Frustum in Virtual Production

Frustum 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 Frustum in virtual production?

The word 'frustum' is derived from Latin and means "a part cut off." In the context of virtual production, a frustum is an area in a virtual world that appears as a viewport to the camera. 

A key aspect of the frustum is that there are two separate frustums: an inner frustum and an outer one. The inner frustum moves in sync with the camera movement, while the outer frustum remains static so that lighting can remain consistent and realistic. This static environment outside of the inner frustum also helps account for any latency issues between camera movements and real-time rendering.

The importance of frustum lies in its ability to provide visual continuity between shots and scenes. By having a static outer frustum that always surrounds the action, filmmakers can ensure consistency across multiple takes and angles. Without this stable environment, directors must manually adjust lights or props after each shot. Additionally, frustum allows for more seamless transitions between different areas of a scene since all components are connected together within a single frame.

From a technical standpoint, frustum has revolutionized how films are made. Previously, filmmakers had to construct physical sets to achieve what could now be done virtually on computers. Nowadays, teams of digital artists can craft intricate worlds filled with detailed environments without ever leaving their desks. This not only saves time but money as well.