Freetype-based text rendering and font discovery

[Michael Goffioul]

Hi,

I'm currently working on text rendering in the OpenGL backend, using
freetype. I have a draft working version that contains enough to render
tick labels, axe labels and title, as well as basic text objects
(90x-rotated, no background, no border, no margin...).

But before commiting anything, I'd also like to add basic font discovery
mechanism. Up to now, I'm using an hardcoded TTF font that will only
work under Windows.

I'm thinking about using fontconfig, which I guess is widely spread
in UNIX environment. To make it simple in the configure script, I'm
thinking about using pkg-config to find out fontconfig compilation flags.

Would these added dependencies be acceptable?

Michael.