Merge pull request #28 from dimforge/raycast

Add the QueryPipeline for ray-casting and other geometrical queries in the future

4 files changed, 163 insertions, 49 deletions

diff --git a/src/dynamics/integration_parameters.rs b/src/dynamics/integration_parameters.rs
index faf22e1..b31c3f6 100644
--- a/src/dynamics/integration_parameters.rs
+++ b/src/dynamics/integration_parameters.rs
@@ -2,7 +2,7 @@
 #[derive(Clone)]
 #[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
 pub struct IntegrationParameters {
-    /// The timestep (default: `1.0 / 60.0`)
+    /// The timestep length (default: `1.0 / 60.0`)
     dt: f32,
     /// The inverse of `dt`.
     inv_dt: f32,
diff --git a/src/dynamics/joint/joint_set.rs b/src/dynamics/joint/joint_set.rs
index 51d7432..2b1895f 100644
--- a/src/dynamics/joint/joint_set.rs
+++ b/src/dynamics/joint/joint_set.rs
@@ -66,17 +66,21 @@ impl JointSet {
     }
 
     /// Iterates through all the joint on this set.
-    pub fn iter(&self) -> impl Iterator<Item = &Joint> {
-        self.joint_graph.graph.edges.iter().map(|e| &e.weight)
+    pub fn iter(&self) -> impl Iterator<Item = (JointHandle, &Joint)> {
+        self.joint_graph
+            .graph
+            .edges
+            .iter()
+            .map(|e| (e.weight.handle, &e.weight))
     }
 
     /// Iterates mutably through all the joint on this set.
-    pub fn iter_mut(&mut self) -> impl Iterator<Item = &mut Joint> {
+    pub fn iter_mut(&mut self) -> impl Iterator<Item = (JointHandle, &mut Joint)> {
         self.joint_graph
             .graph
             .edges
             .iter_mut()
-            .map(|e| &mut e.weight)
+            .map(|e| (e.weight.handle, &mut e.weight))
     }
 
     // /// The set of joints as an array.
@@ -202,8 +206,8 @@ impl JointSet {
                 }
 
                 // Wake up the attached bodies.
-                bodies.wake_up(h1);
-                bodies.wake_up(h2);
+                bodies.wake_up(h1, true);
+                bodies.wake_up(h2, true);
             }
 
             if let Some(other) = self.joint_graph.remove_node(deleted_id) {
diff --git a/src/dynamics/rigid_body.rs b/src/dynamics/rigid_body.rs
index a2fcacc..af1fb4a 100644
--- a/src/dynamics/rigid_body.rs
+++ b/src/dynamics/rigid_body.rs
@@ -137,6 +137,15 @@ impl RigidBody {
         crate::utils::inv(self.mass_properties.inv_mass)
     }
 
+    /// The predicted position of this rigid-body.
+    ///
+    /// If this rigid-body is kinematic this value is set by the `set_next_kinematic_position`
+    /// method and is used for estimating the kinematic body velocity at the next timestep.
+    /// For non-kinematic bodies, this value is currently unspecified.
+    pub fn predicted_position(&self) -> &Isometry<f32> {
+        &self.predicted_position
+    }
+
     /// Adds a collider to this rigid-body.
     pub(crate) fn add_collider_internal(&mut self, handle: ColliderHandle, coll: &Collider) {
         let mass_properties = coll
@@ -172,10 +181,13 @@ impl RigidBody {
     }
 
     /// Wakes up this rigid body if it is sleeping.
-    pub fn wake_up(&mut self) {
+    ///
+    /// If `strong` is `true` then it is assured that the rigid-body will
+    /// remain awake during multiple subsequent timesteps.
+    pub fn wake_up(&mut self, strong: bool) {
         self.activation.sleeping = false;
 
-        if self.activation.energy == 0.0 && self.is_dynamic() {
+        if (strong || self.activation.energy == 0.0) && self.is_dynamic() {
             self.activation.energy = self.activation.threshold.abs() * 2.0;
         }
     }
@@ -189,9 +201,18 @@ impl RigidBody {
 
