Added the radius attribute to the point light

[Jose' C. <cru...@ce...>]

After several tries I've decided to not create an spherical light, =20
but just add the possibility of store the radius in the existing =20
point light...

so I've added two functions in the Quesa API:

Q3PointLight_SetRadius
Q3PointLight_GetRadius

using this functions you can still use the old point light, and the =20
renderers that not support spherical lights can just ignore the =20
radius...

I've also updated RayShade to use the radius, unfortunately there's =20
some problem in the antialiasing code and the result is not so good =20
as we expect, but worth testing nonetheless.

I'd choose to not use a property to make the radius an integral part =20
of the point light.


Pax et Bonum

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