[cairo] integer world coordinate system

[M Joonas Pihlaja]

On Wed, 18 Aug 2010, M.R. wrote:

> Our application takes a multi-dimensional physical model of reality and
> "flattens" it into something that can be shown on a screen or printed
> page. We end up with large "poly-line" coordinate arrays. Memory
> is an issue.

Currently cairo stores paths internally as integers, so there's no 
memory penalty from using doubles at the API level.

[snip flattening procedure]

> This will yield a line that has used as few expensive computations 
> as possible, yet be rendered with maximum granularity the display is 
> capable of.

You're free to pass integers to the cairo API.  They'll first be 
converted into doubles and then back to integers internally by cairo.