Template:Fusion 6 ObjVisibility
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Visibility
If the visibility checkbox is not selected, the object will not visible in the display views, nor will it be rendered into the output image by the Renderer 3D tool. A non-visible object does not cast shadows.
If the Unseen by Cameras checkbox is selected, the object will be visible in the display views (unless the Visible checkbox is turned off), except when viewed through a camera. The object will not be rendered into the output image by the Renderer 3D tool. Shadows cast by an Unseen object will still be visible when rendered by the software renderer, though not by the OpenGL renderer.
Use these options to cull (eliminate) rendering and display of certain polygons in the geometry. If Cull Back Face is selected, all polygons facing away from the camera not be rendered, and will not cast shadows. If Cull Front Face is selected, all polygons facing towards the camera will likewise be dropped. Selecting both checkboxes has the same effect as deselecting the Visible checkbox.
In Fusion 5 transparent pixels were rejected by the SW/GL renderers. To be more specific the SW renderer rejected pixels with R=G=B=A=0 and the GL renderer rejected pixels with A=0. This is now optional. The reason you might want to do this is to get aux channels (eg. normals, z, UVs) for the transparent bits. For example, suppose in post you want to replace the texture on an 3D element with a texture that is transparent in certain areas with a texture that is transparent in different areas, then it would be useful to have transparent bits set aux channels (in particular UVs). As another example suppose you are doing post DoF... you will probably not want the z channel to be set on transparent areas as this will give you a false depth. Also keep in mind that this rejection is based on the final pixel color including lighting if it is on. So if you have a specular highlight on a clear glass material, this checkbox will not affect it.