On Tue, 2002-11-05 at 04:10, Henric Andersson wrote: > > > Shouldn't it read 0.4 ? Also, the bufferflipping seems to be totally > > > messed up. Hard to describe but it seems like the changes made > > > doesn't always carry over as they did when using VESA. > > > > it's considered unstable, experimental and unfinished for a good > > reason. We'd be happy if this could improve but we only have limited > > resources and will need your help. > > I guessed as much :) > > Anyway, after doing some testing, this is what I found ... > > Case 1: Using savage framebuffer (with or without acceleration or DirectFB > gfx driver) > - Draw vertical line > - Flip buffer > = The vertical line is visible > - Draw horizontal line > - Flip buffer > = Horizontal line is visible (no verical) > - Draw a circle > - Flip buffer > = Vertical line and circle is visible but not horizontal > > Case 2: Same procedure but with vesa framebuffer: > - Draw vertical line > - Flip buffer > = The vertical line is visible > - Draw horizontal line > - Flip buffer > = Horizontal and vertical line is visible > - Draw a circle > - Flip buffer > = Vertical & horizontal line aswell as the circle is visible > > Is case #1 correct or case #2? I'd stipulate case #2 :) But since I'm no > longer sure, I need to verify this with someone who knows the innerworkings > of DirectFB and framebuffer a bit better than me. > > No other artifacts (like this) appears when using the console or mplayer > with fbdev as output. I'm running DirectFB 0.9.14 (release) and kernel > 2.4.19 > > /Henric
I think case 1 and case 2 are both correct depending on the setup. Case 1 is true if: a. fbdev supports pan_display; and b. frontbuffer and backbuffer are both in video memory. Ie you draw to backbuffer, then flip. The backbuffer is now the frontbuffer which does not contain the horizontal line, so your next draw is to an empty buffer. Case 2 on the other hand is true if: a. frontbuffer is in video memory and backbuffer is in system memory. buffer flips in these case is just 'copy contents of backbuffer to frontbuffer'. b. both buffers are in video memory, but fbdev does not support pan display. In this case, flips are done by using the copy command, or. What I'm not sure off is which should of the 2 cases should be correct behavior. Tony > > > > -- > Info: To unsubscribe send a mail to [EMAIL PROTECTED] with > "unsubscribe directfb-dev" as subject. > -- Info: To unsubscribe send a mail to [EMAIL PROTECTED] with "unsubscribe directfb-dev" as subject.
