Add support for macOS 10.14 Mojave.

MacOS apps running under 10.14 AND linked with SDK 10.14 use a completely different way
to draw to the screen in comparison with the same app running under 10.13 or earlier:
all views are "layer-backed".
This commit makes FLTK apps running under 10.14 and linked with SDK 10.14 explicitly 
use layers to draw to the screen.
FLTK apps remain downward compatible with earlier macOS versions.

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.4@13071 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

1 files changed, 288 insertions, 100 deletions

diff --git a/src/Fl_cocoa.mm b/src/Fl_cocoa.mm
index 68eaf7168..7a64ff64d 100644
--- a/src/Fl_cocoa.mm
+++ b/src/Fl_cocoa.mm
@@ -102,6 +102,7 @@ static int main_screen_height; // height of menubar-containing screen used to co
 static BOOL through_drawRect = NO; 
 // through_Fl_X_flush = YES means Fl_Cocoa_Window_Driver::flush() was called
 static BOOL through_Fl_X_flush = NO;
+static BOOL views_use_CA = NO; // YES means views are layer-backed, as on macOS 10.14 when linked with SDK 10.14
 static int im_enabled = -1;
 // OS version-dependent pasteboard type names
 #if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_6
@@ -529,6 +530,75 @@ void Fl_Cocoa_Screen_Driver::breakMacEventLoop()
 #endif
 @end
 
+@interface FLView : NSView <NSTextInput
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
+, NSTextInputClient
+#endif
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+,NSDraggingSource
+#endif
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_12
+, CALayerDelegate
+#endif
+> {
+  BOOL in_key_event; // YES means keypress is being processed by handleEvent
+  BOOL need_handle; // YES means Fl::handle(FL_KEYBOARD,) is needed after handleEvent processing
+  NSInteger identifier;
+  NSRange selectedRange;
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+@public
+  CGContextRef layer_gc;
+#endif
+}
++ (void)prepareEtext:(NSString*)aString;
++ (void)concatEtext:(NSString*)aString;
+- (BOOL)process_keydown:(NSEvent*)theEvent;
+- (id)initWithFrame:(NSRect)frameRect;
+- (void)drawRect:(NSRect)rect;
+- (BOOL)acceptsFirstResponder;
+- (BOOL)acceptsFirstMouse:(NSEvent*)theEvent;
+- (void)resetCursorRects;
+- (BOOL)performKeyEquivalent:(NSEvent*)theEvent;
+- (void)mouseUp:(NSEvent *)theEvent;
+- (void)rightMouseUp:(NSEvent *)theEvent;
+- (void)otherMouseUp:(NSEvent *)theEvent;
+- (void)mouseDown:(NSEvent *)theEvent;
+- (void)rightMouseDown:(NSEvent *)theEvent;
+- (void)otherMouseDown:(NSEvent *)theEvent;
+- (void)mouseMoved:(NSEvent *)theEvent;
+- (void)mouseDragged:(NSEvent *)theEvent;
+- (void)rightMouseDragged:(NSEvent *)theEvent;
+- (void)otherMouseDragged:(NSEvent *)theEvent;
+- (void)scrollWheel:(NSEvent *)theEvent;
+- (void)magnifyWithEvent:(NSEvent *)theEvent;
+- (void)keyDown:(NSEvent *)theEvent;
+- (void)keyUp:(NSEvent *)theEvent;
+- (void)flagsChanged:(NSEvent *)theEvent;
+- (NSDragOperation)draggingEntered:(id < NSDraggingInfo >)sender;
+- (NSDragOperation)draggingUpdated:(id < NSDraggingInfo >)sender;
+- (BOOL)performDragOperation:(id <NSDraggingInfo>)sender;
+- (void)draggingExited:(id < NSDraggingInfo >)sender;
+- (NSDragOperation)draggingSourceOperationMaskForLocal:(BOOL)isLocal;
+#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_5
+- (void)insertText:(id)aString replacementRange:(NSRange)replacementRange;
+- (void)setMarkedText:(id)aString selectedRange:(NSRange)newSelection replacementRange:(NSRange)replacementRange;
+- (NSAttributedString *)attributedSubstringForProposedRange:(NSRange)aRange actualRange:(NSRangePointer)actualRange;
+- (NSRect)firstRectForCharacterRange:(NSRange)aRange actualRange:(NSRangePointer)actualRange;
+- (NSInteger)windowLevel;
+#endif
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+- (NSDragOperation)draggingSession:(NSDraggingSession *)session sourceOperationMaskForDraggingContext:(NSDraggingContext)context;
+#endif
+- (BOOL)did_view_resolution_change;
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+- (BOOL)wantsLayer;
+- (BOOL)wantsUpdateLayer;
+- (void)updateLayer;
+- (void)viewFrameDidChange;
+#endif
+@end
+
+
 @implementation FLWindow
 - (void)close
 {
@@ -737,9 +807,9 @@ double Fl_Cocoa_Screen_Driver::wait(double time_to_wait)
     // the idle function may turn off idle, we can then wait:
     if (Fl::idle) time_to_wait = 0.0;
   }
-  NSDisableScreenUpdates(); // 10.3 Makes updates to all windows appear as a single event
+  if (fl_mac_os_version < 101100) NSDisableScreenUpdates(); // 10.3 Makes updates to all windows appear as a single event
   Fl::flush();
-  NSEnableScreenUpdates(); // 10.3
+  if (fl_mac_os_version < 101100) NSEnableScreenUpdates(); // 10.3
   if (Fl::idle && !in_idle) // 'idle' may have been set within flush()
     time_to_wait = 0.0;
   int retval = do_queued_events(time_to_wait);
@@ -1078,6 +1148,9 @@ static FLTextView *fltextview_instance = nil;
 - (void)windowDidMiniaturize:(NSNotification *)notif;
 - (BOOL)windowShouldClose:(id)fl;
 - (void)anyWindowWillClose:(NSNotification *)notif;
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+- (void)viewFrameDidChangeNotification:(NSNotification *)notif;
+#endif
 - (void)doNothing:(id)unused;
 @end
 
