RFR: 8217472: Add attenuation for PointLight [v5]

[Kevin Rushforth]

On Fri, 7 Aug 2020 22:30:39 GMT, Kevin Rushforth <kcr at openjdk.org> wrote:

>> The only impact this has is that the range will be maximal instead of 0. When these reach the shader, they will run the
>> lighting computation as opposed to skipping it. I'm not sure if this will have any performance impact though.
>
> In that case, it seems like a generally useful optimization (not just at initialization) to send down `maxRange` as 0
> whenever `ca`, `la`, and `qa` are all at their default values.

Actually, my above comment is wrong. A `maxRange` of 0 will effectively disable the lighting, even in the case whether
the other three values are 1, 0, 0. So `maxRange` should be set to `Float.POSITIVE_INFINITY` (or else just use the
default constants).

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PR: https://git.openjdk.java.net/jfx/pull/43