Object placed behind layers of transparent surfaces is not visible when rendered
Article needs peer review
Symptom
Multiple objects are positioned in such a way that each object is contained one inside another (e.g. similar to a Russian doll). All the objects' materials are 100% transparent, except for very last object located at the center of the group, which is opaque.
Example (before)
<A target=_blank href="/support/xsi/private/kb/images/1sphere.jpg"><A href="/support/xsi/private/kb/images/1sphere.jpg">/support/xsi/private/kb/images/1sphere.jpg</A></A>
Cause
Both the Raytracing Depth and Raytraced Refraction values are not set to high enough values. In other words, the rays are not reaching the desired object located behind the layers of transparent surfaces. Therefore, this object will not be visible in the rendered result.
Solution
Simply increase the Raytracing Depth: Refraction and Maximum Ray Depth values until the object is visible in the rendered result.
Example (after)
<A target=_blank href="/support/xsi/private/kb/images/2sphere.jpg"><A href="/support/xsi/private/kb/images/2sphere.jpg">/support/xsi/private/kb/images/2sphere.jpg</A></A>
More information
Raytracing Depth
Ray Depth refers to the number of times that a ray is reflected or refracted during the raytracing process. Each refraction or reflection of a ray creates a new branch in a ray tree.
Tip: Use higher values for a more accurate image or lower values for faster rendering.
Reflection</B>: Sets the maximum number of a ray's reflective branches in a scene. For example, in a totally reflective scene, the ray continuously bounces around in the scene creating an infinite number of branches. This option lets you set an upper limit on these calculations.
<B>Refraction:</B> Sets the maximum number of times a ray can be refracted in a scene.
<B>Maximum Ray Depth</B>: Sets an upper limit on the sum of a ray's reflections and refractions.
References
Rendering
Chapters 3 : Rendering Options : Raytracing ( page 62 )
&
Shaders, Lights & Cameras : Chapter 3 : Material & Texture Basics
Tips, Optimizing & Troubleshooting ( page 114 )
Applies To: XSI 1.0,XSI 1.5 on NT,Win2K,Irix
Posted: 6/25/2001