@@ -1181,6 +1254,18 @@ static FLWindowDelegate *flwindowdelegate_instance = nil;
   // FLTK sets position of parent and children. setSubwindowFrame is no longer necessary.
   if (fl_mac_os_version < 101000) [nsw recursivelySendToSubwindows:@selector(setSubwindowFrame)];
   [nsw checkSubwindowFrame];
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+  if (views_use_CA && [(FLView*)[nsw contentView] did_view_resolution_change]) {
+    if (window->as_gl_window()) { // move layered GL window to different resolution
+      NSView *view = [nsw contentView];
+      [view display]; [view display]; // 2 necessary for toplevel GL windows
+    } else [(FLView*)[nsw contentView] viewFrameDidChange];
+    if (window->parent()) {
+      [nsw setSubwindowFrame];
+      [[nsw contentView] display];
+    }
+  }
+#endif
   fl_unlock_function();
 }
 - (void)windowDidResize:(NSNotification *)notif
@@ -1209,6 +1294,12 @@ static FLWindowDelegate *flwindowdelegate_instance = nil;
   [nsw recursivelySendToSubwindows:@selector(setSubwindowFrame)];
   [nsw recursivelySendToSubwindows:@selector(checkSubwindowFrame)];
   if (window->as_gl_window() && Fl_X::i(window)) d->in_windowDidResize(false);
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+  if (views_use_CA && window->as_gl_window() && !window->parent()) { // resize toplevel layered GL window
+    id pre = [[[nsw contentView] layer] presentationLayer];
+    if (pre) [[nsw contentView] layer].contents = pre;
+   }
+#endif
   fl_unlock_function();
 }
 - (void)windowDidResignKey:(NSNotification *)notif
@@ -1323,6 +1414,13 @@ static FLWindowDelegate *flwindowdelegate_instance = nil;
   }
   fl_unlock_function();
 }
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+-(void)viewFrameDidChangeNotification:(NSNotification *)notif
+{
+  NSView *view = (NSView*)[notif object];
+  if ([view layer] && [view isMemberOfClass:[FLView class]]) [(FLView*)view viewFrameDidChange];
+}
+#endif
 - (void)doNothing:(id)unused
 {
   return;
@@ -1666,6 +1764,12 @@ void Fl_Cocoa_Screen_Driver::open_display_platform() {
 					     selector:@selector(anyWindowWillClose:) 
 						 name:NSWindowWillCloseNotification 
 					       object:nil];
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+    [[NSNotificationCenter defaultCenter] addObserver:[FLWindowDelegate singleInstance]
+                                             selector:@selector(viewFrameDidChangeNotification:)
+                                                 name:NSViewFrameDidChangeNotification
+                                               object:nil];
+#endif
     if (![NSThread isMultiThreaded]) {
       // With old OS X versions, it is necessary to create one thread for secondary pthreads to be
       // allowed to use cocoa, especially to create an NSAutoreleasePool.
@@ -2067,61 +2171,144 @@ static FLTextInputContext* fltextinputcontext_instance = nil;
 }
 @end
 
