Subject: bug#54623: No scroll bars on macOS builds

From: Alan Third <[email-masked]>
Date: Sun, 3 Apr 2022 14:36:13 +0100

On Sat, Apr 02, 2022 at 01:00:13PM +0200, Angelo Graziosi wrote:
> 
> > Il 02/04/2022 11:42 Angelo Graziosi <[email-masked]> ha scritto:
> > 
> >  
> > > Il 02/04/2022 10:07 Alan Third <[email-masked]> ha scritto:
> > > 
> > >  
> > > On Sat, Apr 02, 2022 at 12:37:33AM +0200, Angelo Graziosi wrote:
> > > > Undefined symbols for architecture x86_64:
> > > >   "_OBJC_CLASS_$_EmacsLayer", referenced from:
> > > >       objc-class-ref in nsterm.o
> > > > ld: symbol(s) not found for architecture x86_64
> > > > clang: error: linker command failed with exit code 1 (use -v to see invocation)
> > > > make[1]: *** [temacs] Error 1
> > > > make: *** [src] Error 2
> > > > Error: Failure running MAKE
> > > 
> > > *sigh* missed a zero in the version number in one of the #if things.
> > > 
> > > Please try the attached.
> > 
> > Now it seems to work as expected!!!
> > 
> > Let's see how t work for few days..
> 
> Spoken too soon!
> =================
> 
> Now Emacs builds, does not crash, *does have* scroll bars, but..
> 
> - I cannot select text (mouse-1 and drag)
> 
> - minibuffer does not work: C-x C-f displays current directory but I cannot type anything there
> 
> - the same with M-x: only M-x is displayed but cannot type the command and cannot use history (UP/DOWN arrows)..

hopefully all we have to do is force an occasional redraw like on
GNUstep. Please try the attached.
-- 
Alan Third
>From 0ceb4141eaaac896cc1a16aa58cc11f037048906 Mon Sep 17 00:00:00 2001
From: Alan Third <[email-masked]>
Date: Wed, 30 Mar 2022 22:40:03 +0100
Subject: [PATCH v5] Fix scrollbars on macOS 10.13 and below (bug#54623)

Make any build on macOS 10.13 and below follow the same drawing path
as the GNUstep port.  macOS 10.14 and above will use EmacsLayer.

* src/nsterm.h (EmacsLayer):
* src/nsterm.m ([EmacsView makeBackingLayer]):
([EmacsView unlockFocus]):
([EmacsView windowDidChangeBackingProperties:]):
([EmacsView copyRect:to:]): Remove any code required for macOS 10.13
and below, and fix the #if's to enforce strict separation of the
drawing paths.
(ns_update_end):
(ns_unfocus): Fix #ifs so that flushWindow is called on old macOS
versions as well as GNUstep.
---
 src/nsterm.h |   4 +-
 src/nsterm.m | 128 +++++++++++++++++++--------------------------------
 2 files changed, 50 insertions(+), 82 deletions(-)

diff --git a/src/nsterm.h b/src/nsterm.h
index f027646123..4cba5c0be8 100644
--- a/src/nsterm.h
+++ b/src/nsterm.h
@@ -487,7 +487,7 @@ #define NSTRACE_UNSILENCE()
 #endif
 - (int)fullscreenState;
 
-#ifdef NS_IMPL_COCOA
+#if defined (NS_IMPL_COCOA) && MAC_OS_X_VERSION_MIN_REQUIRED >= 101400
 - (void)lockFocus;
 - (void)unlockFocus;
 #endif
@@ -698,7 +698,7 @@ #define NSTRACE_UNSILENCE()
 + (CGFloat)scrollerWidth;
 @end
 
-#ifdef NS_IMPL_COCOA
+#if defined (NS_IMPL_COCOA) && MAC_OS_X_VERSION_MIN_REQUIRED >= 101400
 @interface EmacsLayer : CALayer
 {
   NSMutableArray *cache;
diff --git a/src/nsterm.m b/src/nsterm.m
index fd56094c28..0520d76b34 100644
--- a/src/nsterm.m
+++ b/src/nsterm.m
@@ -1060,7 +1060,7 @@ static NSRect constrain_frame_rect(NSRect frameRect, bool isFullscreen)
   block_input ();
 
   [view unlockFocus];
-#if defined (NS_IMPL_GNUSTEP)
+#if defined (NS_IMPL_GNUSTEP) || MAC_OS_X_VERSION_MIN_REQUIRED < 101400
   [[view window] flushWindow];
 #endif
 
