[cairo] OpenType font variations and cairo

[Adrian Johnson]

On 14/09/17 07:11, Matthias Clasen wrote:
> Over the last few days, Behdad and I worked together on supporting
> OpenType font variations in the Linux text rendering stack. This
> requires small additions to pango, fontconfig, and ... cairo.
> 
> The cairo patch is simple and ready (i'm still debugging some issues on
> the pango side).
> 
> It adds a new member to the font options struct, a string which contains
> the font variation settings.
> 
> 

> + * Sets the OpenType font variations for the font options object.
> + * Font variations are specified as a string of the form
> + * AXIS1=VALUE1,AXIS2=VALUE2,... with each AXIS being a 4 character
> + * tag naming a font variation axis such as wdth or wght, and each
> + * VALUE being a floating point number.

cairo_tag_begin() attributes uses space instead of comma to separate a
list of key=value. Maybe we could try to be consistent?