feat(render): stub some culling code

1 files changed, 47 insertions, 0 deletions

diff --git a/stockton-render/src/culling.rs b/stockton-render/src/culling.rs
new file mode 100644
index 0000000..a9b8753
--- /dev/null
+++ b/stockton-render/src/culling.rs
@@ -0,0 +1,47 @@
+// Copyright (C) 2019 Oscar Shrimpton
+
+// This program is free software: you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the Free
+// Software Foundation, either version 3 of the License, or (at your option)
+// any later version.
+
+// This program is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+// more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Functions for figuring out what to render
+
+use stockton_bsp::BSPFile;
+use stockton_types::Vector3;
+
+/// Get the visible faces according to visdata and frustum culling
+// TODO: Write this. For now, just render all faces
+pub fn get_visible_faces<'a>(pos: Vector3, file: &BSPFile) -> Vec<usize> {
+	let mut visible = Vec::with_capacity(file.faces.faces.len());
+	for x in 0..file.faces.faces.len() {
+		visible.push(x);
+	}
+
+	return visible;
+}
+
+/// Get the viscluster pos lies in 
+fn get_cluster_id(pos: Vector3, file: &BSPFile) -> usize {
+	let mut node = &file.tree.root;
+	while node.leaf.is_none() {
+		let plane = file.planes.planes[node.plane_idx as usize];
+		let dist = plane.normal.dot(&pos) - plane.dist;
+
+		if dist >= 0.0 {
+			node = &node.children.as_ref().unwrap()[0]
+		} else {
+			node = &node.children.as_ref().unwrap()[1]
+		}
+	}
+
+	node.leaf.as_ref().unwrap().cluster_id as usize
+}
\ No newline at end of file