Allow several rules for combining friction/restitution coefficients.

1 files changed, 51 insertions, 293 deletions

diff --git a/src/geometry/collider.rs b/src/geometry/collider.rs
index a4de108..c5f53f7 100644
--- a/src/geometry/collider.rs
+++ b/src/geometry/collider.rs
@@ -1,309 +1,44 @@
-use crate::dynamics::{MassProperties, RigidBodyHandle};
-use crate::geometry::InteractionGroups;
+use crate::dynamics::{CoefficientCombineRule, MassProperties, RigidBodyHandle};
+use crate::geometry::{ColliderShape, InteractionGroups};
 use crate::math::{AngVector, Isometry, Point, Real, Rotation, Vector};
 use cdl::bounding_volume::AABB;
-use cdl::shape::{
-    Ball, Capsule, Compound, Cuboid, HalfSpace, HeightField, RoundCuboid, RoundShape,
-    RoundTriangle, Segment, Shape, ShapeType, TriMesh, Triangle,
-};
-#[cfg(feature = "dim3")]
-use cdl::shape::{
-    Cone, ConvexPolyhedron, Cylinder, RoundCone, RoundConvexPolyhedron, RoundCylinder,
-};
+use cdl::shape::Shape;
 #[cfg(feature = "dim2")]
 use cdl::shape::{ConvexPolygon, RoundConvexPolygon};
-use std::ops::Deref;
-use std::sync::Arc;
 
-// TODO: move this to its own file.
-/// The shape of a collider.
-#[derive(Clone)]
-pub struct ColliderShape(pub Arc<dyn Shape>);
-
-impl Deref for ColliderShape {
-    type Target = dyn Shape;
-    fn deref(&self) -> &dyn Shape {
-        &*self.0
+bitflags::bitflags! {
+    #[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
+    /// Flags affecting the behavior of the constraints solver for a given contact manifold.
+    pub(crate) struct ColliderFlags: u8 {
+        const SENSOR = 1 << 0;
+        const FRICTION_COMBINE_RULE_01 = 1 << 1;
+        const FRICTION_COMBINE_RULE_10 = 1 << 2;
+        const RESTITUTION_COMBINE_RULE_01 = 1 << 3;
+        const RESTITUTION_COMBINE_RULE_10 = 1 << 4;
     }
 }
 
