On Wed, 2007-10-17 at 03:58 -0400, Bernardo Innocenti wrote: > For those of you complaining that taking screenshots > was slow... it seems there's not much we can do even > with Composite and the latest X server.
Well, last time I measured, it took 0.15s. to take a fullscreen screenshot on the xo. So we are not so bad. If with composition we can take the screenshot while the window is hidden (and before the window is iconified/unmapped), then we'll be able to take reliable screenshots without using much extra memory during a long period. Tomeu > -------- Original Message -------- > Subject: Re: Fast Screenshot without blocking X events > Date: Wed, 17 Oct 2007 09:34:53 +0200 > From: Michel Dänzer <[EMAIL PROTECTED]> > Organization: Tungsten Graphics > To: GORIN Guillaume <[EMAIL PROTECTED]> > CC: [EMAIL PROTECTED] > References: <[EMAIL PROTECTED]> > > > On Tue, 2007-10-16 at 11:00 +0200, GORIN Guillaume wrote: > > > > -I don't want that all events on X are waiting in a stack, or something > > like this. Actually when capturing (using XGetImage) i can't continue to > > move window. It's why I suppose there is a stack of X events, that wait > > while capturing. Is it true? (If someone can tell me where to find > > informations about that. Xorg Wiki didn't help me). > > Yes, as the X server is mostly single threaded, event processing is > probably delayed while a request such as GetImage is being processed. > > > > I'm able to take screenshot in 3200x1200 in the framebuffer, but it > > takes 2.8 seconds. It's too long for me. I suppose there is a stream > > from X to the framebuffer, it's why reading is too long. > > No, CPU reads from video RAM can actually be that slow, especially with > AGP. It's possible to accelerate this using the GPU though. > > > > My questions are: > > -How X use the framebuffer /dev/fb0 when activated? > > The nvidia driver doesn't use it at all to the best of my knowledge. > > > -Can I take screenshot without blocking X events? > > If XGetImage is inadequate, the only alternative I can think of that > might be better is glReadPixels. > > > -Where can I get the picture of the screen before X send it to my > > geforce? (Is it possible?) > > Probably not, at least not without modifying the driver. > > > Hope this helps, > > > -- > Earthling Michel Dänzer | http://tungstengraphics.com > Libre software enthusiast | Debian, X and DRI developer > > _______________________________________________ > xorg mailing list > [EMAIL PROTECTED] > http://lists.freedesktop.org/mailman/listinfo/xorg _______________________________________________ Sugar mailing list [email protected] http://lists.laptop.org/listinfo/sugar
