RFR: 8318985: [macos] Incorrect 3D lighting on macOS 14 and later

[Kevin Rushforth]

On Wed, 23 Apr 2025 12:31:49 GMT, Ambarish Rapte <arapte at openjdk.org> wrote:

>> When no specular color is set while rendering 3D primitives, 0.0 specular power value is used by default in our shaders.
>> When same specular power value is used in pow() function in shader it results in undefined behaviour as mentioned at : https://registry.khronos.org/OpenGL-Refpages/es3.0/html/pow.xhtml
>> 
>> By default specular power value should be 32, so now the specular_none.frag file is updated to use this default value to make sure we don't see 3D lighting issues on some platforms. This change is tested with Ensemble8 and fx83dfeatures and i don't see any regressions.
>> 
>> Also one of our system test _PointLightIlluminationTest_ used to fail because of this issue. It passes now with this update and it is re-enabled.
>
> @jayathirthrao 
> Does this change has any effect on Linux platform ?

Reviewers: @arapte @kevinrushforth

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PR Comment: https://git.openjdk.org/jfx/pull/1791#issuecomment-2824284564