From b2b892ae56a8cac1e4800661d7f652139b17be41 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?furby=E2=84=A2?= <devs@wabi.foundation>
Date: Fri, 14 Feb 2025 15:46:38 -0700
Subject: [PATCH] add visionOS metal implementation for usdview.
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: furby™ <devs@wabi.foundation>
---
 Sources/UsdView/Hydra/Hydra+RenderEngine.swift   | 13 +++++++++++--
 Sources/UsdView/Hydra/Hydra+View.swift           | 16 ++++++++--------
 .../UsdView/Hydra/MTL/Hydra+MTLRenderer.swift    |  8 ++++----
 Sources/UsdView/Hydra/MTL/Hydra+UI+MTLView.swift |  2 +-
 4 files changed, 24 insertions(+), 15 deletions(-)

diff --git a/Sources/UsdView/Hydra/Hydra+RenderEngine.swift b/Sources/UsdView/Hydra/Hydra+RenderEngine.swift
index 80dfb1bb9..9fe191cd6 100644
--- a/Sources/UsdView/Hydra/Hydra+RenderEngine.swift
+++ b/Sources/UsdView/Hydra/Hydra+RenderEngine.swift
@@ -13,10 +13,10 @@
 import Foundation
 import PixarUSD
 
-#if canImport(Metal) && !os(visionOS)
+#if canImport(Metal)
   import Metal
   import MetalKit
-#endif // canImport(Metal) && !os(visionOS)
+#endif // canImport(Metal)
 
 public enum Hydra
 {
@@ -24,7 +24,10 @@ public enum Hydra
   {
     public var stage: UsdStageRefPtr
 
+#if canImport(Metal)
     private let hgi: Pixar.HgiMetalPtr
+#endif // canImport(Metal)
+
     private let engine: UsdImagingGL.EngineSharedPtr
     private var viewCamera: Hydra.Camera
 
@@ -38,8 +41,12 @@ public enum Hydra
     {
       self.stage = stage
 
+#if canImport(Metal)
       hgi = HgiMetal.createHgi()
       let driver = HdDriver(name: .renderDriver, driver: hgi.value)
+#else // !canImport(Metal)
+      let driver = HdDriver()
+#endif // canImport(Metal)
 
       engine = UsdImagingGL.Engine.createEngine(
         rootPath: stage.getPseudoRoot().getPath(),
@@ -224,6 +231,7 @@ public enum Hydra
       return frustum
     }
 
+#if canImport(Metal)
     public var hydraDevice: MTLDevice
     {
       hgi.device
@@ -233,6 +241,7 @@ public enum Hydra
     {
       hgi
     }
+#endif // canImport(Metal)
 
     public func getEngine() -> UsdImagingGL.EngineSharedPtr
     {
diff --git a/Sources/UsdView/Hydra/Hydra+View.swift b/Sources/UsdView/Hydra/Hydra+View.swift
index 7a7897aed..71b5d1c0a 100644
--- a/Sources/UsdView/Hydra/Hydra+View.swift
+++ b/Sources/UsdView/Hydra/Hydra+View.swift
@@ -13,29 +13,29 @@
 import Foundation
 import PixarUSD
 
-#if canImport(Metal) && !os(visionOS)
+#if canImport(Metal)
   import Metal
   import MetalKit
-#endif // canImport(Metal) && !os(visionOS)
+#endif // canImport(Metal)
 
 public extension Hydra
 {
-  #if os(macOS) || os(iOS)
+  #if os(macOS) || os(iOS) || os(visionOS)
     typealias Viewport = Hydra.MTLView
-  #elseif os(visionOS) || os(tvOS) || os(watchOS)
+  #elseif os(tvOS) || os(watchOS)
     typealias Viewport = UIViewRepresentable
   #else
     struct Viewport {}
-  #endif // canImport(Metal) && !os(visionOS)
+  #endif // os(macOS) || os(iOS) || os(visionOS)
 }
 
 public extension Hydra.Viewport
 {
   init(engine: Hydra.RenderEngine)
   {
-    #if canImport(Metal) && !os(visionOS)
-      let renderer = Hydra.MTLRenderer(device: engine.hydraDevice, hydra: engine)
+    #if canImport(Metal)
+      let renderer = Hydra.MTLRenderer(hydra: engine)
       self.init(hydra: engine, renderer: renderer)
-    #endif // canImport(Metal) && !os(visionOS)
+    #endif // canImport(Metal)
   }
 }
diff --git a/Sources/UsdView/Hydra/MTL/Hydra+MTLRenderer.swift b/Sources/UsdView/Hydra/MTL/Hydra+MTLRenderer.swift
index 3e663ce9f..73551af5d 100644
--- a/Sources/UsdView/Hydra/MTL/Hydra+MTLRenderer.swift
+++ b/Sources/UsdView/Hydra/MTL/Hydra+MTLRenderer.swift
@@ -12,7 +12,7 @@
 
 import Foundation
 import PixarUSD
-#if canImport(Metal) && !os(visionOS)
+#if canImport(Metal)
   import Metal
   import MetalKit
 
@@ -26,9 +26,9 @@ import PixarUSD
 
       private var inFlightSemaphore = DispatchSemaphore(value: 1)
 
-      convenience init(device: MTLDevice, hydra: Hydra.RenderEngine)
+      convenience init(hydra: Hydra.RenderEngine)
       {
-        self.init(device: device)!
+        self.init(device: hydra.hydraDevice)!
         self.hydra = hydra
       }
 
@@ -181,4 +181,4 @@ import PixarUSD
       }
     }
   }
-#endif // canImport(Metal) && !os(visionOS)
+#endif // canImport(Metal)
diff --git a/Sources/UsdView/Hydra/MTL/Hydra+UI+MTLView.swift b/Sources/UsdView/Hydra/MTL/Hydra+UI+MTLView.swift
index 25f87d799..543f3a304 100644
--- a/Sources/UsdView/Hydra/MTL/Hydra+UI+MTLView.swift
+++ b/Sources/UsdView/Hydra/MTL/Hydra+UI+MTLView.swift
@@ -17,7 +17,7 @@ import PixarUSD
   import Combine
   import SwiftUI
 
-  #if os(iOS)
+  #if os(iOS) || os(visionOS)
     import Metal
     import MetalKit