feat: some stuff

packages/utils/Cargo.toml

@@ -12,3 +12,4 @@ serde = { version = "1.0", features = ["derive"] }
 serde_json = { version = "1.0", default-features = false, features = ["alloc"] }
 console_error_panic_hook = { version = "0.1.7", optional = true }
 gl_matrix = "0.0.2"
+glam = "0.27.0"

packages/utils/src/geometry/calculate_normals.rs

@@ -0,0 +1,50 @@
+use crate::{decode_float, encode_float};
+use glam::Vec3;
+
+pub fn calculate_normals(geometry: &mut [i32]) {
+    let vertex_count = geometry[1] as usize;
+    let face_count = geometry[2] as usize;
+    let index_start = 3;
+    let indices_end = index_start + face_count * 3;
+    let positions_start = indices_end;
+    let positions_end = positions_start + vertex_count * 3;
+    let normals_start = positions_end;
+
+    let mut last_normal = Vec3::ZERO;
+
+    for i in 0..face_count {
+        let base_idx1 = geometry[index_start + i * 3] as usize * 3;
+        let base_idx2 = geometry[index_start + i * 3 + 1] as usize * 3;
+        let base_idx3 = geometry[index_start + i * 3 + 2] as usize * 3;
+
+        let v1 = Vec3::new(
+            decode_float(geometry[positions_start + base_idx1]),
+            decode_float(geometry[positions_start + base_idx1 + 1]),
+            decode_float(geometry[positions_start + base_idx1 + 2]),
+        );
+        let v2 = Vec3::new(
+            decode_float(geometry[positions_start + base_idx2]) - v1.x,
+            decode_float(geometry[positions_start + base_idx2 + 1]) - v1.y,
+            decode_float(geometry[positions_start + base_idx2 + 2]) - v1.z,
+        );
+        let v3 = Vec3::new(
+            decode_float(geometry[positions_start + base_idx3]) - v1.x,
+            decode_float(geometry[positions_start + base_idx3 + 1]) - v1.y,
+            decode_float(geometry[positions_start + base_idx3 + 2]) - v1.z,
+        );
+
+        let mut normal = v2.cross(v3).normalize();
+        if normal.length_squared() == 0.0 {
+            normal = last_normal;
+        } else {
+            last_normal = normal;
+        }
+
+        for j in 0..3 {
+            let idx = geometry[index_start + i * 3 + j] as usize * 3;
+            geometry[normals_start + idx] = encode_float(normal.x);
+            geometry[normals_start + idx + 1] = encode_float(normal.y);
+            geometry[normals_start + idx + 2] = encode_float(normal.z);
+        }
+    }
+}

packages/utils/src/geometry/extrude_path.rs

@@ -1,2 +1 @@
 pub fn extrude_path(path: &[i32]) {}
-

packages/utils/src/geometry/mod.rs

@@ -0,0 +1,3 @@
+pub mod calculate_normals;
+pub mod extrude_path;
+

packages/utils/src/lib.rs

@@ -5,6 +5,7 @@ mod tree;
 pub use encoding::*;
 pub use helpers::*;
 pub use tree::*;
+pub mod geometry;
 
 pub fn set_panic_hook() {
     // When the `console_error_panic_hook` feature is enabled, we can call the