Add axels to the wheels.

src/action/systems.rs

@@ -32,7 +32,8 @@ pub(super) fn gravity(
     settings: Res<MovementSettings>,
 ) {
     let (xform, mut forces, mprops) = query.single_mut();
-    let grav = xform.translation.normalize() * -settings.gravity * mprops.0.mass;
+    //let grav = xform.translation.normalize() * -settings.gravity * mprops.0.mass;
+    let grav = Vec3::Y * -settings.gravity * mprops.0.mass;
     forces.force = grav;
     forces.torque = Vec3::ZERO;
 }
@@ -45,7 +46,8 @@ pub(super) fn falling_cat(
     #[cfg(feature = "inspector")] mut debug_instant: ResMut<ActionDebugInstant>,
 ) {
     let (xform, mut forces, mut control_vars) = bike_query.single_mut();
-    let wup = xform.translation.normalize();
+    //let wup = xform.translation.normalize();
+    let wup = Vec3::Y;
     let bike_up = xform.up();
 
     let wright = xform.forward().cross(wup).normalize();

src/bike/body.rs

@@ -51,7 +51,7 @@ pub(super) fn spawn_cyberbike(
         .spawn(RigidBody::Dynamic)
         .insert(spatialbundle)
         .insert((
-            Collider::capsule(Vec3::new(0.0, 0.0, -0.7), Vec3::new(0.0, 0.0, 1.0), 0.50),
+            Collider::capsule(Vec3::new(0.0, 0.0, -0.65), Vec3::new(0.0, 0.0, 0.8), 0.50),
             bike_collision_group,
             mass_properties,
             damping,

src/bike/wheels.rs

@@ -1,7 +1,7 @@
 use bevy::prelude::{shape::UVSphere as Tire, *};
 use bevy_rapier3d::prelude::{
     Ccd, Collider, ColliderMassProperties, CollisionGroups, Damping, ExternalForce, Friction,
-    MultibodyJoint, PrismaticJointBuilder, Restitution, RigidBody, Sleeping,
+    MultibodyJoint, PrismaticJointBuilder, Restitution, RevoluteJointBuilder, RigidBody, Sleeping,
     TransformInterpolation,
 };
 
@@ -80,19 +80,25 @@ pub fn spawn_tires(
         let mass_props = ColliderMassProperties::Density(0.1);
 
         let damping = conf.damping;
-        let prismatic = PrismaticJointBuilder::new(Vec3::Y)
+        let prismatic_builder = PrismaticJointBuilder::new(Vec3::Y)
             .local_anchor1(offset)
             .limits(limits)
-            .motor_position(-0.1, stiffness, damping);
-        let joint = MultibodyJoint::new(bike, prismatic);
+            .motor_position(limits[0], stiffness, damping);
+        let prismatic_joint = MultibodyJoint::new(bike, prismatic_builder);
+
+        let fork_rb_entity = commands
+            .spawn(RigidBody::Dynamic)
+            .insert(prismatic_joint)
+            .id();
+
+        let revolute_builder = RevoluteJointBuilder::new(Vec3::X);
+        let axel_joint = MultibodyJoint::new(fork_rb_entity, revolute_builder);
 
         let spatial_bundle = SpatialBundle {
-            transform: wheel_pos_in_world,
             ..Default::default()
         };
 
         let tire_spundle = SpatialBundle {
-            transform: Transform::IDENTITY,
             ..Default::default()
         };
 
@@ -105,7 +111,7 @@ pub fn spawn_tires(
                 wheel_damping,
                 ccd,
                 not_sleeping,
-                joint,
+                axel_joint,
                 wheels_collision_group,
                 friction,
                 CyberWheel,

src/input.rs

@@ -16,8 +16,8 @@ fn update_debug_cam(mut offset: ResMut<DebugCamOffset>, mut keys: ResMut<Input<K
 
     for key in keyset {
         match key {
-            KeyCode::Left => offset.rot += 5.0,
-            KeyCode::Right => offset.rot -= 5.0,
+            KeyCode::Left => offset.rot -= 5.0,
+            KeyCode::Right => offset.rot += 5.0,
             KeyCode::Up => {
                 if shifted {
                     offset.alt += 0.5;