RFR: 8234920: Add SpotLight to the selection of 3D light types [v15]

[Ambarish Rapte]

On Fri, 11 Jun 2021 11:38:33 GMT, Ambarish Rapte <arapte at openjdk.org> wrote:

>> Hello Nir, could you please merge this branch with latest master.
>
>> I think so too. Did you test on Win? Does @arapte want to test these functions too?
> 
> Yes, I shall test too, and get back to the review...

> @arapte If you run the test app without the spotlight patch, but with the attenuation patch, does it work better?

Here is what I tried,

1. Run existing AttenLightingSample without this PR changes. The sample works as expected.
2. Run existing AttenLightingSample with this PR. The sample does NOT work as expected.
2.1 If any one light is turned on then the output is same as the screenshot I shared in previous comment.
2.2 If two or three lights(including red light) are turned on then the red light does not illuminate correctly. (Observe the following screenshot, there are some yellow colored pixels in red light color)

![image](https://user-images.githubusercontent.com/11330676/122015572-d6320180-cddd-11eb-8421-158618d64cd4.png)




So looks like, the issue occurs only with the changes in this PR.

-------------

PR: https://git.openjdk.java.net/jfx/pull/334