standard soft_light shader

[jankin]

hello forum!

Well, recently, I have found out that something doesn't seem right with the standard soft_light shader for XSI. It seems that the visible area light intensity is computed wrong. The shader does not take the surface area factor of the area light into the computation. This means

http://xsi.jankin.com/dump/demo_01.jpg
In this image everything is alright. Nice reflections and nice light attenuation.

http://xsi.jankin.com/dump/demo_02.jpg
Now, if we enable the area light to be visible in the render the intensity of the disc is the same as the intensity of the light. Which is obviously to high.

http://xsi.jankin.com/dump/demo_03.jpg
I think that the intensity of the area light disc should be computed this way: light intensity / surface area of the light

What do you think about this? Am I correct?

[Saturn]

true soft_light shader isn't physically correct. You should use the physical_light shader.

you can find the shader here : http://www.tek2shoot.com