Rendering Occluded Objects in 3ds max

Rendering occluded objects can help you create 3D effects when you later composite the images. The following G-Buffer channels can have extra 'layer' information when you render occluded objects:

• Z-buffer
• Normal
• Non-Clamped Color
• Coverage
• Node Render ID
• Color
• Sub-Pixel Weight
• Sub-Pixel Mask

Several combustion features use this extra information. Although the information for these channels is called a layer in 3ds max, it is not related to layers in a composite.

When a 3D scene contains objects that occlude each other, a 3D Post filter may need information about what is behind each object. For example, if you remove a tree from a forest scene using G-Buffer Extract, you want the rest of the forest to appear behind it, not a black occlusion.

To set an object to render extra information when rendered:

1. In 3ds max, select and right-click the object, then choose Properties from the menu that appears.
2. In the Object Properties dialog, enable Render Occluded Objects.

For example, you can have more than one Z buffer layer. The first layer shows the Z values of the first objects you see in the scene. Where objects are hidden, the second layer shows the Z values of the objects behind the ones in the first layer. This continues until you reach the 'back' of the scene.