add color changing

crates/shaders-shared/src/lib.rs

@@ -1,6 +1,6 @@
 #![cfg_attr(target_arch = "spirv", no_std)]
 
-use glam::Mat4;
+use glam::{Mat4, Vec3};
 
 #[repr(C)]
 #[derive(Clone)]
@@ -8,4 +8,5 @@ pub struct UniformBufferObject {
     pub model: Mat4,
     pub view: Mat4,
     pub proj: Mat4,
+    pub model_color: Vec3,
 }