     /// Is this rigid body sleeping?
     pub fn is_sleeping(&self) -> bool {
+        // TODO: should we:
+        // - return false for static bodies.
+        // - return true for non-sleeping dynamic bodies.
+        // - return true only for kinematic bodies with non-zero velocity?
         self.activation.sleeping
     }
 
+    /// Is the velocity of this body not zero?
+    pub fn is_moving(&self) -> bool {
+        !self.linvel.is_zero() || !self.angvel.is_zero()
+    }
+
     fn integrate_velocity(&self, dt: f32) -> Isometry<f32> {
         let com = &self.position * self.mass_properties.local_com;
         let shift = Translation::from(com.coords);
@@ -201,12 +222,17 @@ impl RigidBody {
         self.position = self.integrate_velocity(dt) * self.position;
     }
 
-    /// Sets the position of this rigid body.
+    /// Sets the position and `next_kinematic_position` of this rigid body.
+    ///
+    /// This will teleport the rigid-body to the specified position/orientation,
+    /// completely ignoring any physics rule. If this body is kinematic, this will
+    /// also set the next kinematic position to the same value, effectively
+    /// resetting to zero the next interpolated velocity of the kinematic body.
     pub fn set_position(&mut self, pos: Isometry<f32>) {
         self.position = pos;
 
         // TODO: update the predicted position for dynamic bodies too?
-        if self.is_static() {
+        if self.is_static() || self.is_kinematic() {
             self.predicted_position = pos;
         }
     }
diff --git a/src/dynamics/rigid_body_set.rs b/src/dynamics/rigid_body_set.rs
index 99d6f10..83f1c51 100644
--- a/src/dynamics/rigid_body_set.rs
+++ b/src/dynamics/rigid_body_set.rs
@@ -2,8 +2,8 @@
 use rayon::prelude::*;
 
 use crate::data::arena::Arena;
-use crate::dynamics::{Joint, RigidBody};
-use crate::geometry::{ColliderSet, ContactPair, InteractionGraph};
+use crate::dynamics::{BodyStatus, Joint, JointSet, RigidBody};
+use crate::geometry::{ColliderHandle, ColliderSet, ContactPair, InteractionGraph};
 use crossbeam::channel::{Receiver, Sender};
 use std::ops::{Deref, DerefMut, Index, IndexMut};
 
@@ -128,9 +128,23 @@ impl RigidBodySet {
 
     pub(crate) fn activate(&mut self, handle: RigidBodyHandle) {
         let mut rb = &mut self.bodies[handle];
-        if self.active_dynamic_set.get(rb.active_set_id) != Some(&handle) {
-            rb.active_set_id = self.active_dynamic_set.len();
-            self.active_dynamic_set.push(handle);
+        match rb.body_status {
+            // XXX: this case should only concern the dynamic bodies.
+            // For static bodies we should use the modified_inactive_set, or something
+            // similar. Right now we do this for static bodies as well so the broad-phase
+            // takes them into account the first time they are inserted.
+            BodyStatus::Dynamic | BodyStatus::Static => {
+                if self.active_dynamic_set.get(rb.active_set_id) != Some(&handle) {
+                    rb.active_set_id = self.active_dynamic_set.len();
+                    self.active_dynamic_set.push(handle);
+                }
+            }
+            BodyStatus::Kinematic => {
+                if self.active_kinematic_set.get(rb.active_set_id) != Some(&handle) {
+                    rb.active_set_id = self.active_kinematic_set.len();
+                    self.active_kinematic_set.push(handle);
+                }
+            }
         }
     }
 
