From 892ed4877e77da78f9baa48b2bd1b314100e5c68 Mon Sep 17 00:00:00 2001
From: Frederik Carlier <frederik.carlier@keysight.com>
Date: Thu, 4 Apr 2024 22:23:14 +0200
Subject: [PATCH] NSBox: (re-)implement isOpaque (#254)

This (re-)implements logic where a box is marked
as opaque if it is a custom box which is not
transparent, but moves the logic to `GSTheme`,
allowing themes to override this loggic.

This fixes the rendering of custom boxes with a
custom fill color; the current implementation
would mark them as non-opaque and hence the fill
color would not be rendered.

- The original implementation (from 1999) always
  returned `YES`
  (53bcb5024020fe85e370d9d49297aca4320d7768)
- A more complete implementation was backported
  from the Testplant branch in 2012
  (e85b16bc05d5d513788c09b470fd09ad5f888882, by
  @fredkiefer, upstream commit
  36e77b95f7921e9539fdc0c115fe4039fa573150)
- More recently, the a return value of `NO` was
  hardcoded
  (02bc49e2d5336e9092001e3d56cb43750a8466a3, by
  @ericwa)
---
 Headers/Additions/GNUstepGUI/GSTheme.h |  2 ++
 Source/GSThemeDrawing.m                | 12 ++++++++++++
 Source/NSBox.m                         | 13 +------------
 3 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/Headers/Additions/GNUstepGUI/GSTheme.h b/Headers/Additions/GNUstepGUI/GSTheme.h
index b936087fd..dff07525d 100644
--- a/Headers/Additions/GNUstepGUI/GSTheme.h
+++ b/Headers/Additions/GNUstepGUI/GSTheme.h
@@ -1339,6 +1339,8 @@ APPKIT_EXPORT_CLASS
 		 clipRect: (NSRect)clipRect
 		   inView: (NSView *)view;
 
+- (BOOL) isBoxOpaque: (NSBox *)box;
+
 - (void) drawBoxInClipRect: (NSRect)clipRect
 		   boxType: (NSBoxType)boxType
 		borderType: (NSBorderType)borderType
diff --git a/Source/GSThemeDrawing.m b/Source/GSThemeDrawing.m
index 773386076..046b0793b 100644
--- a/Source/GSThemeDrawing.m
+++ b/Source/GSThemeDrawing.m
@@ -3475,6 +3475,18 @@ - (void) drawTableViewRow: (NSInteger)rowIndex
     }
 }
 
+- (BOOL) isBoxOpaque: (NSBox *)box
+{
+  if ([box boxType] == NSBoxCustom)
+    {
+      return ![box isTransparent];
+    }
+  else
+    {
+      return YES;
+    }
+}
+
 - (void) drawBoxInClipRect: (NSRect)clipRect
 		   boxType: (NSBoxType)boxType
 		borderType: (NSBorderType)borderType
diff --git a/Source/NSBox.m b/Source/NSBox.m
index f41a47d40..12f4e88a0 100644
--- a/Source/NSBox.m
+++ b/Source/NSBox.m
@@ -464,18 +464,7 @@ - (void) drawRect: (NSRect)rect
 
 - (BOOL) isOpaque
 {
-  // FIXME: Depends on theme; if always returning NO is a performance hit
-  // we can check if GSTheme is going to draw an old-style opaque box
-  // or not.
-  return NO;
-  // if (_box_type == NSBoxCustom)
-  //   {
-  //     return !_transparent;
-  //   }
-  // else
-  //   {
-  //     return YES;
-  //   }
+  return [[GSTheme theme] isBoxOpaque: self];
 }
 
 - (NSColor*) fillColor