From 60651650603a1977becef7c5cfa6cc14b99ca89f Mon Sep 17 00:00:00 2001
From: Benjamin Otte <otte@redhat.com>
Date: Wed, 10 Jul 2024 08:31:53 +0200
Subject: [PATCH] Add gdk_dihedral_swaps_xy

This function determines if a dihedral transform swaps x and y.
---
 gdk/gdkdihedral.c        |  5 +++++
 gdk/gdkdihedralprivate.h |  1 +
 gsk/gskroundedrect.c     |  2 +-
 testsuite/gdk/dihedral.c | 14 ++++++++++++++
 4 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/gdk/gdkdihedral.c b/gdk/gdkdihedral.c
index f9286a9e61..6628e6fc60 100644
--- a/gdk/gdkdihedral.c
+++ b/gdk/gdkdihedral.c
@@ -65,3 +65,8 @@ gdk_dihedral_invert (GdkDihedral self)
   return ((4 - self) * (((self & 4) >> 1) + 1) & 3) | (self & 4);
 }
 
+gboolean
+gdk_dihedral_swaps_xy (GdkDihedral self)
+{
+  return (self & 1) ? TRUE : FALSE;
+}
diff --git a/gdk/gdkdihedralprivate.h b/gdk/gdkdihedralprivate.h
index 699775d8c2..472cd74a1a 100644
--- a/gdk/gdkdihedralprivate.h
+++ b/gdk/gdkdihedralprivate.h
@@ -41,6 +41,7 @@ void            gdk_dihedral_get_mat2                           (GdkDihedral
 GdkDihedral     gdk_dihedral_combine                            (GdkDihedral            first,
                                                                  GdkDihedral            second);
 GdkDihedral     gdk_dihedral_invert                             (GdkDihedral            self);
+gboolean        gdk_dihedral_swaps_xy                           (GdkDihedral            self);
 
 G_END_DECLS
 
diff --git a/gsk/gskroundedrect.c b/gsk/gskroundedrect.c
index 7306bb5d0f..df2b1af370 100644
--- a/gsk/gskroundedrect.c
+++ b/gsk/gskroundedrect.c
@@ -331,7 +331,7 @@ gsk_rounded_rect_dihedral (GskRoundedRect       *dest,
 
   gsk_rect_dihedral (&src->bounds, dihedral, &dest->bounds);
 
-  if (dihedral & 1)
+  if (gdk_dihedral_swaps_xy (dihedral))
     {
       for (i = 0; i < 4; i++)
         {
diff --git a/testsuite/gdk/dihedral.c b/testsuite/gdk/dihedral.c
index f7e715aa79..580af8f997 100644
--- a/testsuite/gdk/dihedral.c
+++ b/testsuite/gdk/dihedral.c
@@ -64,12 +64,26 @@ test_inversions (void)
   g_assert_cmpint (gdk_dihedral_invert (GDK_DIHEDRAL_FLIPPED_270), ==, GDK_DIHEDRAL_FLIPPED_270);
 }
 
+static void
+test_swaps (void)
+{
+  g_assert_false (gdk_dihedral_swaps_xy (GDK_DIHEDRAL_NORMAL));
+  g_assert_true (gdk_dihedral_swaps_xy (GDK_DIHEDRAL_90));
+  g_assert_false (gdk_dihedral_swaps_xy (GDK_DIHEDRAL_180));
+  g_assert_true (gdk_dihedral_swaps_xy (GDK_DIHEDRAL_270));
+  g_assert_false (gdk_dihedral_swaps_xy (GDK_DIHEDRAL_FLIPPED));
+  g_assert_true (gdk_dihedral_swaps_xy (GDK_DIHEDRAL_FLIPPED_90));
+  g_assert_false (gdk_dihedral_swaps_xy (GDK_DIHEDRAL_FLIPPED_180));
+  g_assert_true (gdk_dihedral_swaps_xy (GDK_DIHEDRAL_FLIPPED_270));
+}
+
 int
 main (int argc, char *argv[])
 {
   gtk_test_init (&argc, &argv, NULL);
 
   g_test_add_func ("/dihedral/inversions", test_inversions);
+  g_test_add_func ("/dihedral/swaps", test_swaps);
   g_test_add_func ("/dihedral/combinations", test_combinations);
   g_test_add_func ("/dihedral/invariants", test_invariants);