From 720fd5f4e12aec478b059758bd4ff3cbf4a28a3c Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Fri, 29 Sep 2023 16:27:13 +0200
Subject: [PATCH] Try other adapters, if one fails to return device

---
 crates/fj-viewer/src/graphics/device.rs   | 43 ++++++++++++++++++++++-
 crates/fj-viewer/src/graphics/renderer.rs | 26 ++++++++++++--
 2 files changed, 65 insertions(+), 4 deletions(-)

diff --git a/crates/fj-viewer/src/graphics/device.rs b/crates/fj-viewer/src/graphics/device.rs
index 73b35f053..63d3bee21 100644
--- a/crates/fj-viewer/src/graphics/device.rs
+++ b/crates/fj-viewer/src/graphics/device.rs
@@ -1,4 +1,4 @@
-use tracing::debug;
+use tracing::{debug, error};
 
 #[derive(Debug)]
 pub struct Device {
@@ -27,6 +27,43 @@ impl Device {
         Ok((device, adapter, features))
     }
 
+    pub async fn try_from_all_adapters(
+        instance: &wgpu::Instance,
+    ) -> Result<(Self, wgpu::Adapter, wgpu::Features), DeviceError> {
+        let mut all_adapters =
+            instance.enumerate_adapters(wgpu::Backends::all());
+
+        let result = loop {
+            let Some(adapter) = all_adapters.next() else {
+                debug!("No more adapters to try");
+                break None;
+            };
+
+            let (device, features) = match Device::new(&adapter).await {
+                Ok((device, adapter)) => (device, adapter),
+                Err(err) => {
+                    error!(
+                        "Failed to get device from adapter {:?}: {:?}",
+                        adapter.get_info(),
+                        err,
+                    );
+                    continue;
+                }
+            };
+
+            break Some((device, adapter, features));
+        };
+
+        for adapter in all_adapters {
+            debug!(
+                "Remaining adapter that wasn't tried: {:?}",
+                adapter.get_info()
+            );
+        }
+
+        result.ok_or(DeviceError::FoundNoWorkingAdapter)
+    }
+
     pub async fn new(
         adapter: &wgpu::Adapter,
     ) -> Result<(Self, wgpu::Features), DeviceError> {
@@ -82,4 +119,8 @@ pub enum DeviceError {
     /// Failed to request device
     #[error("Failed to request device")]
     RequestDevice(#[from] wgpu::RequestDeviceError),
+
+    /// Found no working adapter to get a device from
+    #[error("Found no working adapter to get a device from")]
+    FoundNoWorkingAdapter,
 }
diff --git a/crates/fj-viewer/src/graphics/renderer.rs b/crates/fj-viewer/src/graphics/renderer.rs
index 424017ad1..6f3960db7 100644
--- a/crates/fj-viewer/src/graphics/renderer.rs
+++ b/crates/fj-viewer/src/graphics/renderer.rs
@@ -1,7 +1,7 @@
 use std::{io, mem::size_of, vec};
 
 use thiserror::Error;
-use tracing::{debug, trace};
+use tracing::{debug, error, trace};
 use wgpu::util::DeviceExt as _;
 
 use crate::{
@@ -50,8 +50,28 @@ impl Renderer {
             debug!("Available adapter: {:?}", adapter.get_info());
         }
 
-        let (device, adapter, features) =
-            Device::from_preferred_adapter(&instance, &surface).await?;
+        let result = Device::from_preferred_adapter(&instance, &surface).await;
+        let (device, adapter, features) = match result {
+            Ok((device, adapter, features)) => (device, adapter, features),
+            Err(_) => {
+                error!("Failed to acquire device from preferred adapter");
+
+                match Device::try_from_all_adapters(&instance).await {
+                    Ok((device, adapter, features)) => {
+                        (device, adapter, features)
+                    }
+                    Err(err) => {
+                        error!("Prepend `RUST_LOG=fj_viewer=debug` and re-run");
+                        error!("Then open an issue and post your output");
+                        error!(
+                            "https://github.com/hannobraun/fornjot/issues/new"
+                        );
+
+                        return Err(err.into());
+                    }
+                }
+            }
+        };
 
         let color_format = 'color_format: {
             let capabilities = surface.get_capabilities(&adapter);