feat!: remove JointType (#45)

packages/forge2d/lib/forge2d.dart

@@ -70,7 +70,6 @@ export 'src/dynamics/joints/gear_joint_def.dart';
 export 'src/dynamics/joints/jacobian.dart';
 export 'src/dynamics/joints/joint.dart';
 export 'src/dynamics/joints/joint_def.dart';
-export 'src/dynamics/joints/joint_type.dart';
 export 'src/dynamics/joints/limit_state.dart';
 export 'src/dynamics/joints/motor_joint.dart';
 export 'src/dynamics/joints/motor_joint_def.dart';

packages/forge2d/lib/src/dynamics/joints/constant_volume_joint_def.dart

@@ -10,10 +10,6 @@ class ConstantVolumeJointDef<A extends Body> extends JointDef<A, A> {
   final List<A> bodies = <A>[];
   final List<DistanceJoint> joints = [];
 
-  ConstantVolumeJointDef() : super(JointType.constantVolume) {
-    collideConnected = false;
-  }
-
   /// Adds a body to the group
   ///
   /// @param argBody

packages/forge2d/lib/src/dynamics/joints/distance_joint_def.dart

@@ -15,8 +15,6 @@ class DistanceJointDef<A extends Body, B extends Body> extends JointDef<A, B> {
   /// The damping ratio. 0 = no damping, 1 = critical damping.
   double dampingRatio = 0.0;
 
-  DistanceJointDef() : super(JointType.distance);
-
   /// Initialize the bodies, anchors, and length using the world anchors.
   ///
   /// @param b1 First body

packages/forge2d/lib/src/dynamics/joints/friction_joint_def.dart

@@ -8,8 +8,6 @@ class FrictionJointDef<A extends Body, B extends Body> extends JointDef<A, B> {
   /// The maximum friction torque in N-m.
   double maxTorque = 0.0;
 
-  FrictionJointDef() : super(JointType.friction);
-
   /// Initialize the bodies, anchors, axis, and reference angle using the world anchor and world
   /// axis.
   void initialize(A bodyA, B bodyB, Vector2 anchor) {

packages/forge2d/lib/src/dynamics/joints/gear_joint.dart

@@ -32,9 +32,6 @@ class GearJoint extends Joint {
   final Joint _joint1;
   final Joint _joint2;
 
-  final JointType _typeA;
-  final JointType _typeB;
-
   // Body A is connected to body C
   // Body B is connected to body D
   final Body _bodyC;
@@ -71,13 +68,14 @@ class GearJoint extends Joint {
   GearJoint(GearJointDef def)
       : _joint1 = def.joint1,
         _joint2 = def.joint2,
-        _typeA = def.joint1.type,
-        _typeB = def.joint2.type,
         _bodyC = def.joint1.bodyA,
         _bodyD = def.joint2.bodyA,
         super(def) {
-    assert(_typeA == JointType.revolute || _typeA == JointType.prismatic);
-    assert(_typeB == JointType.revolute || _typeB == JointType.prismatic);
+    assert(
+      (_joint1 is RevoluteJoint || _joint1 is PrismaticJoint) &&
+          (_joint2 is RevoluteJoint || _joint2 is PrismaticJoint),
+      'A GearJoint can only be joint with RevoluteJoint and/or PrismaticJoint.',
+    );
 
     double coordinateA, coordinateB;
 
@@ -90,7 +88,7 @@ class GearJoint extends Joint {
     final xfC = _bodyC.transform;
     final aC = _bodyC.sweep.a;
 
-    if (_typeA == JointType.revolute) {
+    if (_joint1 is RevoluteJoint) {
       final revolute = def.joint1 as RevoluteJoint;
       _localAnchorC.setFrom(revolute.localAnchorA);
       localAnchorA.setFrom(revolute.localAnchorB);
@@ -124,7 +122,7 @@ class GearJoint extends Joint {
     final xfD = _bodyD.transform;
     final aD = _bodyD.sweep.a;
 
-    if (_typeB == JointType.revolute) {
+    if (_joint2 is RevoluteJoint) {
       final revolute = def.joint2 as RevoluteJoint;
       _localAnchorD.setFrom(revolute.localAnchorA);
       localAnchorB.setFrom(revolute.localAnchorB);
@@ -228,7 +226,7 @@ class GearJoint extends Joint {
 
     final temp = Vector2.zero();
 
