I'm trying to create semi-transparent objects which cast shadows whose intensity depends on the thickness of the the object itself. A simple example would be a wedge shaped object which casts a light shadow on it's thin side, which gradually becomes darker as the thickness increases. I'm guessing it would be similar to adding an adsorption effect to the light ray. I tried using the normal blender render but had no luck. So I tried adventuring in the cycles and nodes, playing with the light path is shadow ray. But again to no avail. I suppose I actually have to change something in the receiving object but can't figure out what. Does anyone have an idea of how I could achieve this effect
You can use volume shaders to achieve a shadow that varies with the thickness.
I used the light path 'is shadow ray' to 'disable' the shadows of the glass shader, and to set to 0 the density of the volume inside the glass, although this is actually not necessary.
The thickest part of the model is 1 BU (1 meter).
Bear in mind that this is not realistic.