Thanks for the info Ilyes, that's generally what I expected and wanted to confirm. This approach makes it much easier for existing applications and especially ones with custom content/images for each supported resolution.
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. 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)? 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