-    if (_typeA == JointType.revolute) {
+    if (_joint1 is RevoluteJoint) {
       _jvAC.setZero();
       _jwA = 1.0;
       _jwC = 1.0;
@@ -250,7 +248,7 @@ class GearJoint extends Joint {
       _mass += _mC + _mA + _iC * _jwC * _jwC + _iA * _jwA * _jwA;
     }
 
-    if (_typeB == JointType.revolute) {
+    if (_joint2 is RevoluteJoint) {
       _jvBD.setZero();
       _jwB = _ratio;
       _jwD = _ratio;
@@ -399,7 +397,7 @@ class GearJoint extends Joint {
     double jwA, jwB, jwC, jwD;
     var mass = 0.0;
 
-    if (_typeA == JointType.revolute) {
+    if (_joint1 is RevoluteJoint) {
       jvBC.setZero();
       jwA = 1.0;
       jwC = 1.0;
@@ -435,7 +433,7 @@ class GearJoint extends Joint {
       coordinateA = (pA..sub(pC)).dot(_localAxisC);
     }
 
-    if (_typeB == JointType.revolute) {
+    if (_joint2 is RevoluteJoint) {
       jvBD.setZero();
       jwB = _ratio;
       jwD = _ratio;

packages/forge2d/lib/src/dynamics/joints/gear_joint_def.dart

@@ -13,6 +13,4 @@ class GearJointDef<A extends Body, B extends Body> extends JointDef<A, B> {
   ///
   /// @see GearJoint
   double ratio = 0.0;
-
-  GearJointDef() : super(JointType.gear);
 }

packages/forge2d/lib/src/dynamics/joints/joint.dart

@@ -4,33 +4,33 @@ import '../../../forge2d.dart';
 /// joints also feature limits and motors.
 abstract class Joint {
   static T create<T extends Joint>(World world, JointDef def) {
-    if (T == ConstantVolumeJoint || def.type == JointType.constantVolume) {
+    if (T == ConstantVolumeJoint || def is ConstantVolumeJointDef) {
       return ConstantVolumeJoint(world, def as ConstantVolumeJointDef) as T;
-    } else if (T == DistanceJoint || def.type == JointType.distance) {
+    } else if (T == DistanceJoint || def is DistanceJointDef) {
       return DistanceJoint(def as DistanceJointDef) as T;
-    } else if (T == FrictionJoint || def.type == JointType.friction) {
+    } else if (T == FrictionJoint || def is FrictionJointDef) {
       return FrictionJoint(def as FrictionJointDef) as T;
-    } else if (T == GearJoint || def.type == JointType.gear) {
+    } else if (T == GearJoint || def is GearJointDef) {
       return GearJoint(def as GearJointDef) as T;
-    } else if (T == MotorJoint || def.type == JointType.motor) {
+    } else if (T == MotorJoint || def is MotorJointDef) {
       return MotorJoint(def as MotorJointDef) as T;
-    } else if (T == MouseJoint || def.type == JointType.mouse) {
+    } else if (T == MouseJoint || def is MouseJointDef) {
       return MouseJoint(def as MouseJointDef) as T;
-    } else if (T == PrismaticJoint || def.type == JointType.prismatic) {
+    } else if (T == PrismaticJoint || def is PrismaticJointDef) {
       return PrismaticJoint(def as PrismaticJointDef) as T;
-    } else if (T == PulleyJoint || def.type == JointType.pulley) {
+    } else if (T == PulleyJoint || def is PulleyJointDef) {
       return PulleyJoint(def as PulleyJointDef) as T;
-    } else if (T == RevoluteJoint || def.type == JointType.revolute) {
+    } else if (T == RevoluteJoint || def is RevoluteJointDef) {
       return RevoluteJoint(def as RevoluteJointDef) as T;
-    } else if (T == RopeJoint || def.type == JointType.rope) {
+    } else if (T == RopeJoint || def is RopeJointDef) {
       return RopeJoint(def as RopeJointDef) as T;
-    } else if (T == WeldJoint || def.type == JointType.weld) {
+    } else if (T == WeldJoint || def is WeldJointDef) {
       return WeldJoint(def as WeldJointDef) as T;
-    } else if (T == WheelJoint || def.type == JointType.wheel) {
+    } else if (T == WheelJoint || def is WheelJointDef) {
       return WheelJoint(def as WheelJointDef) as T;
     } else {
       throw ArgumentError(
-        'Invalid joint type $T with invalid joint definition ${def.type}',
+        'Invalid joint type $T with invalid joint definition $def',
       );
     }
   }
@@ -39,7 +39,6 @@ abstract class Joint {
     joint.destructor();
   }
 
