Frend Patrick-BPF005 wrote: > Just starting to look ad DirectFB, and have a question about the > relationship between IDirectFBScreen, multi-headed setups and multiple > frame-buffers. > > As I understand it, a DirectFB session can only access a single > frame-buffer? But you could run multiple DirectFB sessions, each > accessing a different frame-buffer.
Yes. > However, IDirectFBScreen seems to imply that DirectFB could support a > multi-headed display system IF the frame-buffer driver supports multiple > screens within the same frame-buffer? Exactly :) > If this is true, what are the pre-conditions that need to be met for the > framebuffer driver to support multiple screens? It just needs to implement basic functionality to show graphics on one layer of one screen. That's where the Linux console will be shown. DirectFB uses this implementation via ioctls to control the primary layer. Any additional layers or screens are added by the graphics driver if there's any. You can also decide to provide all layers on your own, not using the framebuffer interface. Anyhow, your single framebuffer device should provide enough memory for all layers on all screens. The user space driver should be able to talk to the hardware or another kernel module. If you're just setting some MMIO registers, you can use the builtin MMIO mapping feature [tm] of the framebuffer device. -- Best regards, Denis Oliver Kropp .------------------------------------------. | DirectFB - Hardware accelerated graphics | | http://www.directfb.org/ | '------------------------------------------' _______________________________________________ directfb-dev mailing list [email protected] http://mail.directfb.org/cgi-bin/mailman/listinfo/directfb-dev