-@interface FLView : NSView <NSTextInput
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-, NSTextInputClient
-#endif
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
-,NSDraggingSource
-#endif
-> {
-  BOOL in_key_event; // YES means keypress is being processed by handleEvent
-  BOOL need_handle; // YES means Fl::handle(FL_KEYBOARD,) is needed after handleEvent processing
-  NSInteger identifier;
-  NSRange selectedRange;
+/* Implementation note for the support of layer-backed views.
+ MacOS 10.14 Mojave changes the way all drawing to displays is performed:
+ all NSView objects become layer-backed, that is, the drawing is done by
+ Core Animation to a CALayer object whose content is then displayed by the NSView.
+ The global variable views_use_CA is set to YES when such change applies,
+ that is, for apps running under 10.14 and linked to SDK 10.14.
+ When views_use_CA is NO, views are not supposed to be layer-backed.
+ 
+ Each layer-backed non-OpenGL window has a single FLView object which itself has an associated CALayer.
+ FLView sets wantsUpdateLayer to YES. Consequently, FLView objects are drawn
+ by the updateLayer message. An FLView has also a member variable
+ CGContextRef layer_gc, a bitmap context the size of the view (double on Retina).
+ All Quartz drawings go to this bitmap. updateLayer finishes by using an image copy
+ of the bitmap as the layer's contents. That step fills the window.
+ FLView implements viewFrameDidChange which deletes the bitmap and zeros layer_gc.
+ This ensures the bitmap is recreated when the window is resized.
+ viewFrameDidChange is also called when the window flips between low/high resolution displays.
+ 
+ Each layer-backed OpenGL window has an associated FLViewGL object, derived from FLView.
+ FLViewGL sets wantsUpdateLayer to NO. Consequently, FLViewGL objects are drawn
+ by the drawLayer:inContext: message which calls drawRect: which draws the GL scene.
+ */
+
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+static CGContextRef prepare_bitmap_for_layer(int w, int h ) {
+  CGColorSpaceRef cspace = CGColorSpaceCreateDeviceRGB();
+  CGContextRef gc = CGBitmapContextCreate(NULL,  w,  h, 8, 4 * w, cspace, kCGImageAlphaPremultipliedFirst);
+  CGColorSpaceRelease(cspace);
+  CGContextClearRect(gc, CGRectMake(0,0,w,h));
+  return gc;
 }
-+ (void)prepareEtext:(NSString*)aString;
-+ (void)concatEtext:(NSString*)aString;
-- (BOOL)process_keydown:(NSEvent*)theEvent;
-- (id)initWithFrame:(NSRect)frameRect;
-- (void)drawRect:(NSRect)rect;
-- (BOOL)acceptsFirstResponder;
-- (BOOL)acceptsFirstMouse:(NSEvent*)theEvent;
-- (void)resetCursorRects;
-- (BOOL)performKeyEquivalent:(NSEvent*)theEvent;
-- (void)mouseUp:(NSEvent *)theEvent;
-- (void)rightMouseUp:(NSEvent *)theEvent;
-- (void)otherMouseUp:(NSEvent *)theEvent;
-- (void)mouseDown:(NSEvent *)theEvent;
-- (void)rightMouseDown:(NSEvent *)theEvent;
-- (void)otherMouseDown:(NSEvent *)theEvent;
-- (void)mouseMoved:(NSEvent *)theEvent;
-- (void)mouseDragged:(NSEvent *)theEvent;
-- (void)rightMouseDragged:(NSEvent *)theEvent;
-- (void)otherMouseDragged:(NSEvent *)theEvent;
-- (void)scrollWheel:(NSEvent *)theEvent;
-- (void)magnifyWithEvent:(NSEvent *)theEvent;
-- (void)keyDown:(NSEvent *)theEvent;
-- (void)keyUp:(NSEvent *)theEvent;
-- (void)flagsChanged:(NSEvent *)theEvent;
-- (NSDragOperation)draggingEntered:(id < NSDraggingInfo >)sender;
-- (NSDragOperation)draggingUpdated:(id < NSDraggingInfo >)sender;
-- (BOOL)performDragOperation:(id <NSDraggingInfo>)sender;
-- (void)draggingExited:(id < NSDraggingInfo >)sender;
-- (NSDragOperation)draggingSourceOperationMaskForLocal:(BOOL)isLocal;
-#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_5
-- (void)insertText:(id)aString replacementRange:(NSRange)replacementRange;
-- (void)setMarkedText:(id)aString selectedRange:(NSRange)newSelection replacementRange:(NSRange)replacementRange;
-- (NSAttributedString *)attributedSubstringForProposedRange:(NSRange)aRange actualRange:(NSRangePointer)actualRange;
-- (NSRect)firstRectForCharacterRange:(NSRange)aRange actualRange:(NSRangePointer)actualRange;
-- (NSInteger)windowLevel;
-#endif
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
-- (NSDragOperation)draggingSession:(NSDraggingSession *)session sourceOperationMaskForDraggingContext:(NSDraggingContext)context;
-#endif
+
+@interface FLViewGL : FLView // only for layered GL windows
+- (BOOL)wantsUpdateLayer;
+- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx;
+- (void)viewFrameDidChange;
 @end
 
