Fixed rounded corners in Metal

Cocoa/Document.m

@@ -314,6 +314,8 @@ static void printImage(GB_gameboy_t *gb, uint32_t *image, uint8_t height,
     NSMutableParagraphStyle *paragraph_style = [[NSMutableParagraphStyle alloc] init];
     [paragraph_style setLineSpacing:2];
     
+    self.mainWindow.backgroundColor = [NSColor blackColor];
+    
     self.debuggerSideViewInput.font = [NSFont userFixedPitchFontOfSize:12];
     self.debuggerSideViewInput.textColor = [NSColor whiteColor];
     self.debuggerSideViewInput.defaultParagraphStyle = paragraph_style;

Cocoa/Document.xib

@@ -49,18 +49,12 @@
             <view key="contentView" id="gIp-Ho-8D9">
                 <rect key="frame" x="0.0" y="0.0" width="160" height="144"/>
                 <autoresizingMask key="autoresizingMask"/>
-                <subviews>
-                    <customView id="KTk-4M-J7t" customClass="GBBorderView">
-                        <rect key="frame" x="0.0" y="0.0" width="160" height="144"/>
-                        <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                 <subviews>
                     <view id="uqf-pe-VAF" customClass="GBView">
                         <rect key="frame" x="0.0" y="0.0" width="160" height="144"/>
                         <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                     </view>
                 </subviews>
-                    </customView>
-                </subviews>
             </view>
             <connections>
                 <outlet property="delegate" destination="-2" id="jvM-lC-fKb"/>

Cocoa/GBBorderView.h

@@ -1,5 +0,0 @@
-#import <Cocoa/Cocoa.h>
-
-@interface GBBorderView : NSView
-
-@end

Cocoa/GBBorderView.m

@@ -1,11 +0,0 @@
-#import "GBBorderView.h"
-
-@implementation GBBorderView
-
-- (void)drawRect:(NSRect)dirtyRect {
-    [[NSColor blackColor] setFill];
-    NSRectFill(dirtyRect);
-    [super drawRect:dirtyRect];
-}
-
-@end

Cocoa/GBViewMetal.m

@@ -71,6 +71,13 @@ static const vector_float2 rect[] =
     [self loadShader];
 }
 
+- (void)addSubview:(NSView *)view
+{
+    /* Fixes rounded corners */
+    [super addSubview:view];
+    [self setWantsLayer:YES];
+}
+
 - (void) loadShader
 {
     NSError *error = nil;