9.5.2

712 • CHAPTER 13
RENDERING • RENDER SETTINGS • 713
Ray Depth
The Ray Depth determines how many transparent objects (or areas made invisible using the alpha
channel) can be penetrated by the renderer. The lower you set the Ray Depth, the fewer the number
of objects that can be seen through. Those areas that cannot be penetrated are rendered black.
A Ray Depth of 1 means that calculations are nished for a pixel once its ray hits something in the
scene. Transparencies and alphas therefore will not be visible. A value of 2 means that after a ray has
hit a surface a second ray is calculated for the transparency. The higher the Ray Depth, the further rays
are followed into the scene and the results rendered. The results shown above contain transparencies
and alphas and have been rendered with ray depths of 2, 4 and 8. You can enter values up to 500.
Reection Depth
When a ray is sent into the scene, it can be reected by reective surfaces. With certain arrangements,
e.g. two mirrors opposite each other, it is possible that a ray will be reected forever, trapped between
the mirrors, and the raytracer would never nish rendering the picture. In order to prevent this, you
can set the maximum number of reected rays.