Merge pull request #429 from fabriceci/add-methods-retrieves-forces-and-torques

Adds methods to retrieve forces added by the user.

CHANGELOG.md

@@ -9,6 +9,8 @@
   Disabling a multibody joint isn’t supported yet.
 - Add `DynamicRayCastVehicleController`, a vehicle controller based on ray-casting and dynamic rigid-bodies (mostly
   a port of the vehicle controller from Bullet physics).
+- Add `RigidBody::user_force` and `RigidBody::user_torque` to read the forces or torques added by the user to a
+  dynamic rigid-body.
 
 ### Modified
 - Add the `QueryPipeline` as an optional argument to `PhysicsPipeline::step` and `CollisionPipeline::step`. If this

src/dynamics/rigid_body.rs

@@ -938,6 +938,28 @@ impl RigidBody {
         self.apply_impulse(impulse, wake_up);
         self.apply_torque_impulse(torque_impulse, wake_up);
     }
+
+    /// Retrieves the constant force(s) that the user has added to the body.
+    ///
+    /// Returns zero if the rigid-body isn’t dynamic.
+    pub fn user_force(&self) -> Vector<Real> {
+        if self.body_type == RigidBodyType::Dynamic {
+            self.forces.user_force
+        } else {
+            Vector::zeros()
+        }
+    }
+
+    /// Retrieves the constant torque(s) that the user has added to the body.
+    ///
+    /// Returns zero if the rigid-body isn’t dynamic.
+    pub fn user_torque(&self) -> AngVector<Real> {
+        if self.body_type == RigidBodyType::Dynamic {
+            self.forces.user_torque
+        } else {
+            AngVector::zero()
+        }
+    }
 }
 
 impl RigidBody {