rigidbody: Add motor constraint

It's implemented as a separate constraint instead of adding properties
to the existing constraints.
Motors only apply linear and angular impulses and don't limit the
movement of rigid bodies, so it's best to use them in conjunction with
other constraints to limit the degrees of freedom.

Thanks to Markus Kasten (markus111) for the initial patch.

1 files changed, 12 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/rigidbody.c b/source/blender/blenkernel/intern/rigidbody.c
index c2fd6a9f54a..4c6bae122cd 100644
--- a/source/blender/blenkernel/intern/rigidbody.c
+++ b/source/blender/blenkernel/intern/rigidbody.c
@@ -633,6 +633,13 @@ void BKE_rigidbody_validate_sim_constraint(RigidBodyWorld *rbw, Object *ob, shor
 					else
 						RB_constraint_set_limits_6dof(rbc->physics_constraint, RB_LIMIT_ANG_Z, 0.0f, -1.0f);
 					break;
+				case RBC_TYPE_MOTOR:
+				    rbc->physics_constraint = RB_constraint_new_motor(loc, rot, rb1, rb2);
+
+				    RB_constraint_set_enable_motor(rbc->physics_constraint, rbc->flag & RBC_FLAG_USE_MOTOR_LIN, rbc->flag & RBC_FLAG_USE_MOTOR_ANG);
+					RB_constraint_set_max_impulse_motor(rbc->physics_constraint, rbc->motor_lin_max_impulse, rbc->motor_ang_max_impulse);
+					RB_constraint_set_target_velocity_motor(rbc->physics_constraint, rbc->motor_lin_target_velocity, rbc->motor_ang_target_velocity);
+				    break;
 			}
 		}
 		else { /* can't create constraint without both rigid bodies */
@@ -816,6 +823,11 @@ RigidBodyCon *BKE_rigidbody_create_constraint(Scene *scene, Object *ob, short ty
 	rbc->spring_stiffness_y = 10.0f;
 	rbc->spring_stiffness_z = 10.0f;
 
+	rbc->motor_lin_max_impulse = 1.0f;
+	rbc->motor_lin_target_velocity = 1.0f;
+	rbc->motor_ang_max_impulse = 1.0f;
+	rbc->motor_ang_target_velocity = 1.0f;
+
 	/* flag cache as outdated */
 	BKE_rigidbody_cache_reset(rbw);