Fixed comments regarding joint rotation direction

opsocket · Dec 22, 2023 · bc07d40 · bc07d40
1 parent 41ca5aa
commit bc07d40
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Showing 4 changed files with 5 additions and 11 deletions.
diff --git a/src/joints/jolt_cone_twist_joint_impl_3d.cpp b/src/joints/jolt_cone_twist_joint_impl_3d.cpp
@@ -338,8 +338,7 @@ void JoltConeTwistJointImpl3D::_update_twist_motor_state() {
 
 void JoltConeTwistJointImpl3D::_update_motor_velocity() {
 	if (auto* constraint = static_cast<JPH::SwingTwistConstraint*>(jolt_ref.GetPtr())) {
-		// HACK(mihe): For reasons I don't entirely understand we're forced to flip the directions
-		// of these for it to make sense with the direction of the joint's actual axes.
+		// NOTE(mihe): We flip the direction since Jolt is CCW but Godot is CW.
 		constraint->SetTargetAngularVelocityCS(
 			{(float)-twist_motor_target_speed,
 			 (float)-swing_motor_target_speed_y,

diff --git a/src/joints/jolt_generic_6dof_joint_impl_3d.cpp b/src/joints/jolt_generic_6dof_joint_impl_3d.cpp
@@ -565,7 +565,7 @@ void JoltGeneric6DOFJointImpl3D::_update_motor_velocity(int32_t p_axis) {
 			 (float)motor_speed[AXIS_LINEAR_Z]}
 		);
 	} else {
-		// HACK(mihe): We're forced to flip the direction of these to match Godot Physics.
+		// NOTE(mihe): We flip the direction since Jolt is CCW but Godot is CW.
 		constraint->SetTargetAngularVelocityCS(
 			{(float)-motor_speed[AXIS_ANGULAR_X],
 			 (float)-motor_speed[AXIS_ANGULAR_Y],
@@ -580,9 +580,8 @@ void JoltGeneric6DOFJointImpl3D::_update_motor_limit(int32_t p_axis) {
 
 	JPH::MotorSettings& motor_settings = constraint->GetMotorSettings((JoltAxis)p_axis);
 
-	// HACK(mihe): We only apply the motor limit if we're actually using a velocity motor, since
-	// it would otherwise affect a position motor as well, which doesn't seem to be how this is
-	// applied in the Bullet implementation in Godot 3.
+	// NOTE(mihe): We only apply the motor limit if we're actually using a velocity motor, since it
+	// would otherwise affect a position motor as well.
 	const auto limit = motor_enabled[p_axis] ? (float)motor_limit[p_axis] : FLT_MAX;
 
 	if (p_axis >= AXIS_LINEAR_X && p_axis <= AXIS_LINEAR_Z) {

diff --git a/src/joints/jolt_hinge_joint_impl_3d.cpp b/src/joints/jolt_hinge_joint_impl_3d.cpp
@@ -379,7 +379,7 @@ void JoltHingeJointImpl3D::_update_motor_velocity() {
 	QUIET_FAIL_COND(_is_fixed());
 
 	if (auto* constraint = static_cast<JPH::HingeConstraint*>(jolt_ref.GetPtr())) {
-		// HACK(mihe): We're forced to flip the direction of these to match Godot Physics.
+		// NOTE(mihe): We flip the direction since Jolt is CCW but Godot is CW.
 		constraint->SetTargetAngularVelocity((float)-motor_target_speed);
 	}
 }

diff --git a/src/joints/jolt_joint_impl_3d.cpp b/src/joints/jolt_joint_impl_3d.cpp
@@ -179,10 +179,6 @@ void JoltJointImpl3D::_shift_reference_frames(
 	const Basis& basis_a = local_ref_a.basis;
 	const Basis& basis_b = local_ref_b.basis;
 
-	// HACK(mihe): Ideally we would add the linear shift here, not subtract it, but this is how
-	// Godot Physics seems to behave, so we emulate that. This does have the annoying side-effect of
-	// effectively making the upper limit instead be the lower limit and vice versa.
-
 	const Basis shifted_basis_a = basis_a * Basis::from_euler(p_angular_shift);
 	const Vector3 shifted_origin_a = origin_a - basis_a.xform(p_linear_shift);