> > This is getting stranger still... It seems that the FlipBuffer function in > > the savage driver isn't used. Instead, it falls back to the generic > > framebuffer thingy. Whats more, savagefb has primary and a secondary layer > > ?? And only the primary layer is used (it seems) and that would explain some > > of the strange behaviour. But not all... far from it. The secondary layer > > seems to "lock" the user into 640x480 display? Go figure.... > > > > Does someone know what all this means? The source isn't exactly filled with > > comments :( > > > The primary Layer is the framebuffer. Other layers are extras that are > not supported by fbdev, for instance Video Overlay.
Ah... well, that explains why I found it... started to get a bit confused especially since I couldn't find any documentation on this at all :) > So all DirectFB drivers will have a Primary layer, and the default flip > command is fbdev's pan_display, if supported. Which it is... the drawback of this is that any changes currently visible will disappear and be replaced with the new changes on the nonvisible buffer. It makes kinda sense now that I think of it (remembering the good old Amiga & AMOS Double Buffer command combined with Swap Buffer :)) So essentially, when the pan display command doesn't work, the emulation isn't correct since the display shouldn't be copied, it should be exchanged. This is truely a pain in the ------ since I now have to rewrite most of my program to work this way *DOH* ! > Other layers, because they are extras, need to have device-specific > hooks. In this case the FlipBuffer() function that you see is probably > for the Secondary Layer. Most of drivers that has a secondary layer > issues a dfb_surface_flip_buffers() before doing anything else. This > does _not_ call pan_display, but just swap the front and backbuffer > pointers. The actual flip will be done by the driver itself. So, the secondary layer cannot be used when running in framebuffer then? Or am I mistaken? /Henric - Beginning to see the light ;) -- Info: To unsubscribe send a mail to [EMAIL PROTECTED] with "unsubscribe directfb-dev" as subject.