@@ -1127,7 +1127,7 @@ static NSRect constrain_frame_rect(NSRect frameRect, bool isFullscreen)
     {
       EmacsView *view = FRAME_NS_VIEW (f);
       [view unlockFocus];
-#if defined (NS_IMPL_GNUSTEP)
+#if defined (NS_IMPL_GNUSTEP) || MAC_OS_X_VERSION_MIN_REQUIRED < 101400
       [[view window] flushWindow];
 #endif
     }
@@ -7197,7 +7197,7 @@ - (instancetype) initFrameFromEmacs: (struct frame *)f
 
   [[EmacsWindow alloc] initWithEmacsFrame:f];
 
-#ifdef NS_IMPL_COCOA
+#if defined (NS_IMPL_COCOA) && MAC_OS_X_VERSION_MIN_REQUIRED >= 101400
   /* These settings mean AppKit will retain the contents of the frame
      on resize.  Unfortunately it also means the frame will not be
      automatically marked for display, but we can do that ourselves in
@@ -7861,7 +7861,7 @@ - (instancetype)toggleToolbar: (id)sender
 }

-#ifdef NS_IMPL_COCOA
+#if defined (NS_IMPL_COCOA) && MAC_OS_X_VERSION_MIN_REQUIRED >= 101400
 - (CALayer *)makeBackingLayer;
 {
   EmacsLayer *l = [[EmacsLayer alloc]
@@ -7877,19 +7877,12 @@ - (void)lockFocus
 {
   NSTRACE ("[EmacsView lockFocus]");
 
-  if ([self wantsLayer])
-    {
-      CGContextRef context = [(EmacsLayer*)[self layer] getContext];
+  CGContextRef context = [(EmacsLayer*)[self layer] getContext];
 
-      [NSGraphicsContext
+  [NSGraphicsContext
         setCurrentContext:[NSGraphicsContext
                             graphicsContextWithCGContext:context
                                                  flipped:YES]];
-    }
-#if MAC_OS_X_VERSION_MIN_REQUIRED < 101400
-  else
-    [super lockFocus];
-#endif
 }

@@ -7897,18 +7890,8 @@ - (void)unlockFocus
 {
   NSTRACE ("[EmacsView unlockFocus]");
 
-  if ([self wantsLayer])
-    {
-      [NSGraphicsContext setCurrentContext:nil];
-      [self setNeedsDisplay:YES];
-    }
-#if MAC_OS_X_VERSION_MIN_REQUIRED < 101400
-  else
-    {
-      [super unlockFocus];
-      [super flushWindow];
-    }
-#endif
+  [NSGraphicsContext setCurrentContext:nil];
+  [self setNeedsDisplay:YES];
 }

@@ -7917,19 +7900,16 @@ - (void)windowDidChangeBackingProperties:(NSNotification *)notification
 {
   NSTRACE ("EmacsView windowDidChangeBackingProperties:]");
 
-  if ([self wantsLayer])
-    {
-      NSRect frame = [self frame];
-      EmacsLayer *layer = (EmacsLayer *)[self layer];
+  NSRect frame = [self frame];
+  EmacsLayer *layer = (EmacsLayer *)[self layer];
 
-      [layer setContentsScale:[[notification object] backingScaleFactor]];
-      [layer setColorSpace:[[[notification object] colorSpace] CGColorSpace]];
+  [layer setContentsScale:[[notification object] backingScaleFactor]];
+  [layer setColorSpace:[[[notification object] colorSpace] CGColorSpace]];
 
-      ns_clear_frame (emacsframe);
-      expose_frame (emacsframe, 0, 0, NSWidth (frame), NSHeight (frame));
-    }
+  ns_clear_frame (emacsframe);
+  expose_frame (emacsframe, 0, 0, NSWidth (frame), NSHeight (frame));
 }
-#endif /* NS_IMPL_COCOA */
+#endif

 - (void)copyRect:(NSRect)srcRect to:(NSPoint)dest
@@ -7941,57 +7921,45 @@ - (void)copyRect:(NSRect)srcRect to:(NSPoint)dest
   NSRect dstRect = NSMakeRect (dest.x, dest.y, NSWidth (srcRect),
                                NSHeight (srcRect));
 
