Camera3D: Difference between PROJECTION_PERSPECTIVE and PROJECTION_FRUSTUM

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:bust_in_silhouette: Asked By throwaway89767

As the title suggests, what is the main difference between the 2 projection modes? After trying them out with a sample 3D scene, they look nearly identical. Online results also seem to use the 2 terms interchangeably.

:bust_in_silhouette: Reply From: klaas

Hi,
frustum projection is mostly the same as perspective projection but you have the ability to alter the frustum offset manualy.
Create a camera and look frome the side to see the frustum gizmo.
Then change the frustum offset y. You see the camera projection gets sheared.

This effect was used in old 2.5D shooter like Duke Nukem

What to do with this? I dont know! Maybe someone can shed some light on this!