talons

commit 7626388b45d8bd87b2f78cd89f76b52e9116bf7c
parent b7e8f5299b20bba15aca74d4d6702aef4ad6d94f
Author: Jonathan Boeing <jonathan.n.boeing@gmail.com>
Date:   Sun, 28 Feb 2021 18:56:08 -0700

Double-buffer row drawing in gtkcmctree

This patch fixes the slowness seen when redrawing the folder tree with
cairo > 1.10 on Windows.  It also improves the occasionally visible
flickering in the folder tree on Linux and Windows with older versions
of cairo.

Diffstat:
M
configure.ac
 | 
2
+-
M
src/gtk/gtkcmctree.c
 | 
21
++++++++++++++++++++-

2 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/configure.ac b/configure.ac
@@ -1234,7 +1234,7 @@ AC_SUBST(GDATA_CFLAGS)
 AC_SUBST(GDATA_LIBS)
 
 dnl cairo **********************************************************************
-PKG_CHECK_MODULES(CAIRO, cairo, HAVE_CAIRO=yes, HAVE_CAIRO=no)
+PKG_CHECK_MODULES(CAIRO, cairo >= 1.12.0, HAVE_CAIRO=yes, HAVE_CAIRO=no)
 AC_SUBST(CAIRO_CFLAGS)
 AC_SUBST(CAIRO_LIBS)
 
diff --git a/src/gtk/gtkcmctree.c b/src/gtk/gtkcmctree.c
@@ -599,6 +599,8 @@ draw_row (GtkCMCList     *clist,
   static GdkColor greybg={0, 0, 0, 0};
   static gboolean color_change = TRUE;
   cairo_t *cr;
+  cairo_t *cr_hw;
+  cairo_surface_t *image_surface;
   GdkColor *fgcolor, *bgcolor;
 
   cm_return_if_fail (clist != NULL);
@@ -667,7 +669,12 @@ draw_row (GtkCMCList     *clist,
   }
   state = clist_row->state;
 
-  cr = gdk_cairo_create(clist->clist_window);
+  cr_hw = gdk_cairo_create(clist->clist_window);
+  image_surface = cairo_surface_create_similar_image(cairo_get_target(cr_hw),
+                                                     CAIRO_FORMAT_RGB24,
+                                                     gdk_window_get_width(clist->clist_window),
+                                                     gdk_window_get_height(clist->clist_window));
+  cr = cairo_create(image_surface);
   
   if (clist_row->fg_set && state != GTK_STATE_SELECTED)
 	fgcolor = &clist_row->foreground;
@@ -937,7 +944,19 @@ draw_row (GtkCMCList     *clist,
 	    cairo_stroke(cr);
 	}
      }
+
+    cairo_set_operator(cr_hw, CAIRO_OPERATOR_SOURCE);
+    cairo_set_source_surface(cr_hw, image_surface, 0, 0);
+    cairo_rectangle(cr_hw,
+                    row_rectangle.x,
+                    row_rectangle.y - CELL_SPACING,
+                    row_rectangle.width,
+                    row_rectangle.height + CELL_SPACING * 2);
+    cairo_fill(cr_hw);
+
     cairo_destroy(cr);
+    cairo_surface_destroy(image_surface);
+    cairo_destroy(cr_hw);
 }
 
 static void