[Pixman] Gradients patches

[Andrea Canciani]

On Tue, Oct 12, 2010 at 1:09 PM, Soeren Sandmann <sandmann at daimi.au.dk> wrote:
>...
>
> It would be useful for someone to update the Render spec to say that
> the radials are PDF Type 3 Shadings, defined in section 8.7.4.5.4 of
> the PDF specification, and delete the stuff about the circles being
> contained in each other.

I'm pinging the ML about this again, because I would like to add
a couple of facts.

Cairo has been abusing Render radial gradients by requesting their
rasterization even when the "outer" circle did not contain the "inner"
circle. The specification explicitly disallows this, but the server
doesn't return an error and draws the gradient, instead.

The change suggested by Soeren seems to be very appropriate
to make specification and implementation more consistent.

Additionally the gradient definition did not change for the values
allowed by the specification, so extending the range of valid values
should be pretty safe.

Andrea Canciani