[OpenJDK 2D-Dev] How to determine if SurfaceType supports transparency?

Jim Graham Jim.A.Graham at Sun.COM
Sun Jun 7 21:04:29 UTC 2009

That isn't currently possible, but it sounds like a useful thing to add. 
  One problem is that there are some types that know that they have 
alpha, others that know that they do not, and still others which are too 
general and may have alpha or may not, so how do you encapsulate that 
information in a query?

For example, IntArgb does have alpha, IntRgb does not, but AnyIntDcm may 
or may not have alpha.

If we simply have ST implement Transparency then I suppose the types 
that are too general could simply return "Translucent" in order to avoid 
the promise of opacity.  It's the "safe" answer since Translucent 
doesn't guarantee that the pixels themselves will not be opaque - just 
that they have the option to be non-opaque...


Clemens Eisserer wrote:
> Hello,
> Is it possible to determine wether a SurfaceType does support transparency?
> I know its possible with SurfaceData, but I need to know at
> loop-registerion time where I only have access to SurfaceTypes of
> course.
> Thank you in advance, Clemens

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