From a4b500ff4b02165fdccd6d90c652f083c7114d4b Mon Sep 17 00:00:00 2001
From: Svenn-Arne Dragly <dragly@cognite.com>
Date: Mon, 8 Jul 2019 10:36:25 +0200
Subject: [PATCH] [rs] Make opengl_to_wgpu_matrix into a constant

---
 wgpu/examples/cube/main.rs   |  2 +-
 wgpu/examples/framework.rs   | 16 ++++++++--------
 wgpu/examples/mipmap/main.rs |  2 +-
 wgpu/examples/shadow/main.rs |  4 ++--
 4 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/wgpu/examples/cube/main.rs b/wgpu/examples/cube/main.rs
index dbb25e468d..b5544deb73 100644
--- a/wgpu/examples/cube/main.rs
+++ b/wgpu/examples/cube/main.rs
@@ -100,7 +100,7 @@ impl Example {
             cgmath::Point3::new(0f32, 0.0, 0.0),
             cgmath::Vector3::unit_z(),
         );
-        let mx_correction = framework::opengl_to_wgpu_matrix();
+        let mx_correction = framework::OPENGL_TO_WGPU_MATRIX;
         mx_correction * mx_projection * mx_view
     }
 }
diff --git a/wgpu/examples/framework.rs b/wgpu/examples/framework.rs
index 424da2ab92..40ea24f663 100644
--- a/wgpu/examples/framework.rs
+++ b/wgpu/examples/framework.rs
@@ -1,5 +1,13 @@
 use log::info;
 
+#[cfg_attr(rustfmt, rustfmt_skip)]
+pub const OPENGL_TO_WGPU_MATRIX: cgmath::Matrix4<f32> = cgmath::Matrix4::new(
+    1.0, 0.0, 0.0, 0.0,
+    0.0, -1.0, 0.0, 0.0,
+    0.0, 0.0, 0.5, 0.0,
+    0.0, 0.0, 0.5, 1.0,
+);
+
 #[allow(dead_code)]
 pub fn cast_slice<T>(data: &[T]) -> &[u8] {
     use std::mem::size_of;
@@ -30,14 +38,6 @@ pub fn load_glsl(code: &str, stage: ShaderStage) -> Vec<u8> {
     spv
 }
 
-pub fn opengl_to_wgpu_matrix() -> cgmath::Matrix4<f32> {
-    // converts from -1,1 Z to 0,1 Z and flips Y
-    cgmath::Matrix4::new(1.0, 0.0, 0.0, 0.0,
-                         0.0, -1.0, 0.0, 0.0,
-                         0.0, 0.0, 0.5, 0.0,
-                         0.0, 0.0, 0.5, 1.0)
-}
-
 pub trait Example {
     fn init(sc_desc: &wgpu::SwapChainDescriptor, device: &mut wgpu::Device) -> Self;
     fn resize(&mut self, sc_desc: &wgpu::SwapChainDescriptor, device: &mut wgpu::Device);
diff --git a/wgpu/examples/mipmap/main.rs b/wgpu/examples/mipmap/main.rs
index f6c39c7466..7194f2d231 100644
--- a/wgpu/examples/mipmap/main.rs
+++ b/wgpu/examples/mipmap/main.rs
@@ -64,7 +64,7 @@ impl Example {
             cgmath::Point3::new(0f32, 50.0, 0.0),
             cgmath::Vector3::unit_z(),
         );
-        let mx_correction = framework::opengl_to_wgpu_matrix();
+        let mx_correction = framework::OPENGL_TO_WGPU_MATRIX;
         mx_correction * mx_projection * mx_view
     }
 
diff --git a/wgpu/examples/shadow/main.rs b/wgpu/examples/shadow/main.rs
index 8a4cc86a4a..e57af3ea49 100644
--- a/wgpu/examples/shadow/main.rs
+++ b/wgpu/examples/shadow/main.rs
@@ -113,7 +113,7 @@ impl Light {
             near: self.depth.start,
             far: self.depth.end,
         };
-        let mx_correction = framework::opengl_to_wgpu_matrix();
+        let mx_correction = framework::OPENGL_TO_WGPU_MATRIX;
         let mx_view_proj = mx_correction * cgmath::Matrix4::from(projection.to_perspective()) * mx_view;
         LightRaw {
             proj: *mx_view_proj.as_ref(),
@@ -175,7 +175,7 @@ impl Example {
             cgmath::Point3::new(0f32, 0.0, 0.0),
             cgmath::Vector3::unit_z(),
         );
-        let mx_correction = framework::opengl_to_wgpu_matrix();
+        let mx_correction = framework::OPENGL_TO_WGPU_MATRIX;
         mx_correction * mx_projection * mx_view
     }
 }