[gimp-macos-build/wip/Jehan/GDK-expose-too-much: 2/2] patches, modulesets: add a patch to expose smaller redraw rectangles.

[Jehan <jehanp src gnome org>]

commit 4417b5773fb1db874defb5f3c6d28bb9493fd9ef
Author: Jehan <jehan girinstud io>
Date:   Sun Feb 13 16:47:12 2022 +0100

    patches, modulesets: add a patch to expose smaller redraw rectangles.

 modulesets/gtk-osx.modules                         |  1 +
 ...tz-send-expose-events-for-individual-dama.patch | 87 ++++++++++++++++++++++
 2 files changed, 88 insertions(+)
---
diff --git a/modulesets/gtk-osx.modules b/modulesets/gtk-osx.modules
index 5f723f9..d3a770e 100644
--- a/modulesets/gtk-osx.modules
+++ b/modulesets/gtk-osx.modules
@@ -289,6 +289,7 @@
       <!-- Use cairo_image_surfaces for most drawing. Once
            https://gitlab.gnome.org/GNOME/gtk/-/issues/3714 is closed, this can be removed -->
       <patch file="gtk-3.24.31-use-cairo-surface-for-drawing.patch" strip="1"/>
+      <patch file="gtk3-gdk-in-Quartz-send-expose-events-for-individual-dama.patch" strip="1"/>
     </branch>
     <dependencies>
       <dep package="glib"/>
diff --git a/patches/gtk3-gdk-in-Quartz-send-expose-events-for-individual-dama.patch 
b/patches/gtk3-gdk-in-Quartz-send-expose-events-for-individual-dama.patch
new file mode 100644
index 0000000..8070a0a
--- /dev/null
+++ b/patches/gtk3-gdk-in-Quartz-send-expose-events-for-individual-dama.patch
@@ -0,0 +1,87 @@
+From 4e2c4129a71de6f03ce36ff67b7ffab95ac800d2 Mon Sep 17 00:00:00 2001
+From: Jehan <jehan girinstud io>
+Date: Sun, 13 Feb 2022 16:29:11 +0100
+Subject: [PATCH] gdk: in Quartz, send expose events for individual damaged
+ regions.
+
+Current code was unioning the various regions returned by
+getRectsBeingDrawn. Unfortunately cairo/pixman unions are not real
+boolean geometry union operations. It creates a bounding box of the
+input regions. So if we have a pixel to the bottom left of a big area
+and a pixel to the top right, we might end up invalidating the whole
+area needlessly. And if this often happens, we are just constantly
+redrawing everything.
+
+This is a problem which happens in GIMP because our canvas has a
+position label and rulers constantly changing when cursor moves, so when
+you move the pointer, the GUI ends up redrawing nearly the whole canvas
+constantly (instead of a few small rectangles).
+
+Note that on recent macOS, it also requires the code brought from commit
+10b5f8a0d6a to work correctly:
+
+> view.layer.contentsFormat = kCAContentsFormatRGBA8Uint
+
+Without this, getRectsBeingDrawn would itself only return a single
+rectangle of the whole view.
+---
+ gdk/quartz/GdkQuartzView.c | 26 +++++++++++++-------------
+ 1 file changed, 13 insertions(+), 13 deletions(-)
+
+diff --git a/gdk/quartz/GdkQuartzView.c b/gdk/quartz/GdkQuartzView.c
+index c20c5de83a..f3d630ffc2 100644
+--- a/gdk/quartz/GdkQuartzView.c
++++ b/gdk/quartz/GdkQuartzView.c
+@@ -309,12 +309,10 @@
+ 
+ -(void)drawRect: (NSRect)rect
+ {
+-  GdkRectangle gdk_rect;
+   GdkWindowImplQuartz *impl = GDK_WINDOW_IMPL_QUARTZ (gdk_window->impl);
+   const NSRect *drawn_rects;
+   NSInteger count;
+   int i;
+-  cairo_region_t *region;
+ 
+   if (GDK_WINDOW_DESTROYED (gdk_window))
+     return;
+@@ -352,23 +350,25 @@
+     }
+ 
+   [self getRectsBeingDrawn: &drawn_rects count: &count];
+-  region = cairo_region_create ();
+ 
+   for (i = 0; i < count; i++)
+     {
+-      gdk_rect.x = drawn_rects[i].origin.x;
+-      gdk_rect.y = drawn_rects[i].origin.y;
+-      gdk_rect.width = drawn_rects[i].size.width;
+-      gdk_rect.height = drawn_rects[i].size.height;
++      cairo_region_t        *region;
++      cairo_rectangle_int_t  cairo_rect;
+ 
+-      cairo_region_union_rectangle (region, &gdk_rect);
+-    }
++      cairo_rect.x = drawn_rects[i].origin.x;
++      cairo_rect.y = drawn_rects[i].origin.y;
++      cairo_rect.width = drawn_rects[i].size.width;
++      cairo_rect.height = drawn_rects[i].size.height;
++
++      region = cairo_region_create_rectangles (&cairo_rect, 1);
+ 
+-  impl->in_paint_rect_count++;
+-  _gdk_window_process_updates_recurse (gdk_window, region);
+-  impl->in_paint_rect_count--;
++      impl->in_paint_rect_count++;
++      _gdk_window_process_updates_recurse (gdk_window, region);
++      impl->in_paint_rect_count--;
+ 
+-  cairo_region_destroy (region);
++      cairo_region_destroy (region);
++    }
+ 
+   if (needsInvalidateShadow)
+     {
+-- 
+2.30.2
+