From 9f7246efba4fc8289e04554f63b2c1653e1e5330 Mon Sep 17 00:00:00 2001
From: Jared Roberts <jaredr@gmail.com>
Date: Thu, 15 Sep 2016 00:21:13 -0700
Subject: [PATCH] depth testing

---
 src/bin/gl.rs | 11 ++++++++---
 src/vr.rs     | 29 ++++++++++++++++-------------
 2 files changed, 24 insertions(+), 16 deletions(-)

diff --git a/src/bin/gl.rs b/src/bin/gl.rs
index 1db408d..75a278d 100644
--- a/src/bin/gl.rs
+++ b/src/bin/gl.rs
@@ -17,7 +17,7 @@ use num_traits::identities::One;
 use piston_window::{PistonWindow, Window, WindowSettings};
 
 pub type ColorFormat = gfx::format::Srgba8;
-//pub type DepthFormat = gfx::format::DepthStencil;
+pub type DepthFormat = gfx::format::DepthStencil;
 
 const NEAR: f32 = 0.01;
 const FAR: f32 = 1000.0;
@@ -36,6 +36,7 @@ gfx_defines!{
         vbuf: gfx::VertexBuffer<Vertex> = (),
         trans: gfx::ConstantBuffer<Trans> = "b_trans",
         pixcolor: gfx::RenderTarget<ColorFormat> = "pixcolor",
+        depth: gfx::DepthTarget<DepthFormat> = gfx::preset::depth::LESS_EQUAL_WRITE,
     }
 }
 
@@ -63,9 +64,9 @@ fn main() {
                                                     pipe::new())
         .expect("create pipeline");
 
-    let (tex_left, tgt_left) = vr::create_eyebuffer(&mut window.factory, render_size)
+    let (tex_left, tgt_left, depth_left) = vr::create_eyebuffer(&mut window.factory, render_size)
         .expect("create left renderbuffer");
-    let (tex_right, tgt_right) = vr::create_eyebuffer(&mut window.factory, render_size)
+    let (tex_right, tgt_right, depth_right) = vr::create_eyebuffer(&mut window.factory, render_size)
         .expect("create right renderbuffer");
     let (vertex_buffer, slice) = window.factory.create_vertex_buffer_with_slice(&POLYGON, POLYGON_IDX);
 
@@ -73,16 +74,19 @@ fn main() {
         vbuf: vertex_buffer.clone(),
         trans: window.factory.create_constant_buffer(1),
         pixcolor: window.output_color.clone(),
+        depth: window.output_stencil.clone(),
     };
     let pipe_left = pipe::Data {
         vbuf: vertex_buffer.clone(),
         trans: window.factory.create_constant_buffer(1),
         pixcolor: tgt_left,
+        depth: depth_left,
     };
     let pipe_right = pipe::Data {
         vbuf: vertex_buffer.clone(),
         trans: window.factory.create_constant_buffer(1),
         pixcolor: tgt_right,
+        depth: depth_right,
     };
     window.encoder.update_constant_buffer(
         &pipe_monitor.trans,
@@ -128,6 +132,7 @@ fn main() {
             .into_iter() {
                 info!("\tpass for eye: {:?}", pass.0);
                 window.encoder.clear(&pass.1.pixcolor, [0.1, 0.2, 0.3, 1.0]);
+                window.encoder.clear_depth(&pass.1.depth, 1.0);
 
                 // Submit eye textures
                 if let Some((eye, tex)) = pass.0 {
diff --git a/src/vr.rs b/src/vr.rs
index f24e607..1ed6dd4 100644
--- a/src/vr.rs
+++ b/src/vr.rs
@@ -5,10 +5,11 @@ extern crate num_traits;
 extern crate openvr as vr;
 extern crate openvr_sys;
 
-use self::gfx::{tex, Factory, Typed};
-
 pub use self::vr::Eye;
 pub use self::vr::tracking::TrackedDeviceClass;
+
+use self::gfx::{tex, Factory, Typed};
+use self::gfx_device_gl::Resources as GLResources;
 use self::na::Inverse;
 use self::num_traits::identities::Zero;
 use self::num_traits::identities::One;
@@ -16,7 +17,7 @@ use self::num_traits::identities::One;
 pub struct VR {
     system: vr::IVRSystem,
     compositor: vr::IVRCompositor,
-    gfx_handles: gfx::handle::Manager<gfx_device_gl::Resources>,
+    gfx_handles: gfx::handle::Manager<GLResources>,
 }
 
 impl VR {
@@ -33,7 +34,7 @@ impl VR {
         self.compositor.wait_get_poses()
     }
 
-    pub fn submit<T>(&mut self, eye: Eye, tex: &gfx::handle::Texture<gfx_device_gl::Resources, T>) {
+    pub fn submit<T>(&mut self, eye: Eye, tex: &gfx::handle::Texture<GLResources, T>) {
         let tex_id = match self.gfx_handles.ref_texture(tex.raw()) {
             &gfx_device_gl::NewTexture::Surface(id) => id,
             _ => panic!("Not a surface")
@@ -86,14 +87,14 @@ impl<N: Copy> AsMatrix4<N> for [[N; 4]; 4] {
     }
 }
 
-pub fn create_eyebuffer<T>(factory: &mut gfx_device_gl::Factory,
-                           size: vr::common::Size)
-                           -> Result<(gfx::handle::Texture<gfx_device_gl::Resources,
-                                                           T::Surface>,
-                                      gfx::handle::RenderTargetView<gfx_device_gl::Resources,
-                                                                    T>),
-                                     gfx::CombinedError>
-    where T: gfx::format::RenderFormat + gfx::format::TextureFormat {
+pub fn create_eyebuffer<T, D>(factory: &mut gfx_device_gl::Factory,
+                              size: vr::common::Size)
+                              -> Result<(gfx::handle::Texture<GLResources, T::Surface>,
+                                         gfx::handle::RenderTargetView<GLResources, T>,
+                                         gfx::handle::DepthStencilView<GLResources, D>),
+                                        gfx::CombinedError>
+    where T: gfx::format::RenderFormat + gfx::format::TextureFormat,
+          D: gfx::format::DepthFormat + gfx::format::TextureFormat {
     let tex = try!(factory.create_texture(
         tex::Kind::D2(size.width as tex::Size, size.height as tex::Size, tex::AaMode::Single),
         1, // levels
@@ -101,5 +102,7 @@ pub fn create_eyebuffer<T>(factory: &mut gfx_device_gl::Factory,
         gfx::Usage::GpuOnly, // Usage
         Some(<T::Channel as gfx::format::ChannelTyped>::get_channel_type()))); // hint: format::ChannelType?
     let tgt = try!(factory.view_texture_as_render_target(&tex, 0, None));
-    Ok((tex, tgt))
+    let depth = try!(factory.create_depth_stencil_view_only(size.width as tex::Size,
+                                                            size.height as tex::Size));
+    Ok((tex, tgt, depth))
 }