high-level API for ConvexMesh, TriangleMesh, HeightField (#195)

* high-level API for ConvexMesh, TriangleMesh, HeightField

---------

Co-authored-by: Tom Solberg <[email protected]>

Author: rlidwka

physx/src/convex_mesh.rs

@@ -1,6 +1,27 @@
-use crate::{owner::Owner, traits::Class};
+use std::mem::MaybeUninit;
 
-use physx_sys::PxConvexMesh_release_mut;
+use crate::{
+    math::{PxBounds3, PxVec3},
+    owner::Owner,
+    traits::Class,
+};
+
+use physx_sys::{
+    PxConvexMesh_getIndexBuffer,
+    PxConvexMesh_getLocalBounds,
+    PxConvexMesh_getMassInformation,
+    PxConvexMesh_getNbPolygons,
+    PxConvexMesh_getNbVertices,
+    PxConvexMesh_getPolygonData,
+    PxConvexMesh_getVertices,
+    // TODO: SDF getters
+    //PxConvexMesh_getSDF,
+    //PxConvexMesh_getConcreteTypeName,
+    PxConvexMesh_isGpuCompatible,
+    PxConvexMesh_release_mut,
+    // TODO: high level wrapper for PxMassProperties
+    PxMassProperties,
+};
 
 #[repr(transparent)]
 pub struct ConvexMesh {
@@ -18,6 +39,90 @@ impl ConvexMesh {
     pub unsafe fn from_raw(ptr: *mut physx_sys::PxConvexMesh) -> Option<Owner<ConvexMesh>> {
         unsafe { Owner::from_raw(ptr as *mut Self) }
     }
+
+    /// Returns the number of vertices.
+    pub fn get_nb_vertices(&self) -> u32 {
+        unsafe { PxConvexMesh_getNbVertices(self.as_ptr()) }
+    }
+
+    /// Returns the vertices.
+    pub fn get_vertices(&self) -> &[PxVec3] {
+        unsafe {
+            std::slice::from_raw_parts(
+                PxConvexMesh_getVertices(self.as_ptr()) as *const PxVec3,
+                self.get_nb_vertices() as usize,
+            )
+        }
+    }
+
+    /// Returns the index buffer.
+    pub fn get_index_buffer(&self) -> &[u8] {
+        let polygon_count = self.get_nb_polygons();
+
+        // for each polygon index buffer contains its points,
+        // so we take last polygon's index offset plus its length to calculate total size
+        let index_buffer_length = if polygon_count > 0 {
+            let last_polygon = self.get_polygon_data(polygon_count - 1).unwrap();
+            last_polygon.index_base as usize + last_polygon.nb_verts as usize
+        } else {
+            0
+        };
+
+        unsafe {
+            std::slice::from_raw_parts(
+                PxConvexMesh_getIndexBuffer(self.as_ptr()),
+                index_buffer_length,
+            )
+        }
+    }
+
+    /// Returns the number of polygons.
+    pub fn get_nb_polygons(&self) -> u32 {
+        unsafe { PxConvexMesh_getNbPolygons(self.as_ptr()) }
+    }
+
+    /// Returns the polygon data.
+    pub fn get_polygon_data(&self, index: u32) -> Option<HullPolygon> {
+        let mut polygon = MaybeUninit::uninit();
+
+        if unsafe { PxConvexMesh_getPolygonData(self.as_ptr(), index, polygon.as_mut_ptr()) } {
+            Some(unsafe { polygon.assume_init() }.into())
+        } else {
+            None
+        }
+    }
+
+    /// Returns the mass properties of the mesh assuming unit density.
+    pub fn get_mass_information(&self) -> PxMassProperties {
+        let mut mass = MaybeUninit::uninit();
+        let mut local_inertia = MaybeUninit::uninit();
+        let mut local_center_of_mass = MaybeUninit::uninit();
+
+        unsafe {
+            PxConvexMesh_getMassInformation(
+                self.as_ptr(),
+                mass.as_mut_ptr(),
+                local_inertia.as_mut_ptr(),
+                local_center_of_mass.as_mut_ptr(),
+            );
+
+            PxMassProperties {
+                inertiaTensor: local_inertia.assume_init(),
+                centerOfMass: local_center_of_mass.assume_init(),
+                mass: mass.assume_init(),
+            }
+        }
+    }
+
+    /// Returns the local-space (vertex space) AABB from the convex mesh.
+    pub fn get_local_bounds(&self) -> PxBounds3 {
+        unsafe { PxConvexMesh_getLocalBounds(self.as_ptr()) }.into()
+    }
+
+    /// This method decides whether a convex mesh is gpu compatible.
+    pub fn is_gpu_compatible(&self) -> bool {
+        unsafe { PxConvexMesh_isGpuCompatible(self.as_ptr()) }
+    }
 }
 
 unsafe impl Send for ConvexMesh {}
@@ -28,3 +133,33 @@ impl Drop for ConvexMesh {
         unsafe { PxConvexMesh_release_mut(self.as_mut_ptr()) }
     }
 }
+
+#[derive(Debug, Clone)]
+pub struct HullPolygon {
+    /// Plane equation for this polygon.
+    pub plane: [f32; 4],
+    /// Number of vertices/edges in the polygon.
+    pub nb_verts: u16,
+    /// Offset in index buffer.
+    pub index_base: u16,
+}
+
+impl From<physx_sys::PxHullPolygon> for HullPolygon {
+    fn from(value: physx_sys::PxHullPolygon) -> Self {
+        Self {
+            plane: value.mPlane,
+            nb_verts: value.mNbVerts,
+            index_base: value.mIndexBase,
+        }
+    }
+}
+
+impl From<HullPolygon> for physx_sys::PxHullPolygon {
+    fn from(value: HullPolygon) -> Self {
+        Self {
+            mPlane: value.plane,
+            mNbVerts: value.nb_verts,
+            mIndexBase: value.index_base,
+        }
+    }
+}