FYI: 8243508: Update alpha blending and compositing functions

[Alexey Ushakov]

> On 28 Apr 2020, at 02:07, Kevin Rushforth <kcr at openjdk.java.net> wrote:
> 
> On Mon, 27 Apr 2020 22:21:06 GMT, Alexey Ushakov <avu at openjdk.org> wrote:
> 
>> Corrected FLT_LT and FLT_GE macro
>> Fixed test/jdk/java/awt/image/DrawImage/IncorrectUnmanagedImageRotatedClip.java failure caused by fix of 8243505
> 
> src/java.desktop/macosx/native/libawt_lwawt/java2d/metal/MTLComposite.m line 154:
> 
>> 153:     }
>> 154:     return isSrcOpaque;
>> 155: }
> 
> Thanks for fixing this. Btw, I think this still needs to be looked at. Unless there is a case I haven't thought of,
> both of `extraAlphaIsOne` and `isSrcOpaque` should be used, or else neither of them should.

Yes, I’ll look at it more closely after fixing AA clipping problem.

Best Regards,
Alexey

> 
> -------------
> 
> PR: https://git.openjdk.java.net/lanai/pull/40