Issue with a Projection Layer Lamp

[Jonnee]

Today I created my very first projection light and I did exactly what the tutorial told me. But something went wrong:
When I moved the avatar inside of my defined area (Dist 10, Square Size 7, Energy 3, purple colour) I could see the created shadow texture there. But the purple light by itself was visible in the whole age, far outside of the defined range. In addition to that the avatar casted a new shadow also far outside of the range.
Anyone has an idea why the light of the area lamp was visible everywhere? I played alot with the values but could not find a way to turn it off.

[Paradox]

Be careful with Energy values, colour values are multiplied by the energy. So a white lamp (1.0, 1.0, 1.0) with an energy of 3 will actually output RGB 3.0, 3.0, 3.0. Uru behaves oddly with colour values larger than 1.0!

[Nadnerb]

this is because all the objects in your age are being affected by the layer lamp. You need to manually fix it so that only some objects are affected. Use lightgroups. This is on a full object basis though. The avatar is special in that it is only affected within certain bounds.

[Jonnee]

Thanks for your answers.
I did so and created a lightgroup for that area light and another group for the usual world lights. It works and looks fine.
(By the way: Do you know a short way to copy only my Shaders value "GR: worldlights" to 50 different objects?
Selecting these objects and pressing "Strg-C" doesn't help me, because I don't know what to choose to copy only that GR-value.)

But the avatar still causes that area light affected shadow everywhere in the world... How can I turn it off outside of the area?

[Christian Walther]

Be careful with Energy values, colour values are multiplied by the energy. So a white lamp (1.0, 1.0, 1.0) with an energy of 3 will actually output RGB 3.0, 3.0, 3.0.

Actually, for some reason, PyPRP multiplies the energy by 2, so that lamp would output RGB 6.0, 6.0, 6.0. That caused me quite some confusion when I was trying to figure out how the shading works recently – somehow my objects were lit too brightly in a peculiar way with a lamp energy of 1.0. It's not immediately obvious because there's a clamping step between vertex processing and fragment processing, so the texture doesn't appear too bright, only the underlying shaded vertex color (the existence of that clamping was the second thing to throw me off, it explains why vertex colors and texture colors are treated differently in areas where ambient + diffuse > 1). Moral of the story, now that I think I understand how the shading works: keep the lamp energy at 0.5 or below. (That in turn makes the dynamic shadows very weak, which I solved by hacking PyPRP to apply the multiplication by 2 for shadow strength too.)