[cairo] API to set PostScript Language Level

[Behdad Esfahbod]

On Tue, 2007-09-18 at 18:07 -0400, Adrian Johnson wrote:
> The PostScript backend currently generates Level 2 PostScript.
> In order to support Level 3 features such as gradients an API function
> for selecting the LanguageLevel is required.
> 
> The following API is based on the SVG restrict_to API. A patch to add
> this API is attached.

Looks generally good, and like what I had in mind.  Please also update
ROADMAP.

What's missing / needs discussion is:

  - For both SVG and PS, do we need to add a getter function for the
level of a surface?

  - What is the default level?  How does it change in the future? How
can a user set it to latest supported version?  Or do we list versions
in any specific order?  I'm just trying to make sure that level-agnostic
applications don't end up generating poor PS/SVG just because they
didn't set the level.

Cheers,
-- 
behdad
http://behdad.org/

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