context and core functions

QNX Newsgroups (Archives) qdn.public.ddk.graphics
1

hi all

i’m developing a driver for a CT65545 chipset, i done all the core function
to add hardware acceleration to svga driver, and i used the ffb library for
the context functions.

question 1:
from the point of view of the hardware acceleration, i must add the context
function or the ffb library call my core function when needed?

question 2:
in set_mode function what is the meaning of the surface structure passed? my
driver must use or write this data?


bye
donCiccio

2

donCiccio <donCiccio@hotmail.com> wrote:

hi all

i’m developing a driver for a CT65545 chipset, i done all the core function
to add hardware acceleration to svga driver, and i used the ffb library for
the context functions.

question 1:
from the point of view of the hardware acceleration, i must add the context
function or the ffb library call my core function when needed?

You get a pretty decent level of acceleration by only implementing
the core functions. Typically, io-graphics will call in through
the context function. If the context function has not been
accelerated by the driver, the ffb lib will detect if it is a
“simple” case and call a core function to perform the draw operation.

question 2:
in set_mode function what is the meaning of the surface structure passed? my
driver must use or write this data?

While the physical display resolution is either passed via the
disp_crtc_settings structure (generic mode) or is implicit from the
mode number, the virtual display resolution is passed via this surface
structure. If the driver supports virtual panning, it should use the
width, height and stride members of the surface struct to set up
the display.

bye
donCiccio

3

“David Donohoe” <ddonohoe@qnx.com> ha scritto nel messaggio
news:acek6u$5o3$1@nntp.qnx.com…

… If the context function has not been
accelerated by the driver, the ffb lib will detect if it is a
“simple” case and call a core function to perform the draw operation.

since this is my case, what fall in simple case and what no?
i need to speed up graphics output, what you suggest me to do?



bye
donCiccio