diff options
Diffstat (limited to 'examples2d')
| -rw-r--r-- | examples2d/all_examples2.rs | 2 | ||||
| -rw-r--r-- | examples2d/damping2.rs | 2 | ||||
| -rw-r--r-- | examples2d/one_way_platforms2.rs | 143 |
3 files changed, 146 insertions, 1 deletions
diff --git a/examples2d/all_examples2.rs b/examples2d/all_examples2.rs index 5040c8a..f4430aa 100644 --- a/examples2d/all_examples2.rs +++ b/examples2d/all_examples2.rs @@ -18,6 +18,7 @@ mod debug_box_ball2; mod heightfield2; mod joints2; mod locked_rotations2; +mod one_way_platforms2; mod platform2; mod polyline2; mod pyramid2; @@ -65,6 +66,7 @@ pub fn main() { ("Heightfield", heightfield2::init_world), ("Joints", joints2::init_world), ("Locked rotations", locked_rotations2::init_world), + ("One-way platforms", one_way_platforms2::init_world), ("Platform", platform2::init_world), ("Polyline", polyline2::init_world), ("Pyramid", pyramid2::init_world), diff --git a/examples2d/damping2.rs b/examples2d/damping2.rs index 43ca2b6..68fd77d 100644 --- a/examples2d/damping2.rs +++ b/examples2d/damping2.rs @@ -40,6 +40,6 @@ pub fn init_world(testbed: &mut Testbed) { /* * Set up the testbed. */ - testbed.set_world_with_gravity(bodies, colliders, joints, Vector2::zeros()); + testbed.set_world_with_params(bodies, colliders, joints, Vector2::zeros(), ()); testbed.look_at(Point2::new(3.0, 2.0), 50.0); } diff --git a/examples2d/one_way_platforms2.rs b/examples2d/one_way_platforms2.rs new file mode 100644 index 0000000..551eaf1 --- /dev/null +++ b/examples2d/one_way_platforms2.rs @@ -0,0 +1,143 @@ +use na::{Point2, Vector2}; +use rapier2d::dynamics::{JointSet, RigidBodyBuilder, RigidBodySet}; +use rapier2d::geometry::{ColliderBuilder, ColliderHandle, ColliderSet}; +use rapier2d::pipeline::{ContactModificationContext, PhysicsHooks, PhysicsHooksFlags}; +use rapier_testbed2d::Testbed; + +struct OneWayPlatformHook { + platform1: ColliderHandle, + platform2: ColliderHandle, +} + +impl PhysicsHooks for OneWayPlatformHook { + fn active_hooks(&self) -> PhysicsHooksFlags { + PhysicsHooksFlags::MODIFY_SOLVER_CONTACTS + } + + fn modify_solver_contacts(&self, context: &mut ContactModificationContext) { + // The allowed normal for the first platform is its local +y axis, and the + // allowed normal for the second platform is its local -y axis. + // + // Now we have to be careful because the `manifold.local_n1` normal points + // toward the outside of the shape of `context.co1`. So we need to flip the + // allowed normal direction if the platform is in `context.collider_handle2`. + // + // Therefore: + // - If context.collider_handle1 == self.platform1 then the allowed normal is +y. + // - If context.collider_handle2 == self.platform1 then the allowed normal is -y. + // - If context.collider_handle1 == self.platform2 then its allowed normal +y needs to be flipped to -y. + // - If context.collider_handle2 == self.platform2 then the allowed normal -y needs to be flipped to +y. + let mut allowed_local_n1 = Vector2::zeros(); + + if context.collider_handle1 == self.platform1 { + allowed_local_n1 = Vector2::y(); + } else if context.collider_handle2 == self.platform1 { + // Flip the allowed direction. + allowed_local_n1 = -Vector2::y(); + } + + if context.collider_handle1 == self.platform2 { + allowed_local_n1 = -Vector2::y(); + } else if context.collider_handle2 == self.platform2 { + // Flip the allowed direction. + allowed_local_n1 = -Vector2::y(); + } + + // Call the helper function that simulates one-way platforms. + context.update_as_oneway_platform(&allowed_local_n1, 0.1); + + // Set the surface velocity of the accepted contacts. + let tangent_velocity = if context.collider_handle1 == self.platform1 + || context.collider_handle2 == self.platform2 + { + -12.0 + } else { + 12.0 + }; + + for contact in context.solver_contacts.iter_mut() { + contact.tangent_velocity.x = tangent_velocity; + } + } +} + +pub fn init_world(testbed: &mut Testbed) { + /* + * World + */ + let mut bodies = RigidBodySet::new(); + let mut colliders = ColliderSet::new(); + let joints = JointSet::new(); + + /* + * Ground + */ + let rigid_body = RigidBodyBuilder::new_static().build(); + let handle = bodies.insert(rigid_body); + + let collider = ColliderBuilder::cuboid(25.0, 0.5) + .translation(30.0, 2.0) + .modify_solver_contacts(true) + .build(); + let platform1 = colliders.insert(collider, handle, &mut bodies); + let collider = ColliderBuilder::cuboid(25.0, 0.5) + .translation(-30.0, -2.0) + .modify_solver_contacts(true) + .build(); + let platform2 = colliders.insert(collider, handle, &mut bodies); + + /* + * Setup the one-way platform hook. + */ + let physics_hooks = OneWayPlatformHook { + platform1, + platform2, + }; + + /* + * Spawn cubes at regular intervals and apply a custom gravity + * depending on their position. + */ + testbed.add_callback(move |mut window, mut graphics, physics, _, run_state| { + if run_state.timestep_id % 50 == 0 && physics.bodies.len() <= 7 { + // Spawn a new cube. + let collider = ColliderBuilder::cuboid(1.5, 2.0).build(); + let body = RigidBodyBuilder::new_dynamic() + .translation(20.0, 10.0) + .build(); + let handle = physics.bodies.insert(body); + physics + .colliders + .insert(collider, handle, &mut physics.bodies); + + if let (Some(graphics), Some(window)) = (&mut graphics, &mut window) { + graphics.add(window, handle, &physics.bodies, &physics.colliders); + } + } + + physics.bodies.foreach_active_dynamic_body_mut(|_, body| { + if body.position().translation.y > 1.0 { + body.set_gravity_scale(1.0, false); + } else if body.position().translation.y < -1.0 { + body.set_gravity_scale(-1.0, false); + } + }); + }); + + /* + * Set up the testbed. + */ + testbed.set_world_with_params( + bodies, + colliders, + joints, + Vector2::new(0.0, -9.81), + physics_hooks, + ); + testbed.look_at(Point2::new(0.0, 0.0), 20.0); +} + +fn main() { + let testbed = Testbed::from_builders(0, vec![("Boxes", init_world)]); + testbed.run() +} |