> > > I have a 2 MB video buffer, only about 200k is used for 
> front buffer
> > > (and another 200k for back buffer).
> > > 
> > > I want to put a bunch of various images in the offscreen 
> > buffer to be
> > > blitted quickly for screen draws.  
> > > 
> > > At program startup, I'm creating a surface for each image 
> > and rendering
> > > to it, but it would appear that these are going into system 
> > memory, not
> > > video memory since the blit functions of these images don't 
> > work.  If I
> > > set these "cache" surfaces to videoonly, then they end up 
> > rendering on
> > > my main video area.
> > 
> > That should not happen. DSCAPS_VIDEOONLY is the proper way to 
> > do what you 
> > want. What driver are you using?
> > 
> > If you don't specify DSCAPS_VIDEOONLY / DSCAPS_SYSTEMONLY 
> > DirectFB will 
> > decide where to place the data. It may also swap them from 
> > one memory pool 
> > to the other during normal operations. All of that is completely 
> > transparent to the application.
> 
> That explains a few things.  In the past, dfb has decided to 
> put them in the video memory, but I never knew why.  I will 
> specify the video only option.  What is means is that I need 
> to go fix my custom driver (for epson s1d13506).  
> 
> I'll probably be posting back to figure out what is wrong 
> with my driver.


Ok - here are my further questions:

1) Do I need to have the InitLayer function written for this driver, or can I use the 
Fbdev one?  Same question for SetConfiguration...
2) This thing is not using any windows or video or anything.  Just a frame buffer to 
write to and then flip.  I'm putting stuff into the offscreen (non-backbuffer) area, 
and building up the screen, then fliping.  Can I safely ignore layers, windows, etc?  
Just define a primary surface for the display, and then define a surface (or surfaces) 
for offscreen to pre-render things to?  Then blit from the pre-rendered surfaces to 
the primary surface?

I though I had all this figured out and things seemed to be working, but now nothing 
seems to work right.  Any help with my misconceptions would be greatly appreciated.  

-David
 


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