[PATCH] mi: removed the invisible cursor sprite; use NullCursor instead.

[Oliver McFadden]

On Tue, 2010-05-18 at 22:38 +0200, ext Jamey Sharp wrote:
> For the xfree86 DDX, if hardware cursors are used, the driver is
> required to provide a HideCursor function, which will be called
> instead of trying to set a null cursor. I think software cursors are
> already safe. The other DDXes also look safe, as far as I can tell.
> 
> I think UnrealizeCursor is never called on a null cursor. As far as I
> can tell, it's only called from FreeCursor and
> RealizeCursorAllScreens, and I'm confident both of those won't pass
> null. So I'd drop the hunk changing miPointerUnrealizeCursor.

Ok, makes sense.

> If this patch is correct, I think you should also drop the hunk
> changing miPointerRealizeCursor, and instead quit calling
> RealizeCursor from CursorDisplayCursor. As far as I can tell, there's
> no reason to realize a null cursor. I think everything that handles
> null cursors doesn't rely on any setup in RealizeCursor, and treats
> them as empty cursors.

Alright, I'll roll another patch and check it.

> 
> With those changes, I'd be fairly confident that this change is safe.
> 
> Hey, nothing ever wraps miSpriteCursorFuncRec. Can somebody tell me if
> there's some reason not to kill the function pointer tables there and
> just call the midispcur.c functions directly from misprite.c?

I saw you've already cleaned these up; I was a bit behind on xorg-devel
reading.

-- Oliver.