Frustrum culling in Virtual Production

Frustrum culling is a Real-Time Engine term in filmmaking. In virtual production, the nuances of this term take on special meaning. Here, we break down the definition to give you a starting point.

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Basic Definition:

What is Frustrum culling in virtual production?

It’s the process of removing objects or reducing rendering quality for areas that lie outside the inner frustum since they are not directly visible to the camera. It helps keep your computer's performance up and reduces lag while allowing you to focus on those elements that will actually be seen by the audience. 

When it comes to deciding which objects need to be removed or adjusted, it is important to consider both the type of shot being filmed and what items will be viewed from within the inner frustrum. For example, if you have an outdoor scene with several trees in view, then only those trees that appear within the frame should have detailed renderings applied to them; any trees outside the frame can have a reduced level of detail. The same logic applies to other aspects of the scene such as buildings, vehicles, props, and background elements. 

Frustrum culling is also useful during pre-production as well. By utilizing this technique, directors and VFX supervisors can plan shots accordingly to ensure all necessary details are included within the confines of the inner frustum while eliminating redundant elements outside of the frame. In other words, it’s a great way to save time and money by limiting unnecessary renderings and effects work.