[cairo] Fwd: Re: [Mesa3d-dev] more glitz points

Bill Spitzak spitzak at d2.com
Thu Apr 22 12:07:33 PDT 2004

On Thursday 22 April 2004 11:26 am, Carl Worth wrote:

> The "cairo way" of specifying an ellipse is usually to just provide a
> circle and a transformation. So perhaps David's "two ellipses" are
> actually just two circles modified by the same transformations.
> If so, the only distinction I see between that and the images you have
> is the presence of an inner radius, (which would presumably be treated
> with the same extend attribute as the outer radius).

The two nested circles can be done instead with a center point and having the 
color ramp be constant within a certain distance of the center. The center 
point would be at the same location inside the small circle that the small 
one is inside the big circle.

Modifying the color ramp would also solve the problem that the interpolation 
between the outer edge and point may not be what the user expects (ie it is 
not linear) in the offset examples when using the perspective transformation. 
I tried to compensate for this but I actually felt the non-linear 
interpolation looked a lot better and more consistent.

                   ,~,~,~,~ ~ ~ ~ ~
     /\_       _|_========___         Bill Spitzak
 ~~~/\/\\~~~~~~\____________/~~~~~~~~ spitzak at d2.com

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