Move Material to new module && TriangleBVH intersect && Seperate light and material

ray-tracing-material/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "ray-tracing-material"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+rand = "0.8.5"
+ray-tracing-core = { path = "../ray-tracing-core" }

ray-tracing-material/src/default.rs

@@ -0,0 +1,11 @@
+use rand::Rng;
+use ray_tracing_core::prelude::*;
+
+pub struct DefaultMaterial {}
+
+impl<R: Rng> Material<R> for DefaultMaterial {
+    // evaluates the bsdf
+    fn eval(&self, _w_in: Dir3, _w_out: Dir3, _rng: &mut R) -> Color {
+        Color::black()
+    }
+}

ray-tracing-material/src/diffuse.rs

@@ -0,0 +1,20 @@
+use rand::Rng;
+use ray_tracing_core::prelude::*;
+
+pub struct DiffuseMaterial {
+    pub(crate) albedo: Color,
+}
+
+impl DiffuseMaterial {
+    pub fn new(color: Color) -> Self {
+        Self {
+            albedo: color * FloatConsts::FRAC_1_PI,
+        }
+    }
+}
+
+impl<R: Rng> Material<R> for DiffuseMaterial {
+    fn eval(&self, _w_in: Dir3, _w_out: Dir3, _rng: &mut R) -> Color {
+        self.albedo
+    }
+}

ray-tracing-material/src/lib.rs

@@ -0,0 +1,2 @@
+pub mod default;
+pub mod diffuse;