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Subject: Re: Re[2]: Multi-display (lcd remote) design discussion

Re: Re[2]: Multi-display (lcd remote) design discussion

From: XavierGr <>
Date: 2005-08-11

Well I have been working for the remote for some time, and due to lack of
programming skills I headed for a cheap mirroring trick. If you are
interested I have uploaded a patch of my work in MisticRiver

About the patch:
Well the patch is based upon a single trick that adds an lcd_remote function
for every lcd_ in tree.c, wps-display.c and wps.c. Though things are not so
simple. The good thing is that the whole lcd_remote function pallette is
ready and working. So no low-level code must be written.
To minimize bugs in my patch I had to make many defines for the remote and
new functions. (Progress bar function, scrollbar function, e.t.c)

Also I had to make a whole set of settings for the remote for every option
refering to the main display. All these options are under General
Settings->Display->Remote-LCD Settings, until they are sorted out.

Problems: While the patch works "nearly" perfect and I could make it work
that way for every menu, there is a major bug that ruins everything (and
thus one of the reasons for a different approach).
In tree.c there is a function "recalc_screen_height" that returns the height
of the available screen space. As you can see this functions is repeatedly
called during the program by the tree_max_on_screen variable. So in the end
the remote screen (because has lower height) hides some entries in the
To avoid this a made an option in the settings which will let you choose
which is your primary screen remote or main. Enabling this option will make
things for the remote render okay but the tree in the main unit will be cut
in half.

I would be willing to try to make a better implementation for the remote but
I don't think I can do that alone. The tree.c and wps.c code is vast and
very difficult to understand all of it.
So if anyone is interested about it and has the skills, there are patch,
build, and sources on the link I gave, e-mail me and I would be more than
happy to help, or get helped for it.

On 8/11/05, Daniel Stenberg <> wrote:
> On Wed, 10 Aug 2005, Geoff Smith wrote:
> > I appreciate that the screen size is different and this will make some
> > things difficult. From a user (rather than developer) point of view I'd
> like
> > to see a second .wps file for the remote. How difficult is everything
> else?
> > The browser and the menus are effectively the same, a list with an item
> > highlighted, on the remote you'd just see less of the items surrounding
> the
> > currently selected one.
> I don't think any of this is hard by definition, it is just work that
> needs to
> be done that takes changing quite some code and some new code to be
> written.
> That takes time and energy.
> I'm behind the idea that having the code turned into suitable functions
> and
> have the code "sync" both displays is a good start, and then we can do the
> two
> screens doing different things implemented later on.
> --
> Daniel Stenberg -- --
> _______________________________________________
Received on Thu Aug 11 14:49:34 2005

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