add failing test

engine/physics/src/minimum_difference.rs

@@ -843,4 +843,33 @@ fn minimum_difference<const ENABLE_FAST_FAIL:bool,T,M:MeshQuery>(
 	}
 }
 
-// TODO: unit tests
+#[cfg(test)]
+mod test{
+	use super::*;
+    use crate::model::{PhysicsMesh,PhysicsMeshView};
+
+    fn mesh_contains_point(mesh:PhysicsMeshView<'_>,point:Planar64Vec3)->bool{
+		const ENABLE_FAST_FAIL:bool=true;
+		// TODO: remove mesh negation
+		minimum_difference::<ENABLE_FAST_FAIL,_,_>(&mesh,point,
+			// on_exact
+			|is_intersecting,_simplex|{
+				is_intersecting
+			},
+			// on_escape
+			|_simplex|{
+				// intersection is guaranteed at this point
+				true
+			},
+			// fast_fail value
+			||false
+		)
+	}
+
+	#[test]
+	fn test_cube_points(){
+		let mesh=PhysicsMesh::unit_cube();
+		let mesh_view=mesh.complete_mesh_view();
+		assert!(mesh_contains_point(mesh_view,vec3::NEG_Z));
+	}
+}