Changes to 2D physics engine

-=-=-=-=-=-=-=-=-=-=-=-=-=-=

-Removed "density" property
-Added instead more flexible "angular damp" and "linear damp"
-Added ability to override angular and linear damp in rigidbody
-Added gravity scale option rigidbody

Test well and iron out bugs, when it works the same will be moved to 3D

1 files changed, 11 insertions, 3 deletions

diff --git a/servers/physics_2d/body_2d_sw.h b/servers/physics_2d/body_2d_sw.h
index 789fb1cfee..5bd68ba976 100644
--- a/servers/physics_2d/body_2d_sw.h
+++ b/servers/physics_2d/body_2d_sw.h
@@ -47,6 +47,10 @@ class Body2DSW : public CollisionObject2DSW {
 	Vector2 linear_velocity;
 	real_t angular_velocity;
 
+	real_t linear_damp;
+	real_t angular_damp;
+	real_t gravity_scale;
+
 	real_t mass;
 	real_t bounce;
 	real_t friction;
@@ -55,7 +59,8 @@ class Body2DSW : public CollisionObject2DSW {
 	real_t _inv_inertia;
 
 	Vector2 gravity;
-	real_t density;
+	real_t area_linear_damp;
+	real_t area_angular_damp;
 
 	real_t still_time;
 
@@ -219,8 +224,10 @@ public:
 	_FORCE_INLINE_ real_t get_inv_inertia() const { return _inv_inertia; }
 	_FORCE_INLINE_ real_t get_friction() const { return friction; }
 	_FORCE_INLINE_ Vector2 get_gravity() const { return gravity; }
-	_FORCE_INLINE_ real_t get_density() const { return density; }
 	_FORCE_INLINE_ real_t get_bounce() const { return bounce; }
+	_FORCE_INLINE_ real_t get_linear_damp() const { return linear_damp; }
+	_FORCE_INLINE_ real_t get_angular_damp() const { return angular_damp; }
+
 
 	void integrate_forces(real_t p_step);
 	void integrate_velocities(real_t p_step);
@@ -306,7 +313,8 @@ public:
 	real_t step;
 
 	virtual Vector2 get_total_gravity() const {  return body->get_gravity();  } // get gravity vector working on this body space/area
-	virtual float get_total_density() const {  return body->get_density();  } // get density of this body space/area
+	virtual float get_total_angular_damp() const {  return body->get_angular_damp();  } // get density of this body space/area
+	virtual float get_total_linear_damp() const {  return body->get_linear_damp();  } // get density of this body space/area
 
 	virtual float get_inverse_mass() const {  return body->get_inv_mass();  } // get the mass
 	virtual real_t get_inverse_inertia() const { return body->get_inv_inertia();   } // get density of this body space