(x_calc_absolute_position): Fix frame positioning

with negative X/Y coordinates.
From Francis Litterio <franl@world.std.com>

diff --git a/src/w32term.c b/src/w32term.c
index 29fe961946d1b5e9c6aeba01827fc085b9cf07cd..294059aa77bbb598df55eaaba7df7394f016903a 100644 (file)
--- a/src/w32term.c
+++ b/src/w32term.c
@@ -5312,20 +5312,52 @@ x_calc_absolute_position (f)
 {
   int flags = f->size_hint_flags;
 
-  /* Treat negative positions as relative to the leftmost bottommost
+  /* The sum of the widths of the frame's left and right borders, and
+     the sum of the heights of the frame's top and bottom borders (in
+     pixels) drawn by Windows.  */
+  unsigned int left_right_borders_width, top_bottom_borders_height;
+
+  /* Try to get the actual values of these two variables.  We compute
+     the border width (height) by subtracting the width (height) of
+     the frame's client area from the width (height) of the frame's
+     entire window.  */
+  WINDOWPLACEMENT wp = { 0 };
+  RECT client_rect = { 0 };
+
+  if (GetWindowPlacement (FRAME_W32_WINDOW (f), &wp)
+      && GetClientRect (FRAME_W32_WINDOW (f), &client_rect))
+    {
+      left_right_borders_width =
+       (wp.rcNormalPosition.right - wp.rcNormalPosition.left) -
+       (client_rect.right - client_rect.left);
+
+      top_bottom_borders_height =
+       (wp.rcNormalPosition.bottom - wp.rcNormalPosition.top) -
+       (client_rect.bottom - client_rect.top);
+    }
+  else
+    {
+      /* Use sensible default values.  */
+      left_right_borders_width = 8;
+      top_bottom_borders_height = 32;
+    }
+
+  /* Treat negative positions as relative to the rightmost bottommost
      position that fits on the screen.  */
   if (flags & XNegative)
     f->left_pos = (FRAME_W32_DISPLAY_INFO (f)->width
                   - FRAME_PIXEL_WIDTH (f)
-                  + f->left_pos);
+                  + f->left_pos
+                  - (left_right_borders_width - 1));
 
   if (flags & YNegative)
     f->top_pos = (FRAME_W32_DISPLAY_INFO (f)->height
                  - FRAME_PIXEL_HEIGHT (f)
-                 + f->top_pos);
-  /* The left_pos and top_pos
-     are now relative to the top and left screen edges,
-     so the flags should correspond.  */
+                 + f->top_pos
+                 - (top_bottom_borders_height - 1));
+
+  /* The left_pos and top_pos are now relative to the top and left
+     screen edges, so the flags should correspond.  */
   f->size_hint_flags &= ~ (XNegative | YNegative);
 }