+@implementation FLViewGL
+- (BOOL)wantsUpdateLayer {
+  return NO;
+}
+- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx {
+  [self drawRect:[self frame]];//essai
+  Fl_Window *window = [(FLWindow*)[self window] getFl_Window];
+  if (window->parent()) window->redraw(); // useful during resize of GL subwindow
+  if (Fl_Cocoa_Window_Driver::driver(window)->wait_for_expose_value) {
+    // 1st drawing of GL window
+    NSRect r = [[self window] frame];
+    r.size.width -= 1;
+    [[self window] setFrame:r display:NO]; // very dirty but works. Should find something better.
+    r.size.width += 1;
+    [[self window] setFrame:r display:YES];    
+     }
+  Fl_Cocoa_Window_Driver::driver(window)->wait_for_expose_value = 0;
+}
+- (void)viewFrameDidChange
+{
+    [[self layer] display]; // for layered GL windows
+}
+@end
+#endif //>= MAC_OS_X_VERSION_10_8
+
 @implementation FLView
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+- (BOOL)wantsLayer {
+  return views_use_CA;
+}
+- (BOOL)wantsUpdateLayer {
+  return views_use_CA;
+}
+- (void)updateLayer {
+  // called if views are layered (but not for GL) : all drawing to window goes through this
+  Fl_Window *window = [(FLWindow*)[self window] getFl_Window];
+  Fl_Cocoa_Window_Driver *d = Fl_Cocoa_Window_Driver::driver(window);
+  float scale = Fl::screen_driver()->scale(0);
+  NSRect rect = [self frame];
+  if (!window->parent() && window->border() && fabs(rect.size.height - window->h() * scale) > 5. ) { // this happens with tabbed windows
+    window->resize([[self window] frame].origin.x/scale,
+                   (main_screen_height - ([[self window] frame].origin.y + rect.size.height))/scale,
+                   rect.size.width/scale, rect.size.height/scale);
+  }
+  if (!layer_gc) { // runs when window is created, resized, changed screen resolution
+    NSRect r = [self frame];
+    [self layer].bounds = NSRectToCGRect(r);
+    d->wait_for_expose_value = 0;
+    [self did_view_resolution_change];
+    if (d->mapped_to_retina()) {
+      r.size.width *= 2; r.size.height *= 2;
+      [self layer].contentsScale = 2.;
+    } else [self layer].contentsScale = 1.;
+    layer_gc = prepare_bitmap_for_layer(r.size.width, r.size.height);
+    Fl_X *i = Fl_X::i(window);
+    if ( i->region ) {
+      Fl_Graphics_Driver::default_driver().XDestroyRegion(i->region);
+      i->region = 0;
+    }
+    window->clear_damage(FL_DAMAGE_ALL);
+  }
+  if (window->damage()) {
+    through_drawRect = YES;
+    d->Fl_Window_Driver::flush();
+    Fl_Cocoa_Window_Driver::q_release_context();
+    through_drawRect = NO;
+    window->clear_damage();
+    CGImageRef cgimg = CGBitmapContextCreateImage(layer_gc);  // requires 10.4
+    [self layer].contents = (id)cgimg;
+    CGImageRelease(cgimg);
+  }
+}
+
+-(void)viewFrameDidChange
+{
+    CGContextRelease(layer_gc);
+    layer_gc = NULL;
+}
+-(void)dealloc {
+  CGContextRelease(layer_gc);
+  [super dealloc];
+}
+#endif //>= MAC_OS_X_VERSION_10_8
+
+- (BOOL)did_view_resolution_change {
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+  if (fl_mac_os_version >= 100700) { // determine whether window is mapped to a retina display
+    Fl_Window *window = [(FLWindow*)[self window] getFl_Window];
+    Fl_Cocoa_Window_Driver *d = Fl_Cocoa_Window_Driver::driver(window);
+    bool previous = d->mapped_to_retina();
+    NSSize s = [self convertSizeToBacking:NSMakeSize(10, 10)]; // 10.7
+    d->mapped_to_retina( int(s.width + 0.5) > 10 );
+    BOOL retval = (d->wait_for_expose_value == 0 && previous != d->mapped_to_retina());
+    if (retval) d->changed_resolution(true);
+    return retval;
+  }
+#endif
+  return NO;
+}
+
 - (BOOL)process_keydown:(NSEvent*)theEvent
 {
   id o = fl_mac_os_version >= 100600 ? [self performSelector:@selector(inputContext)] : [FLTextInputContext singleInstance];
@@ -2139,7 +2326,7 @@ static FLTextInputContext* fltextinputcontext_instance = nil;
 }
 
