Dynamic Rendering using only the Vertices that are in Camera View

Here is a method using the “Dynamic Paint” & “Mask” modifiers to only use the parts of an object that are in the camera view.
For instance, if you are doing a close-up render of a 2 million vertices Dinosaur showing just the face area, Blender will calculate ALL the vertices during the render taking up vast amounts of time and memory (VRAM).
The modifiers trick shown in the video reduces the number of vertices to those shown in the camera view (for any given frame).
This can dramatically reduce the amount of time and VRAM, depending on how dense the model is, and how close you are viewing.