1 files changed, 140 insertions, 0 deletions

diff --git a/contrib/SDL-3.2.8/src/video/uikit/SDL_uikitmetalview.m b/contrib/SDL-3.2.8/src/video/uikit/SDL_uikitmetalview.m
new file mode 100644
index 0000000..010dae4
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+++ b/contrib/SDL-3.2.8/src/video/uikit/SDL_uikitmetalview.m
@@ -0,0 +1,140 @@
+/*
+ Simple DirectMedia Layer
+ Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+
+ This software is provided 'as-is', without any express or implied
+ warranty.  In no event will the authors be held liable for any damages
+ arising from the use of this software.
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute it
+ freely, subject to the following restrictions:
+
+ 1. The origin of this software must not be misrepresented; you must not
+ claim that you wrote the original software. If you use this software
+ in a product, an acknowledgment in the product documentation would be
+ appreciated but is not required.
+ 2. Altered source versions must be plainly marked as such, and must not be
+ misrepresented as being the original software.
+ 3. This notice may not be removed or altered from any source distribution.
+ */
+
+/*
+ * @author Mark Callow, www.edgewise-consulting.com.
+ *
+ * Thanks to @slime73 on GitHub for their gist showing how to add a CAMetalLayer
+ * backed view.
+ */
+
+#include "SDL_internal.h"
+
+#if defined(SDL_VIDEO_DRIVER_UIKIT) && (defined(SDL_VIDEO_VULKAN) || defined(SDL_VIDEO_METAL))
+
+#include "../SDL_sysvideo.h"
+#include "../../events/SDL_windowevents_c.h"
+
+#import "SDL_uikitwindow.h"
+#import "SDL_uikitmetalview.h"
+
+@implementation SDL_uikitmetalview
+
+// Returns a Metal-compatible layer.
++ (Class)layerClass
+{
+    return [CAMetalLayer class];
+}
+
+- (instancetype)initWithFrame:(CGRect)frame
+                        scale:(CGFloat)scale
+{
+    if ((self = [super initWithFrame:frame])) {
+        self.tag = SDL_METALVIEW_TAG;
+        self.layer.contentsScale = scale;
+        [self updateDrawableSize];
+    }
+
+    return self;
+}
+
+// Set the size of the metal drawables when the view is resized.
+- (void)layoutSubviews
+{
+    [super layoutSubviews];
+    [self updateDrawableSize];
+}
+
+- (void)updateDrawableSize
+{
+    CGSize size = self.bounds.size;
+    size.width *= self.layer.contentsScale;
+    size.height *= self.layer.contentsScale;
+
+    CAMetalLayer *metallayer = ((CAMetalLayer *)self.layer);
+    if (metallayer.drawableSize.width != size.width ||
+        metallayer.drawableSize.height != size.height) {
+        metallayer.drawableSize = size;
+        SDL_SendWindowEvent([self getSDLWindow], SDL_EVENT_WINDOW_METAL_VIEW_RESIZED, 0, 0);
+    }
+}
+
+@end
+
+SDL_MetalView UIKit_Metal_CreateView(SDL_VideoDevice *_this, SDL_Window *window)
+{
+    @autoreleasepool {
+        SDL_UIKitWindowData *data = (__bridge SDL_UIKitWindowData *)window->internal;
+        CGFloat scale = 1.0;
+        SDL_uikitmetalview *metalview;
+
+        if (window->flags & SDL_WINDOW_HIGH_PIXEL_DENSITY) {
+            /* Set the scale to the natural scale factor of the screen - then
+             * the backing dimensions of the Metal view will match the pixel
+             * dimensions of the screen rather than the dimensions in points
+             * yielding high resolution on retine displays.
+             */
+#ifndef SDL_PLATFORM_VISIONOS
+            scale = data.uiwindow.screen.nativeScale;
+#else
+            // VisionOS doesn't use the concept of "nativeScale" like other iOS devices.
+            // We use a fixed scale factor of 2.0 to achieve better pixel density.
+            // This is because VisionOS presents a virtual 1280x720 "screen", but we need
+            // to render at a higher resolution for optimal visual quality.
+            // TODO: Consider making this configurable or determining it dynamically
+            // based on the specific visionOS device capabilities.
+            scale = 2.0;
+#endif
+        }
+
+        metalview = [[SDL_uikitmetalview alloc] initWithFrame:data.uiwindow.bounds
+                                                        scale:scale];
+        if (metalview == nil) {
+            SDL_OutOfMemory();
+            return NULL;
+        }
+
+        [metalview setSDLWindow:window];
+
+        return (void *)CFBridgingRetain(metalview);
+    }
+}
+
+void UIKit_Metal_DestroyView(SDL_VideoDevice *_this, SDL_MetalView view)
+{
+    @autoreleasepool {
+        SDL_uikitmetalview *metalview = CFBridgingRelease(view);
+
+        if ([metalview isKindOfClass:[SDL_uikitmetalview class]]) {
+            [metalview setSDLWindow:NULL];
+        }
+    }
+}
+
+void *UIKit_Metal_GetLayer(SDL_VideoDevice *_this, SDL_MetalView view)
+{
+    @autoreleasepool {
+        SDL_uikitview *uiview = (__bridge SDL_uikitview *)view;
+        return (__bridge void *)uiview.layer;
+    }
+}
+
+#endif // SDL_VIDEO_DRIVER_UIKIT && (SDL_VIDEO_VULKAN || SDL_VIDEO_METAL)