 /*
- * Gets called when a window is created or resized, or moved between retina and non-retina displays
+ * Gets called when a non-layered window is created or resized, or moved between retina and non-retina displays
  * (with Mac OS ≥ 10.11 also when deminiaturized)
  */
 - (void)drawRect:(NSRect)rect
@@ -2155,17 +2342,8 @@ static FLTextInputContext* fltextinputcontext_instance = nil;
   }
   through_drawRect = YES;
   Fl_Cocoa_Window_Driver *d = Fl_Cocoa_Window_Driver::driver(window);
-  if (fl_mac_os_version >= 100700) { // determine whether window is mapped to a retina display
-    bool previous = d->mapped_to_retina();
-    // rewrite next call that requires 10.7 and therefore triggers a compiler warning on old SDKs
-    //NSSize s = [[cw contentView] convertSizeToBacking:NSMakeSize(10, 10)];
-    typedef NSSize (*convertSizeIMP)(id, SEL, NSSize);
-    static convertSizeIMP addr = (convertSizeIMP)[NSView instanceMethodForSelector:@selector(convertSizeToBacking:)];
-    NSSize s = addr([cw contentView], @selector(convertSizeToBacking:), NSMakeSize(10, 10));
-    d->mapped_to_retina( int(s.width + 0.5) > 10 );
-    if (d->wait_for_expose_value == 0 && previous != d->mapped_to_retina()) d->changed_resolution(true);
-  }
-  d->wait_for_expose_value = 0;
+  [self did_view_resolution_change];
+  if (!views_use_CA) d->wait_for_expose_value = 0;
   Fl_X *i = Fl_X::i(window);
   if ( i->region ) {
     Fl_Graphics_Driver::default_driver().XDestroyRegion(i->region);
@@ -2770,11 +2948,13 @@ void Fl_Cocoa_Gl_Window_Driver::GLcontext_makecurrent(NSOpenGLContext* ctxt)
 
