Hmm...going further, the only way I see to deal with this at the nxgl
layer above the lcd structure itself is to add a nx_redraw with
corresponding NX_EVENT_REDRAWING/NXEVENT_REDRAWN event callbacks, but
that makes the nxgl layer device-aware...I don't see how it can't be
really, these things are pretty different to traditional LCDs. For the
case of the lcd nx_updatedisplay member not being present I would just
return the NXEVENT_REDRAWN immediately so everything would remain
back-compatible.
I don't really see any way to avoid this. Greg, any suggestions for a
better approach?
Regards
DAVE
On 17/12/2019 10:56, Dave Marples wrote:
Folks,
I've implemented an ePaper driver under nxgl, but as some of you are
probably aware there needs to be an explicit redraw request to update
an ePaper display.
I'm not quite sure how to do that under nxgl as normally it would be
driven automatically. It also takes a fair bit of time (~14 seconds
for a colour display) during which period access to the ePaper is
'locked out' so the application really does need to be aware of what
is going on.
My intention is to add an nx_updatedisplay() API...but is there a
better, or already available, way to do this? It could be done via a
call to nx_setvisibility on the background window I guess, but
personally I don't like overlaid semantics like that...
Regards
DAVE