@@ -143,13 +157,14 @@ impl RigidBodySet {
     pub fn insert(&mut self, rb: RigidBody) -> RigidBodyHandle {
         let handle = self.bodies.insert(rb);
         let rb = &mut self.bodies[handle];
-        rb.active_set_id = self.active_dynamic_set.len();
 
         if !rb.is_sleeping() && rb.is_dynamic() {
+            rb.active_set_id = self.active_dynamic_set.len();
             self.active_dynamic_set.push(handle);
         }
 
         if rb.is_kinematic() {
+            rb.active_set_id = self.active_kinematic_set.len();
             self.active_kinematic_set.push(handle);
         }
 
@@ -160,29 +175,57 @@ impl RigidBodySet {
         handle
     }
 
-    pub(crate) fn num_islands(&self) -> usize {
-        self.active_islands.len() - 1
-    }
-
-    pub(crate) fn remove_internal(&mut self, handle: RigidBodyHandle) -> Option<RigidBody> {
+    /// Removes a rigid-body, and all its attached colliders and joints, from these sets.
+    pub fn remove(
+        &mut self,
+        handle: RigidBodyHandle,
+        colliders: &mut ColliderSet,
+        joints: &mut JointSet,
+    ) -> Option<RigidBody> {
         let rb = self.bodies.remove(handle)?;
-        // Remove this body from the active dynamic set.
-        if self.active_dynamic_set.get(rb.active_set_id) == Some(&handle) {
-            self.active_dynamic_set.swap_remove(rb.active_set_id);
+        /*
+         * Update active sets.
+         */
+        let mut active_sets = [&mut self.active_kinematic_set, &mut self.active_dynamic_set];
+
+        for active_set in &mut active_sets {
+            if active_set.get(rb.active_set_id) == Some(&handle) {
+                active_set.swap_remove(rb.active_set_id);
 
-            if let Some(replacement) = self.active_dynamic_set.get(rb.active_set_id) {
-                self.bodies[*replacement].active_set_id = rb.active_set_id;
+                if let Some(replacement) = active_set.get(rb.active_set_id) {
+                    self.bodies[*replacement].active_set_id = rb.active_set_id;
+                }
             }
         }
 
+        /*
+         * Remove colliders attached to this rigid-body.
+         */
+        for collider in &rb.colliders {
+            colliders.remove(*collider, self);
+        }
+
+        /*
+         * Remove joints attached to this rigid-body.
+         */
+        joints.remove_rigid_body(rb.joint_graph_index, self);
+
         Some(rb)
     }
 
+    pub(crate) fn num_islands(&self) -> usize {
+        self.active_islands.len() - 1
+    }
+
     /// Forces the specified rigid-body to wake up if it is dynamic.
-    pub fn wake_up(&mut self, handle: RigidBodyHandle) {
+    ///
+    /// If `strong` is `true` then it is assured that the rigid-body will
+    /// remain awake during multiple subsequent timesteps.
+    pub fn wake_up(&mut self, handle: RigidBodyHandle, strong: bool) {
         if let Some(rb) = self.bodies.get_mut(handle) {
+            // TODO: what about kinematic bodies?
             if rb.is_dynamic() {
-                rb.wake_up();
+                rb.wake_up(strong);
 
                 if self.active_dynamic_set.get(rb.active_set_id) != Some(&handle) {
                     rb.active_set_id = self.active_dynamic_set.len();
@@ -214,8 +257,11 @@ impl RigidBodySet {
     ///
     /// Using this is discouraged in favor of `self.get_mut(handle)` which does not
     /// suffer form the ABA problem.
-    pub fn get_unknown_gen_mut(&mut self, i: usize) -> Option<(&mut RigidBody, RigidBodyHandle)> {
-        self.bodies.get_unknown_gen_mut(i)
+    pub fn get_unknown_gen_mut(&mut self, i: usize) -> Option<(RigidBodyMut, RigidBodyHandle)> {
+        let sender = &self.activation_channel.0;
+        self.bodies
+            .get_unknown_gen_mut(i)
+            .map(|(rb, handle)| (RigidBodyMut::new(handle, rb, sender), handle))
     }
 
     /// Gets the rigid-body with the given handle.
@@ -256,6 +302,16 @@ impl RigidBodySet {
             .map(move |(h, rb)| (h, RigidBodyMut::new(h, rb, sender)))
     }
 
