If an object must cast a shadow
on another one, it may happen that the shadow is unwedged this effect
doesn't appear when there is a minimum distance between the objects . It
becomes ennoying when an intersection must be done. This effect is only
visible on the intersection boundaries, and only with a centring which
line of sight shows this boundary.
Let's imagine
a basic condition : a spotlight, and 2 planes that are cutting themselves
at right angle.
You can notice that the more
the light incidental angle is great the more the light is "smudgy" at the
planes junction point . fortunately to settle this problem, there is a
method : You have to carefully calibrate the distance between two elements
wich determine the Buffer shadow boundaries of the spotlight: ClipSta
and ClipEnd.
Several tests are necessary there is no
recipe. You can notice that tightening too much the distance creates a
very bad effect on one of the object because it goes out of the shadow
buffer.
However you can significantly reduce this
effect but it remains a watered effect.
It's also possible to eliminate this watered
effect in increasing the "Samples" value.
