From 9c98502e10f7393bcc4164dbdb7e180a5a3f914f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?H=C3=A9ctor=20Ram=C3=B3n=20Jim=C3=A9nez?=
 <hector0193@gmail.com>
Date: Sun, 19 Apr 2020 21:55:33 +0200
Subject: [PATCH] Fix alignment in triangle pipeline of `iced_wgpu`

---
 wgpu/src/triangle.rs | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/wgpu/src/triangle.rs b/wgpu/src/triangle.rs
index 51a6f954..83d84bc4 100644
--- a/wgpu/src/triangle.rs
+++ b/wgpu/src/triangle.rs
@@ -224,11 +224,9 @@ impl Pipeline {
 
         // We upload everything upfront
         for (origin, mesh) in meshes {
-            let transform = Uniforms {
-                transform: (transformation
-                    * Transformation::translate(origin.x, origin.y))
-                .into(),
-            };
+            let transform = (transformation
+                * Transformation::translate(origin.x, origin.y))
+            .into();
 
             let vertex_buffer = device
                 .create_buffer_mapped(
@@ -357,12 +355,28 @@ impl Pipeline {
 #[derive(Debug, Clone, Copy)]
 struct Uniforms {
     transform: [f32; 16],
+    // We need to align this to 256 bytes to please `wgpu`...
+    // TODO: Be smarter and stop wasting memory!
+    _padding_a: [f32; 32],
+    _padding_b: [f32; 16],
 }
 
 impl Default for Uniforms {
     fn default() -> Self {
         Self {
             transform: *Transformation::identity().as_ref(),
+            _padding_a: [0.0; 32],
+            _padding_b: [0.0; 16],
+        }
+    }
+}
+
+impl From<Transformation> for Uniforms {
+    fn from(transformation: Transformation) -> Uniforms {
+        Self {
+            transform: transformation.into(),
+            _padding_a: [0.0; 32],
+            _padding_b: [0.0; 16],
         }
     }
 }