-#ifdef NS_IMPL_COCOA
-  if ([self wantsLayer])
-    {
-      double scale = [[self window] backingScaleFactor];
-      CGContextRef context = [(EmacsLayer *)[self layer] getContext];
-      int bpp = CGBitmapContextGetBitsPerPixel (context) / 8;
-      void *pixels = CGBitmapContextGetData (context);
-      int rowSize = CGBitmapContextGetBytesPerRow (context);
-      int srcRowSize = NSWidth (srcRect) * scale * bpp;
-      void *srcPixels = (char *) pixels
-                        + (int) (NSMinY (srcRect) * scale * rowSize
-                                 + NSMinX (srcRect) * scale * bpp);
-      void *dstPixels = (char *) pixels
-                        + (int) (dest.y * scale * rowSize
-                                 + dest.x * scale * bpp);
-
-      if (NSIntersectsRect (srcRect, dstRect)
-          && NSMinY (srcRect) < NSMinY (dstRect))
-        for (int y = NSHeight (srcRect) * scale - 1 ; y >= 0 ; y--)
-          memmove ((char *) dstPixels + y * rowSize,
-                   (char *) srcPixels + y * rowSize,
-                   srcRowSize);
-      else
-        for (int y = 0 ; y < NSHeight (srcRect) * scale ; y++)
-          memmove ((char *) dstPixels + y * rowSize,
-                   (char *) srcPixels + y * rowSize,
-                   srcRowSize);
-
-    }
-#if MAC_OS_X_VERSION_MIN_REQUIRED < 101400
+#if defined (NS_IMPL_COCOA) && MAC_OS_X_VERSION_MIN_REQUIRED >= 101400
+  double scale = [[self window] backingScaleFactor];
+  CGContextRef context = [(EmacsLayer *)[self layer] getContext];
+  int bpp = CGBitmapContextGetBitsPerPixel (context) / 8;
+  void *pixels = CGBitmapContextGetData (context);
+  int rowSize = CGBitmapContextGetBytesPerRow (context);
+  int srcRowSize = NSWidth (srcRect) * scale * bpp;
+  void *srcPixels = (char *) pixels
+    + (int) (NSMinY (srcRect) * scale * rowSize
+             + NSMinX (srcRect) * scale * bpp);
+  void *dstPixels = (char *) pixels
+    + (int) (dest.y * scale * rowSize
+             + dest.x * scale * bpp);
+
+  if (NSIntersectsRect (srcRect, dstRect)
+      && NSMinY (srcRect) < NSMinY (dstRect))
+    for (int y = NSHeight (srcRect) * scale - 1 ; y >= 0 ; y--)
+      memmove ((char *) dstPixels + y * rowSize,
+               (char *) srcPixels + y * rowSize,
+               srcRowSize);
   else
-    {
-#endif
-#endif /* NS_IMPL_COCOA */
+    for (int y = 0 ; y < NSHeight (srcRect) * scale ; y++)
+      memmove ((char *) dstPixels + y * rowSize,
+               (char *) srcPixels + y * rowSize,
+               srcRowSize);
 
-#if !defined (NS_IMPL_COCOA) || MAC_OS_X_VERSION_MIN_REQUIRED < 101400
-      hide_bell();              // Ensure the bell image isn't scrolled.
+#else
+  hide_bell();              // Ensure the bell image isn't scrolled.
 
-      ns_focus (emacsframe, &dstRect, 1);
-      [self scrollRect: srcRect
-                    by: NSMakeSize (dstRect.origin.x - srcRect.origin.x,
-                                    dstRect.origin.y - srcRect.origin.y)];
-      ns_unfocus (emacsframe);
-#endif
-#if defined (NS_IMPL_COCOA) && MAC_OS_X_VERSION_MIN_REQUIRED < 101400
-    }
+  ns_focus (emacsframe, &dstRect, 1);
+  [self scrollRect: srcRect
+                by: NSMakeSize (dstRect.origin.x - srcRect.origin.x,
+                                dstRect.origin.y - srcRect.origin.y)];
+  ns_unfocus (emacsframe);
 #endif
 }

-#ifdef NS_IMPL_COCOA
+#if defined (NS_IMPL_COCOA) && MAC_OS_X_VERSION_MIN_REQUIRED >= 101400
 /* If the frame has been garbaged but the toolkit wants to draw, for
    example when resizing the frame, we end up with a blank screen.
    Sometimes this results in an unpleasant flicker, so try to
@@ -9435,7 +9403,7 @@ - (void) scrollWheel: (NSEvent *)theEvent
 @end  /* EmacsScroller */

-#ifdef NS_IMPL_COCOA
+#if defined (NS_IMPL_COCOA) && MAC_OS_X_VERSION_MIN_REQUIRED >= 101400
 
 /* ==========================================================================
 
-- 
2.35.1