-impl ColliderShape {
-    /// Initialize a compound shape defined by its subshapes.
-    pub fn compound(shapes: Vec<(Isometry<Real>, ColliderShape)>) -> Self {
-        let raw_shapes = shapes.into_iter().map(|s| (s.0, s.1 .0)).collect();
-        let compound = Compound::new(raw_shapes);
-        ColliderShape(Arc::new(compound))
-    }
-
-    /// Initialize a ball shape defined by its radius.
-    pub fn ball(radius: Real) -> Self {
-        ColliderShape(Arc::new(Ball::new(radius)))
-    }
-
-    /// Initialize a cylindrical shape defined by its half-height
-    /// (along along the y axis) and its radius.
-    #[cfg(feature = "dim3")]
-    pub fn cylinder(half_height: Real, radius: Real) -> Self {
-        ColliderShape(Arc::new(Cylinder::new(half_height, radius)))
-    }
-
-    /// Initialize a rounded cylindrical shape defined by its half-height
-    /// (along along the y axis), its radius, and its roundedness (the
-    /// radius of the sphere used for dilating the cylinder).
-    #[cfg(feature = "dim3")]
-    pub fn round_cylinder(half_height: Real, radius: Real, border_radius: Real) -> Self {
-        ColliderShape(Arc::new(RoundShape {
-            base_shape: Cylinder::new(half_height, radius),
-            border_radius,
-        }))
-    }
-
-    /// Initialize a rounded cone shape defined by its half-height
-    /// (along along the y axis), its radius, and its roundedness (the
-    /// radius of the sphere used for dilating the cylinder).
-    #[cfg(feature = "dim3")]
-    pub fn round_cone(half_height: Real, radius: Real, border_radius: Real) -> Self {
-        ColliderShape(Arc::new(RoundShape {
-            base_shape: Cone::new(half_height, radius),
-            border_radius,
-        }))
-    }
-
-    /// Initialize a cone shape defined by its half-height
-    /// (along along the y axis) and its basis radius.
-    #[cfg(feature = "dim3")]
-    pub fn cone(half_height: Real, radius: Real) -> Self {
-        ColliderShape(Arc::new(Cone::new(half_height, radius)))
-    }
-
-    /// Initialize a cuboid shape defined by its half-extents.
-    #[cfg(feature = "dim2")]
-    pub fn cuboid(hx: Real, hy: Real) -> Self {
-        ColliderShape(Arc::new(Cuboid::new(Vector::new(hx, hy))))
-    }
-
-    /// Initialize a round cuboid shape defined by its half-extents and border radius.
-    #[cfg(feature = "dim2")]
-    pub fn round_cuboid(hx: Real, hy: Real, border_radius: Real) -> Self {
-        ColliderShape(Arc::new(RoundShape {
-            base_shape: Cuboid::new(Vector::new(hx, hy)),
-            border_radius,
-        }))
-    }
-
-    /// Initialize a cuboid shape defined by its half-extents.
-    #[cfg(feature = "dim3")]
-    pub fn cuboid(hx: Real, hy: Real, hz: Real) -> Self {
-        ColliderShape(Arc::new(Cuboid::new(Vector::new(hx, hy, hz))))
-    }
-
-    /// Initialize a round cuboid shape defined by its half-extents and border radius.
-    #[cfg(feature = "dim3")]
-    pub fn round_cuboid(hx: Real, hy: Real, hz: Real, border_radius: Real) -> Self {
-        ColliderShape(Arc::new(RoundShape {
-            base_shape: Cuboid::new(Vector::new(hx, hy, hz)),
-            border_radius,
-        }))
-    }
-
-    /// Initialize a capsule shape from its endpoints and radius.
-    pub fn capsule(a: Point<Real>, b: Point<Real>, radius: Real) -> Self {
-        ColliderShape(Arc::new(Capsule::new(a, b, radius)))
-    }
-
-    /// Initialize a segment shape from its endpoints.
-    pub fn segment(a: Point<Real>, b: Point<Real>) -> Self {
-        ColliderShape(Arc::new(Segment::new(a, b)))
-    }
-
-    /// Initializes a triangle shape.
-    pub fn triangle(a: Point<Real>, b: Point<Real>, c: Point<Real>) -> Self {
-        ColliderShape(Arc::new(Triangle::new(a, b, c)))
-    }
-
-    /// Initializes a triangle mesh shape defined by its vertex and index buffers.
-    pub fn trimesh(vertices: Vec<Point<Real>>, indices: Vec<[u32; 3]>) -> Self {
-        ColliderShape(Arc::new(TriMesh::new(vertices, indices)))
-    }
-
-    pub fn convex_hull(points: &[Point<Real>]) -> Option<Self> {
-        #[cfg(feature = "dim2")]
-        return ConvexPolygon::from_convex_hull(points).map(|ch| ColliderShape(Arc::new(ch)));
-        #[cfg(feature = "dim3")]
-        return ConvexPolyhedron::from_convex_hull(points).map(|ch| ColliderShape(Arc::new(ch)));
-    }
-
-    #[cfg(feature = "dim2")]
-    pub fn convex_polyline(points: Vec<Point<Real>>) -> Option<Self> {
-        ConvexPolygon::from_convex_polyline(points).map(|ch| ColliderShape(Arc::new(ch)))
-    }
-
-    #[cfg(feature = "dim3")]
-    pub fn convex_mesh(points: Vec<Point<Real>>, indices: &[[u32; 3]]) -> Option<Self> {
-        ConvexPolyhedron::from_convex_mesh(points, indices).map(|ch| ColliderShape(Arc::new(ch)))
-    }
-
-    pub fn round_convex_hull(points: &[Point<Real>], border_radius: Real) -> Option<Self> {
-        #[cfg(feature = "dim2")]
-        return ConvexPolygon::from_convex_hull(points).map(|ch| {
-            ColliderShape(Arc::new(RoundShape {
-                base_shape: ch,
-                border_radius,
-            }))
-        });
-        #[cfg(feature = "dim3")]
-        return ConvexPolyhedron::from_convex_hull(points).map(|ch| {
-            ColliderShape(Arc::new(RoundShape {
-                base_shape: ch,
-                border_radius,
-            }))
-        });
-    }
-
-    #[cfg(feature = "dim2")]
-    pub fn round_convex_polyline(points: Vec<Point<Real>>, border_radius: Real) -> Option<Self> {
-        ConvexPolygon::from_convex_polyline(points).map(|ch| {
-            ColliderShape(Arc::new(RoundShape {
-                base_shape: ch,
-                border_radius,
-            }))
-        })
-    }
-
-    #[cfg(feature = "dim3")]
-    pub fn round_convex_mesh(
-        points: Vec<Point<Real>>,
-        indices: &[[u32; 3]],
-        border_radius: Real,
-    ) -> Option<Self> {
-        ConvexPolyhedron::from_convex_mesh(points, indices).map(|ch| {
-            ColliderShape(Arc::new(RoundShape {
-                base_shape: ch,
-                border_radius,
-            }))
-        })
+impl ColliderFlags {
+    pub fn is_sensor(self) -> bool {
+        self.contains(ColliderFlags::SENSOR)
     }
 
