Messages in this thread | | | Date | Tue, 28 Dec 1999 11:12:10 +1000 (EST) | From | Ben Williamson <> | Subject | Re: Announce: DinX windowing system 0.2.0 |
| |
On Mon, 27 Dec 1999, Alan Cox wrote:
> > Right. Just to clarify, performance is currently horrible on PC hardware > > because we read (memmove) from the framebuffer a lot when dragging windows > > around. And it seems PC hardware does this really slowly. > > All normal graphics hardware has this property. You can't do posted reads > but you can do posted writes.
We've just switched to redrawing by default, rather than memmoving. Things are much, much faster on PCs now. I'll post an announcement of a new version as soon as I can get it uploaded.
> > Right. The idea is just to take clipping and blitting out of the server > > process and put them in the kernel, to avoid lots of context switches and > > big complex buffering code. > > If your gui system is doing batching of commands this makes no difference. > Its one of the things X11 showed that was quite suprising.
My understanding is that's certainly true for performance, but not memory usage and code size/complexity. My board only has 2MB.
I'm sure I'm making lots of mistakes that have been made before, but that's okay - I'm learning lots from doing it. This is a project I've wanted to do for ages, and I quit my job so I could spend time on it. And I really do think we can build something smaller, simpler and faster than nanogui. We'll see.
> > each, so the complexity of the visible area goes on the stack. Now, how > > much stack space does the kernel have? :) > > Bang...
Also fixed in the new version, the clipping algorithm now uses a stack structure allocated with kmalloc. Thanks to everyone who provided advice on this. I now understand very clearly why a dynamically growing stack area would make dealing with races awful tough. :)
Cheers,
- Ben.
------------------------------------------------------------------- Ben Williamson benw@pobox.com http://www.pobox.com/~benw/
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
| |