Hi, > It does mean however though that the DFB core or systems drivers will need to > perform blits for the downscaling when > Flip/FlipStereo is called for display layers that do not support > DLCAPS_SCREEN_SIZE and DLCAPS_SCREEN_LOCATION > caps (arbitrary scaling). And that will require management of additional > hidden surface buffers to hold the actual flipped > side-by-side/top-bottom merged buffer.
Yes. An hidden double buffered bitmap for L/R composition - flipped every VSYNC (at worst case, fast animation). > BTW: For side-by-side/top-bottom, is it correct that the color and > transparency of the pixels between the left and right frames > should be transparent black (since I see no way to set this property > per-display layer) and thus that the actual opaque > background color comes from the associated mixer configuration > (DFBScreenMixerConfig::background field)? Yes, the graphics layer should have an alpha channel anyway. Clearing it before rendering w/ (0, 0, 0, 0) is just natural. -Ilyes > > Thanks, > Timothy > > -- > > Timothy Strelchun > Software Engineering > NTG Service Provider Division (formally DHG) > Intel Corporation > >>-----Original Message----- >>From: Ilyes Gouta [mailto:ilyes.go...@gmail.com] >>Sent: Friday, November 04, 2011 4:24 AM >>To: Strelchun, Timothy >>Cc: directfb-dev@directfb.org >>Subject: Re: [directfb-dev] Stereoscopic display layer handling >> >>Hi, >> >>> When running at say 1080p and the framing is side-by-side or >>> top-bottom, are the contents of all active display layers surfaces >>> expected to be automatically downscaled by half? >> >>Yes. The hardware would take care of that. >> >>> If so, does all of the active display layers being >>downscaled include >>> those configured with DLOP_LR_MONO and DLOP_STEREO, as well as ones >>> without either flag? >> >>The one without (if any) would just need to be duplicated w/o >>applying any horizontal shift (0 parallax). >> >>> What about if the application wants to handle things more >>efficiently >>> and configure the layer at the appropriate half size, thus only >>> rendering to the actual half sized surface (of course just when the >>> display mode is side-by-side or top-bottom)? Is this possible? >> >>But then what about legacy applications that expect to just >>still render @ 1920x1080 (so the primary surface is expected >>to be @ HD). 32 MB of VRAM is the least amount required for >>stereoscopy :) Yes, that's too much. >> >>-Ilyes > _______________________________________________ > directfb-dev mailing list > directfb-dev@directfb.org > http://mail.directfb.org/cgi-bin/mailman/listinfo/directfb-dev > _______________________________________________ directfb-dev mailing list directfb-dev@directfb.org http://mail.directfb.org/cgi-bin/mailman/listinfo/directfb-dev