-    /// Initializes an heightfield shape defined by its set of height and a scale
-    /// factor along each coordinate axis.
-    #[cfg(feature = "dim2")]
-    pub fn heightfield(heights: na::DVector<Real>, scale: Vector<Real>) -> Self {
-        ColliderShape(Arc::new(HeightField::new(heights, scale)))
+    pub fn friction_combine_rule_value(self) -> u8 {
+        (self.bits & 0b0000_0110) >> 1
     }
 
-    /// Initializes an heightfield shape on the x-z plane defined by its set of height and a scale
-    /// factor along each coordinate axis.
-    #[cfg(feature = "dim3")]
-    pub fn heightfield(heights: na::DMatrix<Real>, scale: Vector<Real>) -> Self {
-        ColliderShape(Arc::new(HeightField::new(heights, scale)))
+    pub fn restitution_combine_rule_value(self) -> u8 {
+        (self.bits & 0b0001_1000) >> 3
     }
-}
 
-#[cfg(feature = "serde-serialize")]
-impl serde::Serialize for ColliderShape {
-    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
-    where
-        S: serde::Serializer,
-    {
-        use crate::serde::ser::SerializeStruct;
-
-        if let Some(ser) = self.0.as_serialize() {
-            let typ = self.0.shape_type();
-            let mut state = serializer.serialize_struct("ColliderShape", 2)?;
-            state.serialize_field("tag", &(typ as i32))?;
-            state.serialize_field("inner", ser)?;
-            state.end()
-        } else {
-            Err(serde::ser::Error::custom(
-                "Found a non-serializable custom shape.",
-            ))
-        }
+    pub fn with_friction_combine_rule(mut self, rule: CoefficientCombineRule) -> Self {
+        self.bits = (self.bits & !0b0000_0110) | ((rule as u8) << 1);
+        self
     }
-}
 
-#[cfg(feature = "serde-serialize")]
-impl<'de> serde::Deserialize<'de> for ColliderShape {
-    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
-    where
-        D: serde::Deserializer<'de>,
-    {
-        struct Visitor {};
-        impl<'de> serde::de::Visitor<'de> for Visitor {
-            type Value = ColliderShape;
-            fn expecting(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
-                write!(formatter, "one shape type tag and the inner shape data")
-            }
-
-            fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
-            where
-                A: serde::de::SeqAccess<'de>,
-            {
-                use num::cast::FromPrimitive;
-
-                let tag: i32 = seq
-                    .next_element()?
-                    .ok_or_else(|| serde::de::Error::invalid_length(0, &self))?;
-
-                fn deser<'de, A, S: Shape + serde::Deserialize<'de>>(
-                    seq: &mut A,
-                ) -> Result<Arc<dyn Shape>, A::Error>
-                where
-                    A: serde::de::SeqAccess<'de>,
-                {
-                    let shape: S = seq.next_element()?.ok_or_else(|| {
-                        serde::de::Error::custom("Failed to deserialize builtin shape.")
-                    })?;
-                    Ok(Arc::new(shape) as Arc<dyn Shape>)
-                }
-
-                let shape = match ShapeType::from_i32(tag) {
-                    Some(ShapeType::Ball) => deser::<A, Ball>(&mut seq)?,
-                    Some(ShapeType::Cuboid) => deser::<A, Cuboid>(&mut seq)?,
-                    Some(ShapeType::Capsule) => deser::<A, Capsule>(&mut seq)?,
-                    Some(ShapeType::Triangle) => deser::<A, Triangle>(&mut seq)?,
-                    Some(ShapeType::Segment) => deser::<A, Segment>(&mut seq)?,
-                    Some(ShapeType::TriMesh) => deser::<A, TriMesh>(&mut seq)?,
-                    Some(ShapeType::HeightField) => deser::<A, HeightField>(&mut seq)?,
-                    Some(ShapeType::HalfSpace) => deser::<A, HalfSpace>(&mut seq)?,
-                    Some(ShapeType::RoundCuboid) => deser::<A, RoundCuboid>(&mut seq)?,
-                    Some(ShapeType::RoundTriangle) => deser::<A, RoundTriangle>(&mut seq)?,
-                    #[cfg(feature = "dim2")]
-                    Some(ShapeType::ConvexPolygon) => deser::<A, ConvexPolygon>(&mut seq)?,
-                    #[cfg(feature = "dim2")]
-                    Some(ShapeType::RoundConvexPolygon) => {
-                        deser::<A, RoundConvexPolygon>(&mut seq)?
-                    }
-                    #[cfg(feature = "dim3")]
-                    Some(ShapeType::Cylinder) => deser::<A, Cylinder>(&mut seq)?,
-                    #[cfg(feature = "dim3")]
-                    Some(ShapeType::ConvexPolyhedron) => deser::<A, ConvexPolyhedron>(&mut seq)?,
-                    #[cfg(feature = "dim3")]
-                    Some(ShapeType::Cone) => deser::<A, Cone>(&mut seq)?,
-                    #[cfg(feature = "dim3")]
-                    Some(ShapeType::RoundCylinder) => deser::<A, RoundCylinder>(&mut seq)?,
-                    #[cfg(feature = "dim3")]
-                    Some(ShapeType::RoundCone) => deser::<A, RoundCone>(&mut seq)?,
-                    #[cfg(feature = "dim3")]
-                    Some(ShapeType::RoundConvexPolyhedron) => {
-                        deser::<A, RoundConvexPolyhedron>(&mut seq)?
-                    }
-                    Some(ShapeType::Compound) => {
-                        return Err(serde::de::Error::custom(
-                            "found invalid shape type to deserialize",
-                        ))
-                    }
-                    None => {
-                        return Err(serde::de::Error::custom(
-                            "found invalid shape type to deserialize",
-                        ))
-                    }
-                };
-
-                Ok(ColliderShape(shape))
-            }
-        }
-
-        deserializer.deserialize_struct("ColliderShape", &["tag", "inner"], Visitor {})
+    pub fn with_restitution_combine_rule(mut self, rule: CoefficientCombineRule) -> Self {
+        self.bits = (self.bits & !0b0001_1000) | ((rule as u8) << 3);
+        self
     }
 }
 