 /*
  * Initialize the given port for redraw and call the window's flush() to actually draw the content
- */ 
+ */
 void Fl_Cocoa_Window_Driver::flush()
 {
   if (pWindow->as_gl_window()) {
     Fl_Window_Driver::flush();
+  } else if (views_use_CA) {
+    [[fl_xid(pWindow) contentView] updateLayer];
   } else {
     make_current_counts = 1;
     NSView *view = (through_drawRect ? nil : [fl_xid(pWindow) contentView]);
@@ -2944,7 +3124,12 @@ Fl_X* Fl_Cocoa_Window_Driver::makeWindow()
     x->next = NULL;
     Fl_X::first = x;
   }
-  FLView *myview = [[FLView alloc] initWithFrame:crect];
+  FLView *myview =
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+    views_use_CA && w->as_gl_window() ? [FLViewGL alloc] :
+#endif
+    [FLView alloc];
+  myview = [myview initWithFrame:crect];
   [cw setContentView:myview];
   [myview release];
   [cw setLevel:winlevel];
@@ -3214,10 +3399,14 @@ void Fl_Cocoa_Window_Driver::resize(int X,int Y,int W,int H) {
  */
 void Fl_Cocoa_Window_Driver::make_current()
 {
-  if (make_current_counts > 1) return;
+  if (make_current_counts > 1 && !views_use_CA) return;
   if (make_current_counts) make_current_counts++;
+  if (views_use_CA && !through_drawRect) {
+    pWindow->damage(FL_DAMAGE_CHILD); // force display of previous draws to this window
+  }
   q_release_context();
   Fl_X *i = Fl_X::i(pWindow);
+  //NSLog(@"region-count=%d damage=%u",i->region?i->region->count:0, pWindow->damage());
   fl_window = i->xid;
   ((Fl_Quartz_Graphics_Driver&)Fl_Graphics_Driver::default_driver()).high_resolution( mapped_to_retina() );
   
@@ -3225,20 +3414,18 @@ void Fl_Cocoa_Window_Driver::make_current()
     destroy_double_buffer();
     changed_resolution(false);
   }
-  /*NSGraphicsContext *nsgc;
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
-  if (fl_mac_os_version >= 100400)
-    nsgc = [fl_window graphicsContext]; // 10.4
-  else
-#endif*/
-    NSGraphicsContext *nsgc = through_Fl_X_flush ? [NSGraphicsContext currentContext] : [NSGraphicsContext graphicsContextWithWindow:fl_window];
-    if (!nsgc) { // this occurs on 10.14 when through_Fl_X_flush==0
-        [[fl_window contentView] lockFocus];
-        nsgc = [NSGraphicsContext currentContext];
-    }
-  gc = (CGContextRef)[nsgc graphicsPort];
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+  if (views_use_CA) {
+    gc = ((FLView*)[fl_window contentView])->layer_gc;
+  } else
+#endif
+  {
+    NSGraphicsContext *nsgc =   through_Fl_X_flush ? [NSGraphicsContext currentContext] : [NSGraphicsContext graphicsContextWithWindow:fl_window];
+    gc = (CGContextRef)[nsgc graphicsPort];
+  }
   Fl_Graphics_Driver::default_driver().gc(gc);
   CGContextSaveGState(gc); // native context
+  if (views_use_CA && mapped_to_retina()) CGContextScaleCTM(gc, 2,2);
   // antialiasing must be deactivated because it applies to rectangles too
   // and escapes even clipping!!!
   // it gets activated when needed (e.g., draw text)
@@ -4058,22 +4245,20 @@ static NSBitmapImageRep* GL_rect_to_nsbitmap(Fl_Window *win, int x, int y, int w
   return bitmap;
 }
 
