impl PartialEq for Shapes, and SharedShape

fixes #51

src/shape/capsule.rs

@@ -8,7 +8,7 @@ use either::Either;
 #[cfg(feature = "rkyv")]
 use rkyv::{bytecheck, CheckBytes};
 
-#[derive(Copy, Clone, Debug)]
+#[derive(Copy, Clone, Debug, PartialEq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 #[cfg_attr(feature = "bytemuck", derive(bytemuck::Pod, bytemuck::Zeroable))]
 #[cfg_attr(

src/shape/compound.rs

@@ -26,6 +26,12 @@ pub struct Compound {
     aabb: Aabb,
 }
 
+impl PartialEq for Compound {
+    fn eq(&self, other: &Self) -> bool {
+        self.shapes() == other.shapes()
+    }
+}
+
 impl Compound {
     /// Builds a new compound shape.
     ///

src/shape/convex_polygon.rs

@@ -10,7 +10,7 @@ use na::{self, ComplexField, RealField, Unit};
     derive(rkyv::Archive, rkyv::Deserialize, rkyv::Serialize),
     archive(check_bytes)
 )]
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, PartialEq)]
 pub struct ConvexPolygon {
     points: Vec<Point<Real>>,
     normals: Vec<Unit<Vector<Real>>>,

src/shape/polyline.rs

@@ -23,6 +23,12 @@ pub struct Polyline {
     indices: Vec<[u32; 2]>,
 }
 
+impl PartialEq for Polyline {
+    fn eq(&self, other: &Self) -> bool {
+        self.indices() == other.indices() && self.vertices() == other.vertices()
+    }
+}
+
 impl Polyline {
     /// Creates a new polyline from a vertex buffer and an index buffer.
     pub fn new(vertices: Vec<Point<Real>>, indices: Option<Vec<[u32; 2]>>) -> Self {

src/shape/round_shape.rs

@@ -9,7 +9,7 @@ use na::Unit;
     archive(check_bytes)
 )]
 #[cfg_attr(feature = "cuda", derive(cust_core::DeviceCopy))]
-#[derive(Copy, Clone, Debug)]
+#[derive(Copy, Clone, Debug, PartialEq)]
 #[repr(C)]
 /// A shape with rounded borders.
 pub struct RoundShape<S> {

src/shape/shared_shape.rs

@@ -14,6 +14,8 @@ use na::Unit;
 use std::ops::Deref;
 use std::sync::Arc;
 
+use super::TypedShape;
+
 /// The shape of a collider.
 #[derive(Clone)]
 pub struct SharedShape(pub Arc<dyn Shape>);
@@ -384,3 +386,47 @@ impl<'de> serde::Deserialize<'de> for SharedShape {
             .ok_or(D::Error::custom("Cannot deserialize custom shape."))
     }
 }
+
+impl PartialEq for SharedShape {
+    fn eq(&self, other: &Self) -> bool {
+        // shapes with different types can't be equal.
+        if self.shape_type() != other.shape_type() {
+            return false;
+        }
+        match self.as_typed_shape() {
+            TypedShape::Ball(shape) => shape == other.as_ball().unwrap(),
+            TypedShape::Cuboid(shape) => shape == other.as_cuboid().unwrap(),
+            TypedShape::RoundCuboid(shape) => shape == other.as_round_cuboid().unwrap(),
+            TypedShape::Capsule(shape) => shape == other.as_capsule().unwrap(),
+            TypedShape::Segment(shape) => shape == other.as_segment().unwrap(),
+            TypedShape::Triangle(shape) => shape == other.as_triangle().unwrap(),
+            TypedShape::RoundTriangle(shape) => shape == other.as_round_triangle().unwrap(),
+            TypedShape::TriMesh(shape) => shape == other.as_trimesh().unwrap(),
+            TypedShape::Polyline(shape) => shape == other.as_polyline().unwrap(),
+            TypedShape::HalfSpace(shape) => shape == other.as_halfspace().unwrap(),
+            TypedShape::HeightField(_) => false,
+            TypedShape::Compound(shape) => shape == other.as_compound().unwrap(),
+            TypedShape::Custom(_) => false,
+            #[cfg(feature = "dim3")]
+            TypedShape::ConvexPolyhedron(shape) => shape == other.as_convex_polyhedron().unwrap(),
+            #[cfg(feature = "dim3")]
+            TypedShape::Cylinder(shape) => shape == other.as_cylinder().unwrap(),
+            #[cfg(feature = "dim3")]
+            TypedShape::Cone(shape) => shape == other.as_cone().unwrap(),
+            #[cfg(feature = "dim3")]
+            TypedShape::RoundCylinder(shape) => shape == other.as_round_cylinder().unwrap(),
+            #[cfg(feature = "dim3")]
+            TypedShape::RoundCone(shape) => shape == other.as_round_cone().unwrap(),
+            #[cfg(feature = "dim3")]
+            TypedShape::RoundConvexPolyhedron(shape) => {
+                shape == other.as_round_convex_polyhedron().unwrap()
+            }
+            #[cfg(feature = "dim2")]
+            TypedShape::ConvexPolygon(shape) => shape == other.as_convex_polygon().unwrap(),
+            #[cfg(feature = "dim2")]
+            TypedShape::RoundConvexPolygon(shape) => {
+                shape == other.as_round_convex_polygon().unwrap()
+            }
+        }
+    }
+}

src/shape/trimesh.rs

@@ -358,6 +358,22 @@ pub struct GenericTriMesh<Storage: TriMeshStorage> {
     flags: TriMeshFlags,
 }
 
+impl PartialEq for TriMesh {
+    fn eq(&self, other: &Self) -> bool {
+        let triangles = self.triangles();
+        let other_triangles = other.triangles();
+        if triangles.len() != other_triangles.len() {
+            return false;
+        }
+        for (t1, t2) in triangles.zip(other_triangles) {
+            if t1 != t2 {
+                return false;
+            }
+        }
+        true
+    }
+}
+
 /// A triangle-mesh.
 pub type TriMesh = GenericTriMesh<DefaultStorage>;
 #[cfg(feature = "cuda")]