better to use a struct for the raw mesh data

src/geometry.rs

@@ -1,5 +1,6 @@
 use bytemuck::{Pod, Zeroable};
 use nalgebra::Vector4;
+use rapier3d::parry::math::Point;
 
 #[repr(C)]
 #[derive(Clone, Copy, Debug)]
@@ -10,14 +11,14 @@ pub struct Vertex {
 }
 
 impl Vertex {
-    pub fn position(&self) -> Vector4<f32> {
-        Vector4::new(self.pos[0], self.pos[1], self.pos[2], self.pos[3])
+    pub fn position(&self) -> Point<f32> {
+        Point::<f32>::new(self.pos[0], self.pos[1], self.pos[2])
     }
     pub fn from(pos: [f32; 3], nor: [f32; 3], uv: [f32; 2]) -> Vertex {
         Vertex {
             pos: [pos[0], pos[1], pos[2], 1.0],
             normal: [nor[0], nor[1], nor[2], 0.0],
-            uv: [0.0, 0.0],
+            uv: [uv[0], uv[1]],
         }
     }
 }
@@ -27,31 +28,35 @@ unsafe impl Zeroable for Vertex {}
 
 #[derive(Clone, Debug)]
 pub struct RawMesh {
-    vertices: Vec<Vertex>,
-    normals: Vec<[u32; 3]>,
+    pub vertices: Vec<Vertex>,
+    pub indices: Vec<[u32; 3]>,
 }
 
-pub fn load_obj(obj_path: &str, mtl_path: Option<&str>) -> (Vec<Vertex>, Vec<u32>) {
+pub fn load_obj(obj_path: &str) -> RawMesh {
 
     let (models, materials) = tobj::load_obj(obj_path, true).expect("Failed to load file");
 
     println!("# of models: {}", models.len());
     println!("# of materials: {}", materials.len());
 
+    println!("{:?}", materials);
 
-    let mut index_data: Vec<u32> = Vec::new();
+    let mut index_data: Vec<[u32; 3]> = Vec::new();
     let mut vertex_data = Vec::new();
 
     for model in models {
         let mesh = &model.mesh;
+
+        // Cycle through the faces and chunk out the indices
         let mut next_face = 0;
         for f in 0..mesh.num_face_indices.len() {
+            // calculate the next chunk
             let end = next_face + mesh.num_face_indices[f] as usize;
             let face_indices: Vec<_> = mesh.indices[next_face..end].iter().collect();
 
-            for i in face_indices {
-                index_data.push(*i);
-            }
+            assert!(face_indices.len() == 3, "we only handle triangulated faces");
+            index_data.push([*face_indices[0], *face_indices[1], *face_indices[2]]);
+
             next_face = end;
         }
 
@@ -80,5 +85,8 @@ pub fn load_obj(obj_path: &str, mtl_path: Option<&str>) -> (Vec<Vertex>, Vec<u32
             ));
         }
     }
-    (vertex_data.to_vec(), index_data.to_vec())
+    RawMesh {
+        vertices: vertex_data.to_vec(),
+        indices: index_data.to_vec(),
+    }
 }