Improve window dividers code.

* faces.el (window-divider): New default value.  Rewrite
doc-string.
(window-divider-first-pixel, window-divider-last-pixel): New
faces.
* dispextern.h (face_id): Add WINDOW_DIVIDER_FIRST_PIXEL_FACE_ID
and WINDOW_DIVIDER_LAST_PIXEL_FACE_ID.
* w32term.c (w32_draw_window_divider): Handle first and last
pixels specially.
* w32term.h (w32_fill_area_abs): New function.
* xdisp.c (x_draw_right_divider): Don't draw over bottom
divider.
* xfaces.c (realize_basic_faces): Handle new face ids.
* xfns.c (Fx_create_frame): Call x_default_parameter for right
and bottom divider width.
* xterm.c (x_draw_window_divider): Handle first and last pixels
specially.

1 files changed, 44 insertions, 8 deletions

diff --git a/src/xterm.c b/src/xterm.c
index 685fdf40a70..e1873127276 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -510,15 +510,51 @@ static void
 x_draw_window_divider (struct window *w, int x0, int x1, int y0, int y1)
 {
   struct frame *f = XFRAME (WINDOW_FRAME (w));
-  struct face *face;
-
-  face = FACE_FROM_ID (f, WINDOW_DIVIDER_FACE_ID);
-  if (face)
-    XSetForeground (FRAME_X_DISPLAY (f), f->output_data.x->normal_gc,
-                    face->foreground);
+  struct face *face = FACE_FROM_ID (f, WINDOW_DIVIDER_FACE_ID);
+  struct face *face_first = FACE_FROM_ID (f, WINDOW_DIVIDER_FIRST_PIXEL_FACE_ID);
+  struct face *face_last = FACE_FROM_ID (f, WINDOW_DIVIDER_LAST_PIXEL_FACE_ID);
+  unsigned long color = face ? face->foreground : FRAME_FOREGROUND_PIXEL (f);
+  unsigned long color_first = (face_first
+                               ? face_first->foreground
+                               : FRAME_FOREGROUND_PIXEL (f));
+  unsigned long color_last = (face_last
+                              ? face_last->foreground
+                              : FRAME_FOREGROUND_PIXEL (f));
+  Display *display = FRAME_X_DISPLAY (f);
+  Window window = FRAME_X_WINDOW (f);
 
-  XFillRectangle (FRAME_X_DISPLAY (f), FRAME_X_WINDOW (f),
-                  f->output_data.x->normal_gc, x0, y0, x1 - x0, y1 - y0);
+  if (y1 - y0 > x1 - x0 && x1 - x0 > 2)
+    /* Vertical.  */
+    {
+      XSetForeground (display, f->output_data.x->normal_gc, color_first);
+      XFillRectangle (display, window, f->output_data.x->normal_gc,
+                      x0, y0, 1, y1 - y0);
+      XSetForeground (display, f->output_data.x->normal_gc, color);
+      XFillRectangle (display, window, f->output_data.x->normal_gc,
+                      x0 + 1, y0, x1 - x0 - 2, y1 - y0);
+      XSetForeground (display, f->output_data.x->normal_gc, color_last);
+      XFillRectangle (display, window, f->output_data.x->normal_gc,
+                      x1 - 1, y0, 1, y1 - y0);
+    }
+  else if (x1 - x0 > y1 - y0 && y1 - y0 > 3)
+    /* Horizontal.  */
+    {
+      XSetForeground (display, f->output_data.x->normal_gc, color_first);
+      XFillRectangle (display, window, f->output_data.x->normal_gc,
+                      x0, y0, x1 - x0, 1);
+      XSetForeground (display, f->output_data.x->normal_gc, color);
+      XFillRectangle (display, window, f->output_data.x->normal_gc,
+                      x0, y0 + 1, x1 - x0, y1 - y0 - 2);
+      XSetForeground (display, f->output_data.x->normal_gc, color_last);
+      XFillRectangle (display, window, f->output_data.x->normal_gc,
+                      x0, y1 - 1, x1 - x0, 1);
+    }
+  else
+    {
+      XSetForeground (display, f->output_data.x->normal_gc, color);
+      XFillRectangle (display, window, f->output_data.x->normal_gc,
+                      x0, y0, x1 - x0, y1 - y0);
+    }
 }
 
 /* End update of window W.