hal/vk: Refactor create_surface_from_ns_view , make it both correct…

… on iOS macOS
gfx-rs · Feb 19, 2022 · 8dd711e · 8dd711e
1 parent fa35c0a
commit 8dd711e
Showing 1 changed file with 28 additions and 22 deletions.
diff --git a/wgpu-hal/src/vulkan/instance.rs b/wgpu-hal/src/vulkan/instance.rs
@@ -368,7 +368,7 @@ impl super::Instance {
     }
 
     #[cfg(any(target_os = "macos", target_os = "ios"))]
-    fn create_surface_from_ns_view(&self, view: *mut c_void) -> super::Surface {
+    fn create_surface_from_view(&self, view: *mut c_void) -> super::Surface {
         use core_graphics_types::{base::CGFloat, geometry::CGRect};
         use objc::{
             class, msg_send,
@@ -381,27 +381,33 @@ impl super::Instance {
             let existing: *mut Object = msg_send![view, layer];
             let class = class!(CAMetalLayer);
 
-            let use_current = if existing.is_null() {
-                false
-            } else {
-                let result: BOOL = msg_send![existing, isKindOfClass: class];
-                result == YES
-            };
-
-            if use_current {
+            let use_current: BOOL = msg_send![existing, isKindOfClass: class];
+            if use_current == YES {
                 existing
             } else {
-                let layer: *mut Object = msg_send![class, new];
-                let () = msg_send![view, setLayer: layer];
-                let bounds: CGRect = msg_send![view, bounds];
-                let () = msg_send![layer, setBounds: bounds];
-
-                let window: *mut Object = msg_send![view, window];
-                if !window.is_null() {
-                    let scale_factor: CGFloat = msg_send![window, backingScaleFactor];
-                    let () = msg_send![layer, setContentsScale: scale_factor];
-                }
-                layer
+                let new_layer: *mut Object = msg_send![class, new];
+                let frame: CGRect = msg_send![existing, bounds];
+                let () = msg_send![new_layer, setFrame: frame];
+
+                let scale_factor: CGFloat = if cfg!(target_os = "ios") {
+                    let () = msg_send![existing, addSublayer: new_layer];
+                    // On iOS, `create_surface_from_view` may be called before the application initialization is complete,
+                    // `msg_send![view, window]` and `msg_send![window, screen]` will get null.
+                    let screen: *mut Object = msg_send![class!(UIScreen), mainScreen];
+                    msg_send![screen, nativeScale]
+                } else {
+                    let () = msg_send![view, setLayer: new_layer];
+                    let () = msg_send![view, setWantsLayer: YES];
+                    let window: *mut Object = msg_send![view, window];
+                    if !window.is_null() {
+                        msg_send![window, backingScaleFactor]
+                    } else {
+                        1.0
+                    }
+                };
+                let () = msg_send![new_layer, setContentsScale: scale_factor];
+
+                new_layer
             }
         };
 
@@ -586,13 +592,13 @@ impl crate::Instance<super::Api> for super::Instance {
             RawWindowHandle::AppKit(handle)
                 if self.extensions.contains(&ext::MetalSurface::name()) =>
             {
-                Ok(self.create_surface_from_ns_view(handle.ns_view))
+                Ok(self.create_surface_from_view(handle.ns_view))
             }
             #[cfg(target_os = "ios")]
             RawWindowHandle::UiKit(handle)
                 if self.extensions.contains(&ext::MetalSurface::name()) =>
             {
-                Ok(self.create_surface_from_ns_view(handle.ui_view))
+                Ok(self.create_surface_from_view(handle.ui_view))
             }
             _ => Err(crate::InstanceError),
         }