WorldToNodeConversionFactor,
force.dy / _physicsNode.b2WorldToNodeConversionFactor);
Vector2 b2Point = new Vector2(
worldPoint.x / _physicsNode.b2WorldToNodeConversionFactor,
worldPoint.y / _physicsNode.b2WorldToNodeConversionFactor
);
_body.applyForce(b2Force, b2Point);
}
void applyForceToCenter(Offset force) {
assert(_body != null);
Vector2 b2Force = new Vector2(
force.dx / _physicsNode.b2WorldToNodeConversionFactor,
force.dy / _physicsNode.b2WorldToNodeConversionFactor);
_body.applyForceToCenter(b2Force);
}
void applyTorque(double torque) {
assert(_body != null);
_body.applyTorque(torque / _physicsNode.b2WorldToNodeConversionFactor);
}
void applyLinearImpulse(Offset impulse, Point worldPoint, [bool wake = true]) {
assert(_body != null);
Vector2 b2Impulse = new Vector2(
impulse.dx / _physicsNode.b2WorldToNodeConversionFactor,
impulse.dy / _physicsNode.b2WorldToNodeConversionFactor);
Vector2 b2Point = new Vector2(
worldPoint.x / _physicsNode.b2WorldToNodeConversionFactor,
worldPoint.y / _physicsNode.b2WorldToNodeConversionFactor
);
_body.applyLinearImpulse(b2Impulse, b2Point, wake);
}
void applyAngularImpulse(double impulse) {
assert(_body != null);
_body.applyAngularImpulse(impulse / _physicsNode.b2WorldToNodeConversionFactor);
}
void _attach(PhysicsNode physicsNode, Node node) {
assert(_attached == false);
// Create BodyDef
box2d.BodyDef bodyDef = new box2d.BodyDef();
bodyDef.linearVelocity = new Vector2(linearVelocity.dx, linearVelocity.dy);
bodyDef.angularVelocity = angularVelocity;
bodyDef.linearDamping = linearDampening;
bodyDef.angularDamping = angularDampening;
bodyDef.allowSleep = allowSleep;
bodyDef.awake = awake;
bodyDef.fixedRotation = fixedRotation;
bodyDef.bullet = bullet;
bodyDef.active = active;
bodyDef.gravityScale = gravityScale;
if (type == PhysicsBodyType.dynamic)
bodyDef.type = box2d.BodyType.DYNAMIC;
else
bodyDef.type = box2d.BodyType.STATIC;
double conv = physicsNode.b2WorldToNodeConversionFactor;
bodyDef.position = new Vector2(node.position.x / conv, node.position.y / conv);
bodyDef.angle = radians(node.rotation);
// Create Body
_body = physicsNode.b2World.createBody(bodyDef);
// Create FixtureDef
box2d.FixtureDef fixtureDef = new box2d.FixtureDef();
fixtureDef.friction = friction;
fixtureDef.restitution = restitution;
fixtureDef.density = density;
fixtureDef.isSensor = isSensor;
// Get shapes
List<box2d.Shape> b2Shapes = [];
List<PhysicsShape> physicsShapes = [];
_addB2Shapes(physicsNode, shape, b2Shapes, physicsShapes);
// Create fixtures
for (int i = 0; i < b2Shapes.length; i++) {
box2d.Shape b2Shape = b2Shapes[i];
PhysicsShape physicsShape = physicsShapes[i];
fixtureDef.shape = b2Shape;
box2d.Fixture fixture = _body.createFixtureFromFixtureDef(fixtureDef);
fixture.userData = physicsShape;
}
_body.userData = this;
_physicsNode = physicsNode;
_node = node;
_attached = true;
}
void _detach() {
if (_attached) {
_physicsNode._bodiesScheduledForDestruction.add(_body);
_attached = false;
}
}
void _addB2Shapes(PhysicsNode physicsNode, PhysicsShape shape, List<box2d.Shape> b2Shapes, List<PhysicsShape> physicsShapes) {
if (shape is PhysicsShapeGroup) {
for (PhysicsShape child in shape.shapes) {
_addB2Shapes(physicsNode, child, b2Shapes, physicsShapes);
}
} else {
b2Shapes.add(shape.getB2Shape(physicsNode));
physicsShapes.add(shape);
}
}
}