[mythtv-users] FAQ

[Steve Hodge]

On 10/9/05, Phill Edwards <philledwards at gmail.com> wrote:
> > The FAQ is right (except x and y are swapped, ie. x = horizontal res *
> > 0.254, y = vertical res * 0.254).
> >
> > The equation is:
> > xdpi = 25.4 * HR / W
> > where HR is the horizontal resolution and W is the width in mm (which
> > is what goes in the config setting).
> >
> > We want xdpi to be 100, so solving for W gives us:
> > W = HR * 25.4 / 100
>
> So how do you work out the horizontal resolution of your TV? Or is it
> the 800 in 600 x 800?

Whatever resolution you've got X set to, so yeah 800 if it's 800x600.
And you do the same thing for the height: H = VR * 25.4 / 100.

It's confusing because we're really not setting X up the way we're
supposed to. What X expects is the physical width so it can calculate
the real dpi based on the equation I gave first. Then it'll use that
dpi figure to pick fonts the to use. But that's all based on the idea
of a user sitting 30-50cm away from a monitor so it doesn't work well
for TV setups because it'll result in fonts sized appropriately for
some sitting 30-50cm away rather than 2+ metres or whatever. Net
result is fonts that are too small. To avoid this problem we're giving
X the width that would result in X calculating a dpi of 100 (which
gives fonts of the right size for the rest of the interface).

Steve