1 files changed, 182 insertions, 0 deletions

diff --git a/contrib/SDL-3.2.8/src/video/cocoa/SDL_cocoametalview.m b/contrib/SDL-3.2.8/src/video/cocoa/SDL_cocoametalview.m
new file mode 100644
index 0000000..af84e93
--- /dev/null
+++ b/contrib/SDL-3.2.8/src/video/cocoa/SDL_cocoametalview.m
@@ -0,0 +1,182 @@
+/*
+  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"
+
+#include "../../events/SDL_windowevents_c.h"
+
+#import "SDL_cocoametalview.h"
+
+#if defined(SDL_VIDEO_DRIVER_COCOA) && (defined(SDL_VIDEO_VULKAN) || defined(SDL_VIDEO_METAL))
+
+static bool SDLCALL SDL_MetalViewEventWatch(void *userdata, SDL_Event *event)
+{
+    /* Update the drawable size when SDL receives a size changed event for
+     * the window that contains the metal view. It would be nice to use
+     * - (void)resizeWithOldSuperviewSize:(NSSize)oldSize and
+     * - (void)viewDidChangeBackingProperties instead, but SDL's size change
+     * events don't always happen in the same frame (for example when a
+     * resizable window exits a fullscreen Space via the user pressing the OS
+     * exit-space button). */
+    if (event->type == SDL_EVENT_WINDOW_PIXEL_SIZE_CHANGED) {
+        @autoreleasepool {
+            SDL3_cocoametalview *view = (__bridge SDL3_cocoametalview *)userdata;
+            if (view.sdlWindowID == event->window.windowID) {
+                [view updateDrawableSize];
+            }
+        }
+    }
+    return false;
+}
+
+@implementation SDL3_cocoametalview
+
+// Return a Metal-compatible layer.
++ (Class)layerClass
+{
+    return NSClassFromString(@"CAMetalLayer");
+}
+
+// Indicate the view wants to draw using a backing layer instead of drawRect.
+- (BOOL)wantsUpdateLayer
+{
+    return YES;
+}
+
+/* When the wantsLayer property is set to YES, this method will be invoked to
+ * return a layer instance.
+ */
+- (CALayer *)makeBackingLayer
+{
+    return [self.class.layerClass layer];
+}
+
+- (instancetype)initWithFrame:(NSRect)frame
+                      highDPI:(BOOL)highDPI
+                     windowID:(Uint32)windowID
+                       opaque:(BOOL)opaque
+{
+    self = [super initWithFrame:frame];
+    if (self != nil) {
+        self.highDPI = highDPI;
+        self.sdlWindowID = windowID;
+        self.wantsLayer = YES;
+
+        // Allow resize.
+        self.autoresizingMask = NSViewWidthSizable | NSViewHeightSizable;
+
+        self.layer.opaque = opaque;
+
+        SDL_AddWindowEventWatch(SDL_WINDOW_EVENT_WATCH_EARLY, SDL_MetalViewEventWatch, (__bridge void *)(self));
+
+        [self updateDrawableSize];
+    }
+
+    return self;
+}
+
+- (void)dealloc
+{
+    SDL_RemoveWindowEventWatch(SDL_WINDOW_EVENT_WATCH_EARLY, SDL_MetalViewEventWatch, (__bridge void *)(self));
+}
+
+- (NSInteger)tag
+{
+    return SDL_METALVIEW_TAG;
+}
+
+- (void)updateDrawableSize
+{
+    CAMetalLayer *metalLayer = (CAMetalLayer *)self.layer;
+    NSSize size = self.bounds.size;
+    NSSize backingSize = size;
+
+    if (self.highDPI) {
+        /* Note: NSHighResolutionCapable must be set to true in the app's
+         * Info.plist in order for the backing size to be high res.
+         */
+        backingSize = [self convertSizeToBacking:size];
+    }
+
+    metalLayer.contentsScale = backingSize.height / size.height;
+    metalLayer.drawableSize = NSSizeToCGSize(backingSize);
+}
+
+- (NSView *)hitTest:(NSPoint)point
+{
+    return nil;
+}
+
+@end
+
+SDL_MetalView Cocoa_Metal_CreateView(SDL_VideoDevice *_this, SDL_Window *window)
+{
+    @autoreleasepool {
+        SDL_CocoaWindowData *data = (__bridge SDL_CocoaWindowData *)window->internal;
+        NSView *view = data.nswindow.contentView;
+        BOOL highDPI = (window->flags & SDL_WINDOW_HIGH_PIXEL_DENSITY) != 0;
+        BOOL opaque = (window->flags & SDL_WINDOW_TRANSPARENT) == 0;
+        Uint32 windowID = SDL_GetWindowID(window);
+        SDL3_cocoametalview *newview;
+        SDL_MetalView metalview;
+
+        newview = [[SDL3_cocoametalview alloc] initWithFrame:view.frame
+                                                    highDPI:highDPI
+                                                   windowID:windowID
+                                                     opaque:opaque];
+        if (newview == nil) {
+            SDL_OutOfMemory();
+            return NULL;
+        }
+
+        [view addSubview:newview];
+
+        // Make sure the drawable size is up to date after attaching the view.
+        [newview updateDrawableSize];
+
+        metalview = (SDL_MetalView)CFBridgingRetain(newview);
+
+        return metalview;
+    }
+}
+
+void Cocoa_Metal_DestroyView(SDL_VideoDevice *_this, SDL_MetalView view)
+{
+    @autoreleasepool {
+        SDL3_cocoametalview *metalview = CFBridgingRelease(view);
+        [metalview removeFromSuperview];
+    }
+}
+
+void *Cocoa_Metal_GetLayer(SDL_VideoDevice *_this, SDL_MetalView view)
+{
+    @autoreleasepool {
+        SDL3_cocoametalview *cocoaview = (__bridge SDL3_cocoametalview *)view;
+        return (__bridge void *)cocoaview.layer;
+    }
+}
+
+#endif // SDL_VIDEO_DRIVER_COCOA && (SDL_VIDEO_VULKAN || SDL_VIDEO_METAL)