From 5b4f54a19ed72c0e5a734ff81b9dc8a4835b7a6b Mon Sep 17 00:00:00 2001
From: griffi-gh <prasol258@gmail.com>
Date: Fri, 27 Jan 2023 22:01:51 +0100
Subject: [PATCH] wip culling

---
 shaders/world.frag    |  5 +++++
 src/camera/frustum.rs |  2 +-
 src/world/render.rs   | 14 ++++----------
 3 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/shaders/world.frag b/shaders/world.frag
index e07b5e1..017c5e1 100644
--- a/shaders/world.frag
+++ b/shaders/world.frag
@@ -5,6 +5,7 @@ in vec2 v_uv;
 flat in uint v_tex_index;
 out vec4 color;
 uniform sampler2DArray tex;
+uniform bool debug;
 
 void main() {
   // base color from texture
@@ -12,4 +13,8 @@ void main() {
   //basic "lighting"
   float light = abs(v_normal.x) + .8 * abs(v_normal.y) + .6 * abs(v_normal.z);
   color *= vec4(vec3(light), 1.);
+  //highlight
+  if (debug) {
+    color *= vec4(1., 0., 0., 1.);
+  }
 }
diff --git a/src/camera/frustum.rs b/src/camera/frustum.rs
index 259b211..78f97c6 100644
--- a/src/camera/frustum.rs
+++ b/src/camera/frustum.rs
@@ -79,7 +79,7 @@ impl Frustum {
   }
 
   //this may be broken
-  pub fn intersect_box(&self, minp: Vec3, maxp: Vec3) -> bool {
+  pub fn is_box_visible(&self, minp: Vec3, maxp: Vec3) -> bool {
     // check box outside/inside of frustum
     for i in 0..PLANE_COUNT {
       if self.planes[i].dot(vec4(minp.x, minp.y, minp.z, 1.)) < 0. &&
diff --git a/src/world/render.rs b/src/world/render.rs
index ec1460b..99ad9ad 100644
--- a/src/world/render.rs
+++ b/src/world/render.rs
@@ -69,22 +69,15 @@ pub fn draw_world(
   });
   let view = camera.view_matrix.to_cols_array_2d();
   let perspective = camera.perspective_matrix.to_cols_array_2d();
-  let camera_mat = camera.perspective_matrix * camera.view_matrix;
 
   for (&position, chunk) in &chunks.chunks {
     if let Some(key) = chunk.mesh_index {
       let mesh = meshes.get(key).expect("Mesh index pointing to nothing");
-      let world_position = position.as_vec3a() * CHUNK_SIZE as f32;
+      let world_position = position.as_vec3() * CHUNK_SIZE as f32;
       if mesh.index_buffer.len() == 0 {
         continue
       }
-
-      //basic culling
-      // let chunk_center = world_position + Vec3A::splat(CHUNK_SIZE as f32) * 0.5;
-      // let cull_point = camera_mat * chunk_center.extend(1.);
-      // if (cull_point.xyz() / cull_point.w).abs().cmpgt(Vec3::splat(1.)).any() {
-      //   continue
-      // }
+      let debug = !camera.frustum.is_box_visible(world_position, world_position + Vec3::splat(CHUNK_SIZE as f32));
 
       target.0.draw(
         &mesh.vertex_buffer,
@@ -94,7 +87,8 @@ pub fn draw_world(
           position_offset: world_position.to_array(),
           view: view,
           perspective: perspective,
-          tex: texture_sampler
+          tex: texture_sampler,
+          debug: debug
         },
         &draw_parameters
       ).unwrap();