Code holiday commit:

- fix: user pref, window title was reset to 'Blender' on tab usage

- Undo history menu back:
  - name "Undo History"
  - hotkey alt+ctrl+z (alt+apple+z for mac)
  - works like 2.4x, only for global undo, editmode and particle edit.

- Menu scroll
  - for small windows or screens, popup menus now allow to display
    all items, using internal scrolling
  - works with a timer, scrolling 10 items per second when mouse 
    is over the top or bottom arrow
  - if menu is too big to display, it now draws to top or bottom, 
    based on largest available space.
  - also works for hotkey driven pop up menus.

- User pref "DPI" follows widget/layout size
  - widgets & headers now become bigger and smaller, to match 
    'dpi' font sizes. Works well to match UI to monitor size.
  - note that icons can get fuzzy, we need better mipmaps for it

1 files changed, 17 insertions, 2 deletions

diff --git a/source/blender/editors/screen/screen_edit.c b/source/blender/editors/screen/screen_edit.c
index 9bc2b1a402c..eb41dcd147b 100644
--- a/source/blender/editors/screen/screen_edit.c
+++ b/source/blender/editors/screen/screen_edit.c
@@ -671,9 +671,9 @@ static void screen_test_scale(bScreen *sc, int winsizex, int winsizey)
 	/* test for collapsed areas. This could happen in some blender version... */
 	/* ton: removed option now, it needs Context... */
 	
-	/* make each window at least HEADERY high */
+	/* make each window at least ED_area_headersize() high */
 	for(sa= sc->areabase.first; sa; sa= sa->next) {
-		int headery= HEADERY+1;
+		int headery= ED_area_headersize()+1;
 		
 		if(sa->v1->vec.y+headery > sa->v2->vec.y) {
 			/* lower edge */
@@ -1055,6 +1055,18 @@ void ED_screen_draw(wmWindow *win)
 	win->screen->do_draw= 0;
 }
 
+/* helper call for below, dpi changes headers */
+static void screen_refresh_headersizes(void)
+{
+	const ListBase *lb= BKE_spacetypes_list();
+	SpaceType *st;
+	
+	for(st= lb->first; st; st= st->next) {
+		ARegionType *art= BKE_regiontype_from_id(st, RGN_TYPE_HEADER);
+		if(art) art->prefsizey= ED_area_headersize();
+	}		
+}
+
 /* make this screen usable */
 /* for file read and first use, for scaling window, area moves */
 void ED_screen_refresh(wmWindowManager *wm, wmWindow *win)
@@ -1076,6 +1088,9 @@ void ED_screen_refresh(wmWindowManager *wm, wmWindow *win)
 		else
 			wm_subwindow_position(win, win->screen->mainwin, &winrct);
 		
+		/* header size depends on DPI, let's verify */
+		screen_refresh_headersizes();
+		
 		for(sa= win->screen->areabase.first; sa; sa= sa->next) {
 			/* set spacetype and region callbacks, calls init() */
 			/* sets subwindows for regions, adds handlers */