+    /// Iter through all the active kinematic rigid-bodies on this set.
+    pub fn iter_active_kinematic<'a>(
+        &'a self,
+    ) -> impl Iterator<Item = (RigidBodyHandle, &'a RigidBody)> {
+        let bodies: &'a _ = &self.bodies;
+        self.active_kinematic_set
+            .iter()
+            .filter_map(move |h| Some((*h, bodies.get(*h)?)))
+    }
+
     /// Iter through all the active dynamic rigid-bodies on this set.
     pub fn iter_active_dynamic<'a>(
         &'a self,
@@ -425,6 +481,45 @@ impl RigidBodySet {
             }
         }
 
+        // Read all the contacts and push objects touching touching this rigid-body.
+        #[inline(always)]
+        fn push_contacting_colliders(
+            rb: &RigidBody,
+            colliders: &ColliderSet,
+            contact_graph: &InteractionGraph<ContactPair>,
+            stack: &mut Vec<ColliderHandle>,
+        ) {
+            for collider_handle in &rb.colliders {
+                let collider = &colliders[*collider_handle];
+
+                for inter in contact_graph.interactions_with(collider.contact_graph_index) {
+                    for manifold in &inter.2.manifolds {
+                        if manifold.num_active_contacts() > 0 {
+                            let other =
+                                crate::utils::other_handle((inter.0, inter.1), *collider_handle);
+                            let other_body = colliders[other].parent;
+                            stack.push(other_body);
+                            break;
+                        }
+                    }
+                }
+            }
+        }
+
+        // Now iterate on all active kinematic bodies and push all the bodies
+        // touching them to the stack so they can be woken up.
+        for h in self.active_kinematic_set.iter() {
+            let rb = &self.bodies[*h];
+
+            if !rb.is_moving() {
+                // If the kinematic body does not move, it does not have
+                // to wake up any dynamic body.
+                continue;
+            }
+
+            push_contacting_colliders(rb, colliders, contact_graph, &mut self.stack);
+        }
+
         //        println!("Selection: {}", instant::now() - t);
 
         //        let t = instant::now();
@@ -443,7 +538,9 @@ impl RigidBodySet {
                 // We already visited this body and its neighbors.
                 // Also, we don't propagate awake state through static bodies.
                 continue;
-            } else if self.stack.len() < island_marker {
+            }
+
+            if self.stack.len() < island_marker {
                 if self.active_dynamic_set.len() - *self.active_islands.last().unwrap()
                     >= min_island_size
                 {
@@ -454,29 +551,16 @@ impl RigidBodySet {
                 island_marker = self.stack.len();
             }
 
-            rb.wake_up();
+            rb.wake_up(false);
             rb.active_island_id = self.active_islands.len() - 1;
             rb.active_set_id = self.active_dynamic_set.len();
             rb.active_set_offset = rb.active_set_id - self.active_islands[rb.active_island_id];
             rb.active_set_timestamp = self.active_set_timestamp;
             self.active_dynamic_set.push(handle);
 
-            // Read all the contacts and push objects touching this one.
-            for collider_handle in &rb.colliders {
-                let collider = &colliders[*collider_handle];
-
-                for inter in contact_graph.interactions_with(collider.contact_graph_index) {
-                    for manifold in &inter.2.manifolds {
-                        if manifold.num_active_contacts() > 0 {
-                            let other =
-                                crate::utils::other_handle((inter.0, inter.1), *collider_handle);
-                            let other_body = colliders[other].parent;
-                            self.stack.push(other_body);
-                            break;
-                        }
-                    }
-                }
-            }
+            // Transmit the active state to all the rigid-bodies with colliders
+            // in contact or joined with this collider.
+            push_contacting_colliders(rb, colliders, contact_graph, &mut self.stack);
 
             for inter in joint_graph.interactions_with(rb.joint_graph_index) {
                 let other = crate::utils::other_handle((inter.0, inter.1), handle);