-  final JointType _type;
   late Body bodyA;
   late Body bodyB;
 
@@ -52,19 +51,13 @@ abstract class Joint {
   Joint(JointDef def)
       : assert(def.bodyA != def.bodyB),
         localAnchorA = def.localAnchorA,
-        localAnchorB = def.localAnchorB,
-        _type = def.type {
+        localAnchorB = def.localAnchorB {
     bodyA = def.bodyA;
     bodyB = def.bodyB;
     _collideConnected = def.collideConnected;
     islandFlag = false;
   }
 
-  /// get the type of the concrete joint.
-  ///
-  /// @return
-  JointType get type => _type;
-
   /// Whether the body is connected to the joint
   bool containsBody(Body body) => body == bodyA || body == bodyB;
 
@@ -131,34 +124,23 @@ abstract class Joint {
 
     _color.setFromRGBd(0.5, 0.8, 0.8);
 
-    switch (type) {
-      case JointType.distance:
-        debugDraw.drawSegment(p1, p2, _color);
-        break;
-
-      case JointType.pulley:
-        {
-          final pulley = this as PulleyJoint;
-          final s1 = pulley.getGroundAnchorA();
-          final s2 = pulley.getGroundAnchorB();
-          debugDraw.drawSegment(s1, p1, _color);
-          debugDraw.drawSegment(s2, p2, _color);
-          debugDraw.drawSegment(s1, s2, _color);
-        }
-        break;
-
-      case JointType.friction:
-        debugDraw.drawSegment(x1, x2, _color);
-        break;
-
-      case JointType.constantVolume:
-      case JointType.mouse:
-        // don't draw this
-        break;
-      default:
-        debugDraw.drawSegment(x1, p1, _color);
-        debugDraw.drawSegment(p1, p2, _color);
-        debugDraw.drawSegment(x2, p2, _color);
+    if (this is DistanceJoint) {
+      debugDraw.drawSegment(p1, p2, _color);
+    } else if (this is PulleyJoint) {
+      final pulley = this as PulleyJoint;
+      final s1 = pulley.getGroundAnchorA();
+      final s2 = pulley.getGroundAnchorB();
+      debugDraw.drawSegment(s1, p1, _color);
+      debugDraw.drawSegment(s2, p2, _color);
+      debugDraw.drawSegment(s1, s2, _color);
+    } else if (this is FrictionJoint) {
+      debugDraw.drawSegment(x1, x2, _color);
+    } else if (this is ConstantVolumeJoint || this is MouseJoint) {
+      // Don't draw these joints.
+    } else {
+      debugDraw.drawSegment(x1, p1, _color);
+      debugDraw.drawSegment(p1, p2, _color);
+      debugDraw.drawSegment(x2, p2, _color);
     }
   }
 }

packages/forge2d/lib/src/dynamics/joints/joint_def.dart

@@ -4,27 +4,24 @@ import '../../../forge2d.dart';
 /// [JointDef]s are used to construct [Joint]s.
 ///
 /// All [Joint]s are connected between two different [Body]ies.
-/// One [Body] may [BodyType.static].
+/// One [Body] may be [BodyType.static].
 ///
 /// [Joint]s between [BodyType.static] and/or [BodyType.kinematic] are allowed,
 /// but have no effect and use some processing time.
 ///
-/// If possible, avoid directly extending [JointDef]. Instead, extend from an
-/// already defined [JointDef] implementation.
+/// Don't subclass [JointDef]. Instead, extend from an already defined
+/// [JointDef] subclass.
 /// {@endtemplate}
 abstract class JointDef<A extends Body, B extends Body> {
-  /// {@macro dynamics.joints.joint_def.type}
-  JointDef(this.type, [this.collideConnected = false]);
+  /// {@macro dynamics.joints.joint_def}
+  JointDef([this.collideConnected = false]);
 
   /// The local anchor point relative to body1's origin.
   final Vector2 localAnchorA = Vector2.zero();
 
   /// The local anchor point relative to body2's origin.
   final Vector2 localAnchorB = Vector2.zero();
 
