fix text draw functions

Fix drawAttributedStringGL and drawAttributedStringMTL for 10.15 and 11 since initWithFocusedViewRect was deprecated starting with 10.15 and was not working anymore.
Checked the new code is also working on 10.14.

Author: Waitsnake

AnimatedGif/AnimatedGifView.m

@@ -1623,12 +1623,13 @@ - (void) drawAttributedStringGL:(NSAttributedString *)attributedString atPoint:(
     NSSize frameSize = NSMakeSize(0.0f, 0.0f);
 
     frameSize = [attributedString size];
-    NSImage * image = [[NSImage alloc] initWithSize:frameSize];
-    [image lockFocus];
-    [[NSGraphicsContext currentContext] setShouldAntialias:YES];
+    NSBitmapImageRep *bitmap = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:NULL pixelsWide:round(frameSize.width) pixelsHigh:round(frameSize.height)
+        bitsPerSample:8 samplesPerPixel:4 hasAlpha:YES isPlanar:NO colorSpaceName:NSCalibratedRGBColorSpace bitmapFormat:NS32BitLittleEndianBitmapFormat bytesPerRow:round(frameSize.width)*4 bitsPerPixel:0];
+    NSGraphicsContext *context = [NSGraphicsContext graphicsContextWithBitmapImageRep:bitmap];
+    [NSGraphicsContext saveGraphicsState];
+    [NSGraphicsContext setCurrentContext:context];
     [attributedString drawAtPoint:NSMakePoint (0.0f, 0.0f)];
-    NSBitmapImageRep *bitmap = [[NSBitmapImageRep alloc] initWithFocusedViewRect:NSMakeRect(0.0f, 0.0f, frameSize.width, frameSize.height)];
-    [image unlockFocus];
+    [NSGraphicsContext restoreGraphicsState];
     texturSize.width = [bitmap pixelsWide];
     texturSize.height = [bitmap pixelsHigh];
     NSRect bounds = NSMakeRect (point.x, point.y, texturSize.width, texturSize.height);
@@ -1874,12 +1875,13 @@ - (void) drawAttributedStringMTL:(NSAttributedString *)attributedString atPoint:
     NSSize frameSize = NSMakeSize(0.0f, 0.0f);
 
     frameSize = [attributedString size];
-    NSImage * image = [[NSImage alloc] initWithSize:frameSize];
-    [image lockFocus];
-    [[NSGraphicsContext currentContext] setShouldAntialias:YES];
+    NSBitmapImageRep *bitmap = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:NULL pixelsWide:round(frameSize.width) pixelsHigh:round(frameSize.height)
+        bitsPerSample:8 samplesPerPixel:4 hasAlpha:YES isPlanar:NO colorSpaceName:NSCalibratedRGBColorSpace bitmapFormat:NS32BitLittleEndianBitmapFormat bytesPerRow:round(frameSize.width)*4 bitsPerPixel:0];
+    NSGraphicsContext *context = [NSGraphicsContext graphicsContextWithBitmapImageRep:bitmap];
+    [NSGraphicsContext saveGraphicsState];
+    [NSGraphicsContext setCurrentContext:context];
     [attributedString drawAtPoint:NSMakePoint (0.0f, 0.0f)];
-    NSBitmapImageRep *bitmap = [[NSBitmapImageRep alloc] initWithFocusedViewRect:NSMakeRect(0.0f, 0.0f, frameSize.width, frameSize.height)];
-    [image unlockFocus];
+    [NSGraphicsContext restoreGraphicsState];
     texturSize.width = [bitmap pixelsWide];
     texturSize.height = [bitmap pixelsHigh];
     NSRect bounds = NSMakeRect (point.x, point.y, texturSize.width, texturSize.height);