From 89c5564133145230d0d93165c10f99cc8b2a6f94 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Markus=20Ginth=C3=B6r?= <markus.ginthoer@gmx.at>
Date: Fri, 12 Apr 2019 17:44:44 +0200
Subject: [PATCH] Configure Swapchain with supported composite_alpha

---
 wgpu-native/src/device.rs | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/wgpu-native/src/device.rs b/wgpu-native/src/device.rs
index e0e19dfb7..7528ff813 100644
--- a/wgpu-native/src/device.rs
+++ b/wgpu-native/src/device.rs
@@ -1534,7 +1534,7 @@ pub fn device_create_swap_chain(
     let mut surface_guard = HUB.surfaces.write();
     let surface = &mut surface_guard[surface_id];
 
-    let (caps, formats, _present_modes, _composite_alphas) = {
+    let (caps, formats, _present_modes, composite_alphas) = {
         let adapter_guard = HUB.adapters.read();
         let adapter = &adapter_guard[device.adapter_id];
         assert!(surface
@@ -1544,12 +1544,13 @@ pub fn device_create_swap_chain(
     };
     let num_frames = caps.image_count.start; //TODO: configure?
     let usage = conv::map_texture_usage(desc.usage, hal::format::Aspects::COLOR);
-    let config = hal::SwapchainConfig::new(
+    let mut config = hal::SwapchainConfig::new(
         desc.width,
         desc.height,
         conv::map_texture_format(desc.format),
         num_frames, //TODO: configure?
     );
+    config.composite_alpha = *composite_alphas.iter().next().unwrap();
 
     if let Some(formats) = formats {
         assert!(