-static NSBitmapImageRep* rect_to_NSBitmapImageRep_noredraw(Fl_Window *win, int x, int y, int w, int h)
-{
-// under macOS 10.14 and when linked with 10.14 SDK, initWithFocusedViewRect: does not work
-// this other procedure does capture screen data, but does not capture window parts outside the screen
+static NSBitmapImageRep* rect_to_NSBitmapImageRep_layer(Fl_Window *win, int x, int y, int w, int h)
+{ // capture window data for layer-based views because initWithFocusedViewRect: does not work for them
   NSBitmapImageRep *bitmap = nil;
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-  NSRect wrect = [fl_xid(win) frame]; // window on screen from bottom
-  int bx, by, bt;
-  get_window_frame_sizes(bx, by, bt, win);
-  wrect.size.height -= bt; // exclude titlebar
-  wrect.origin.y = main_screen_height - (wrect.origin.y + wrect.size.height); // window on screen from top
-  CGRect cgbounds = NSRectToCGRect(wrect);//10.5
-  float s = Fl_Graphics_Driver::default_driver().scale();
-  cgbounds.origin.x += x*s +0.5; cgbounds.origin.y += y*s +0.5;
-  cgbounds.size.width = w*s; cgbounds.size.height = h*s;
-  CGImageRef cgimg = CGWindowListCreateImage(cgbounds, kCGWindowListOptionIncludingWindow, [fl_xid(win) windowNumber], kCGWindowImageBoundsIgnoreFraming); //10.5
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+  CGContextRef gc = ((FLView*)[fl_xid(win) contentView])->layer_gc;
+  CGImageRef cgimg = CGBitmapContextCreateImage(gc);  // requires 10.4
+  float s = Fl::screen_driver()->scale(0);
+  int resolution = Fl_Cocoa_Window_Driver::driver(win->top_window())->mapped_to_retina() ? 2 : 1;
+  if (x || y || w != win->w() || h != win->h()) {
+    CGRect rect = CGRectMake(x * s * resolution, y * s * resolution, w * s * resolution, h * s * resolution);
+    CGImageRef cgimg2 = CGImageCreateWithImageInRect(cgimg, rect);
+    CGImageRelease(cgimg);
+    cgimg = cgimg2;
+  }
   bitmap = [[NSBitmapImageRep alloc] initWithCGImage:cgimg];//10.5
   CGImageRelease(cgimg);
 #endif
@@ -4091,10 +4276,8 @@ static NSBitmapImageRep* rect_to_NSBitmapImageRep(Fl_Window *win, int x, int y,
   float s = Fl_Graphics_Driver::default_driver().scale();
   if (win->as_gl_window() && y >= 0) {
     bitmap = GL_rect_to_nsbitmap(win, x, y, w, h);
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-  } else if (fl_mac_os_version >= 101400 && [[fl_xid(win) contentView] layer /*10.5*/]) {
-    bitmap = rect_to_NSBitmapImageRep_noredraw(win, x, y, w, h);
-#endif
+  } else if (views_use_CA) {
+    bitmap = rect_to_NSBitmapImageRep_layer(win, x, y, w, h);
   } else {
     NSView *winview = nil;
     if ( through_Fl_X_flush  && Fl_Window::current() == win ) {
@@ -4288,7 +4471,12 @@ int Fl_Darwin_System_Driver::calc_mac_os_version() {
     sscanf(s, "%d.%d.%d", &M, &m, &b);
   }
   [localPool release];
-  return fl_mac_os_version = M*10000 + m*100 + b;
+  fl_mac_os_version = M*10000 + m*100 + b;
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_14
+  if (fl_mac_os_version >= 101400) views_use_CA = YES;
+#endif
+  //if (fl_mac_os_version >= 101300) views_use_CA = YES;  // to get as with mojave
+  return fl_mac_os_version;
 }
 
 //