LCDproc development and user support list

Text archives Help

[Lcdproc] bounding box

Chronological Thread 
  • From: dglaudemailing AT (David GLAUDE)
  • Subject: [Lcdproc] bounding box
  • Date: Tue Jul 29 14:12:01 2003

Joris Robijn wrote:
> I've had some discussions with Michael Frase about the bounding box and
> the rendering process. Michael said he wanted to work on the rendering
> process, and to enable him to do that I need to get the bounding box
> function into the API. It would become:

What hardware is Michael using for the test?

That or those driver need to be adapted ASAP.

In order to avoid a big period of time where 0.5 will be broken for most
driver, it would be nice to freeze and make downloadable a nightly build
so that if CVS or new nighlty build are broken, it is still possible to
have one of the latest working 0.5 (without that nice feature).

> int _set_box (int left, top, right, bottom);

Is this a "protection" box that garanted I can not write outside of
boundary box (nor above, nor below) but does not change the fact that
coordonate (2,4) is still the physical (2,4)?

Or is it a change of reference (left,top) is the new (1,1) or (0,0),
plus a protection so that no one access above (right,bottom) in the new
reference or (right-left, bottom-top) in the new reference.

Now how do we reset the _set_box to the default value?

Are the left/top/right/bottom included or excluded (is it [left,right]
or ]left,right[ or [left,right[ ...

Is it not a good time to choose between (0,0) or (1,1) to be the top
because it seems most driver do -1 or +1 when they receave parameter?

Is there any reason why this thing can not be done in central server
code? If it is only a filtering, then what is the problem.

Other option, if that filtering is possible to do without knowledge of
the driver internal, then a generic solution can be found for all driver.

> This area would from that moment on be the 'enabled area'. Only in that
> area placements of characters and icons would actually occur. Just like
> Adobe Photoshop does that :)

I don't know about Photoshop, maybe you are talking about a Gimp clone?
Is there a patent on that feature?

> I will also need to adapt drivers for this :( A side effect is that the
> drivers will then all check for wrong coordinates, preventing writes at
> wrong memory locations :)

The above might answer my previous question.

> If noone object I'll put it in tomorrow (yes I want to rush this a bit :)

Ok for the rush...

But a description of how it will work and how it worked before would
help the debate:


set_box (2, 2, 10, 3);
(and give the same result)

set_box (2, 2, 10, 3);
(print nothing on LCD)

[Warning, the above is an example of what kind of pratical explanation I
would like to understand, not the effect I assume]

Actually I take 2 weeks of vacation starting from friday, so it might be
short to adapt any driver I usualy care for. ;-)
Except if it is really rushed and exchange with my family 2 week without
laptop/internet against a night of LCDproc coding...


Don't let the computer/expert control the election
Information for Belgium in french:

Archive powered by MHonArc 2.6.18.

Top of page