-  /// The joint type is set automatically for concrete joint types.
-  JointType type;
-
   /// Use this to attach application specific data to your joints.
   Object? userData;
 

packages/forge2d/lib/src/dynamics/joints/motor_joint_def.dart

@@ -17,8 +17,6 @@ class MotorJointDef<A extends Body, B extends Body> extends JointDef<A, B> {
   /// Position correction factor in the range [0,1].
   double correctionFactor = 0.3;
 
-  MotorJointDef() : super(JointType.motor);
-
   void initialize(A bodyA, B bodyB) {
     this.bodyA = bodyA;
     this.bodyB = bodyB;

packages/forge2d/lib/src/dynamics/joints/mouse_joint_def.dart

@@ -14,6 +14,4 @@ class MouseJointDef<A extends Body, B extends Body> extends JointDef<A, B> {
 
   /// The damping ratio. 0 = no damping, 1 = critical damping.
   double dampingRatio = .7;
-
-  MouseJointDef() : super(JointType.mouse);
 }

packages/forge2d/lib/src/dynamics/joints/prismatic_joint_def.dart

@@ -32,8 +32,6 @@ class PrismaticJointDef<A extends Body, B extends Body> extends JointDef<A, B> {
   /// The desired motor speed in radians per second.
   double motorSpeed = 0.0;
 
-  PrismaticJointDef() : super(JointType.prismatic);
-
   /// Initialize the bodies, anchors, axis, and reference angle using the world anchor and world
   /// axis.
   void initialize(A b1, B b2, Vector2 anchor, Vector2 axis) {

packages/forge2d/lib/src/dynamics/joints/pulley_joint_def.dart

@@ -19,9 +19,7 @@ class PulleyJointDef<A extends Body, B extends Body> extends JointDef<A, B> {
   /// The pulley ratio, used to simulate a block-and-tackle.
   double ratio = 1.0;
 
-  PulleyJointDef() : super(JointType.pulley) {
-    collideConnected = true;
-  }
+  PulleyJointDef() : super(true);
 
   /// Initialize the bodies, anchors, lengths, max lengths, and ratio using the world anchors.
   void initialize(

packages/forge2d/lib/src/dynamics/joints/revolute_joint_def.dart

@@ -31,8 +31,6 @@ class RevoluteJointDef<A extends Body, B extends Body> extends JointDef<A, B> {
   /// The maximum motor torque used to achieve the desired motor speed. Usually in N-m.
   double maxMotorTorque = 0.0;
 
-  RevoluteJointDef() : super(JointType.revolute);
-
   /// Initialize the bodies, anchors, and reference angle using the world anchor.
   ///
   /// @param b1

packages/forge2d/lib/src/dynamics/joints/rope_joint_def.dart

@@ -7,7 +7,7 @@ class RopeJointDef<A extends Body, B extends Body> extends JointDef<A, B> {
   /// will have no effect.
   double maxLength = 0.0;
 
-  RopeJointDef() : super(JointType.rope) {
+  RopeJointDef() : super() {
     localAnchorA.setValues(-1.0, 0.0);
     localAnchorB.setValues(1.0, 0.0);
   }

packages/forge2d/lib/src/dynamics/joints/weld_joint_def.dart

@@ -10,8 +10,6 @@ class WeldJointDef<A extends Body, B extends Body> extends JointDef<A, B> {
   /// The damping ratio. 0 = no damping, 1 = critical damping.
   double dampingRatio = 0.0;
 
-  WeldJointDef() : super(JointType.weld);
-
   /// Initialize the bodies, anchors, and reference angle using a world anchor point.
   void initialize(A bodyA, B bodyB, Vector2 anchor) {
     this.bodyA = bodyA;

packages/forge2d/lib/src/dynamics/joints/wheel_joint_def.dart

@@ -24,7 +24,7 @@ class WheelJointDef<A extends Body, B extends Body> extends JointDef<A, B> {
   /// Suspension damping ratio, one indicates critical damping
   double dampingRatio = 0.0;
 
-  WheelJointDef() : super(JointType.wheel) {
+  WheelJointDef() : super() {
     localAxisA.setValues(1.0, 0.0);
   }
 

packages/forge2d/test/dynamics/joints/constant_volume_joint_def_test.dart

@@ -1,6 +1,5 @@
 import 'package:forge2d/forge2d.dart';
-import 'package:test/expect.dart';
-import 'package:test/scaffolding.dart';
+import 'package:test/test.dart';
 
 void main() {
   group('ConstantVolumeJointDef', () {