From 0e6cc64c89a49bcff6746dfe1964d899755778a4 Mon Sep 17 00:00:00 2001
From: Dane Johnson <daneallenjohnson@protonmail.com>
Date: Fri, 15 Apr 2022 13:15:39 -0500
Subject: [PATCH] Camera, impl macro for "Childbearing" (really?)

---
 src/gameobject.rs | 67 ++++++++++++++++++++++++++++++++++-------------
 src/main.rs       |  6 +++--
 2 files changed, 53 insertions(+), 20 deletions(-)

diff --git a/src/gameobject.rs b/src/gameobject.rs
index e5e67c3..40e7396 100644
--- a/src/gameobject.rs
+++ b/src/gameobject.rs
@@ -13,6 +13,30 @@ pub trait Childbearing<T> {
     fn find_node(&mut self, name: &str) -> Option<&mut Box<T>>;
 }
 
+macro_rules! impl_childbearing {
+    ($t:ty, $e:path) => {
+	impl Childbearing<$t> for Node {
+	    fn add_child(&mut self, name: &str, child: $t) {
+		self.children.push(Node::new(name.to_string(), $e(Box::new(child))));
+	    }
+	    fn find_node(&mut self, name: &str) -> Option<&mut Box<$t>> {
+		match self.children.iter_mut().find(|node| node.name == name) {
+		    Some(node) => {
+			if let $e(child) = &mut node.gameobject {
+			    Some(child)
+			} else {
+			    None
+			}
+		    },
+		    None => None,
+		}
+	    }
+	}
+    }
+}
+
+
+
 impl Node {
     pub fn new(name: String, gameobject: GameObject) -> Self {
 	Node {
@@ -25,6 +49,7 @@ impl Node {
 
 pub enum GameObject {
     Null,
+    Camera(Box<Camera>),
     Mesh(Box<Mesh>),
 }
 
@@ -50,6 +75,29 @@ pub trait Spatial {
     fn set_transform(&mut self, transform: Transform);
 }
 
+pub struct Camera {
+    transform: Transform,
+}
+
+impl Camera {
+    pub fn new() -> Self {
+	Camera {
+	    transform: Default::default(),
+	}
+    }
+}
+
+impl Spatial for Camera {
+    fn get_transform(&self) -> Transform {
+	self.transform
+    }
+    fn set_transform(&mut self, transform: Transform) {
+	self.transform = transform
+    }
+}
+
+impl_childbearing!(Camera, GameObject::Camera);
+
 pub struct Mesh {
     pub model: Model,
     transform: Transform,
@@ -73,21 +121,4 @@ impl Spatial for Mesh {
     }
 }
 
-impl Childbearing<Mesh> for Node {
-    fn add_child(&mut self, name: &str, child: Mesh) {
-	self.children.push(Node::new(name.to_string(), GameObject::Mesh(Box::new(child))));
-    }
-    fn find_node(&mut self, name: &str) -> Option<&mut Box<Mesh>> {
-	match self.children.iter_mut().find(|node| node.name == name) {
-	    Some(node) => {
-		if let GameObject::Mesh(mesh) = &mut node.gameobject {
-		    Some(mesh)
-		} else {
-		    None
-		}
-	    },
-	    None => None,
-	}
-    }
-}
-
+impl_childbearing!(Mesh, GameObject::Mesh);
diff --git a/src/main.rs b/src/main.rs
index cd5b9e6..43eadec 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -31,6 +31,7 @@ fn main() {
     let mut device_manager = crate::device::DeviceManager::new();
 
     let mut root = Node::new("_root_".to_string(), GameObject::Null);
+    root.add_child("camera", Camera::new());
     
     let mut cube = Mesh::new(Model::new(&display, "Box.glb"));
     cube.set_transform(gameobject::Transform {
@@ -89,17 +90,18 @@ fn main() {
 		} else if device_manager.is_pressed(&device::Key::D) {
 		    transform.rotation.x -= 1.0 * delta;
 		}
+
 		cube.set_transform(transform);
 		let mvp = glm::perspective::<f32>(4.0/3.0, 45.0_f32.to_radians(), 0.2, 100.0);
 		let mvp = glm::translate::<f32>(&mvp, &cube.get_transform().position);
 		let mvp = glm::rotate_x(&mvp, cube.get_transform().rotation.x);
-
-		
 		
 		let uniforms = uniform! {
 		    MVP: *mvp.as_ref(),
 		};
 		cube.model.draw(&mut target, &program, &uniforms, &params);
+
+		let _camera: &mut Box<Camera> = root.find_node("camera").unwrap();
 		
 		target.finish().unwrap();
 	    }