@@ -315,7 +50,7 @@ impl<'de> serde::Deserialize<'de> for ColliderShape {
 pub struct Collider {
     shape: ColliderShape,
     density: Real,
-    is_sensor: bool,
+    pub(crate) flags: ColliderFlags,
     pub(crate) parent: RigidBodyHandle,
     pub(crate) delta: Isometry<Real>,
     pub(crate) position: Isometry<Real>,
@@ -344,7 +79,7 @@ impl Collider {
 
     /// Is this collider a sensor?
     pub fn is_sensor(&self) -> bool {
-        self.is_sensor
+        self.flags.is_sensor()
     }
 
     #[doc(hidden)]
@@ -415,8 +150,12 @@ pub struct ColliderBuilder {
     density: Option<Real>,
     /// The friction coefficient of the collider to be built.
     pub friction: Real,
+    /// The rule used to combine two friction coefficients.
+    pub friction_combine_rule: CoefficientCombineRule,
     /// The restitution coefficient of the collider to be built.
     pub restitution: Real,
+    /// The rule used to combine two restitution coefficients.
+    pub restitution_combine_rule: CoefficientCombineRule,
     /// The position of this collider relative to the local frame of the rigid-body it is attached to.
     pub delta: Isometry<Real>,
     /// Is this collider a sensor?
@@ -442,6 +181,8 @@ impl ColliderBuilder {
             user_data: 0,
             collision_groups: InteractionGroups::all(),
             solver_groups: InteractionGroups::all(),
+            friction_combine_rule: CoefficientCombineRule::Average,
+            restitution_combine_rule: CoefficientCombineRule::Average,
         }
     }
 
@@ -645,12 +386,24 @@ impl ColliderBuilder {
         self
     }
 
+    /// Sets the rule to be used to combine two friction coefficients in a contact.
+    pub fn friction_combine_rule(mut self, rule: CoefficientCombineRule) -> Self {
+        self.friction_combine_rule = rule;
+        self
+    }
+
     /// Sets the restitution coefficient of the collider this builder will build.
     pub fn restitution(mut self, restitution: Real) -> Self {
         self.restitution = restitution;
         self
     }
 
+    /// Sets the rule to be used to combine two restitution coefficients in a contact.
+    pub fn restitution_combine_rule(mut self, rule: CoefficientCombineRule) -> Self {
+        self.restitution_combine_rule = rule;
+        self
+    }
+
     /// Sets the density of the collider this builder will build.
     pub fn density(mut self, density: Real) -> Self {
         self.density = Some(density);
@@ -700,6 +453,11 @@ impl ColliderBuilder {
     /// Builds a new collider attached to the given rigid-body.
     pub fn build(&self) -> Collider {
         let density = self.get_density();
+        let mut flags = ColliderFlags::empty();
+        flags.set(ColliderFlags::SENSOR, self.is_sensor);
+        flags = flags
+            .with_friction_combine_rule(self.friction_combine_rule)
+            .with_restitution_combine_rule(self.restitution_combine_rule);
 
         Collider {
             shape: self.shape.clone(),
@@ -707,7 +465,7 @@ impl ColliderBuilder {
             friction: self.friction,
             restitution: self.restitution,
             delta: self.delta,
-            is_sensor: self.is_sensor,
+            flags,
             parent: RigidBodyHandle::invalid(),
             position: Isometry::identity(),
             predicted_position: Isometry::identity(),