Function frustum 

pub fn frustum(
    left: f32,
    right: f32,
    bottom: f32,
    top: f32,
    near: f32,
    far: f32,
) -> Mat4

Creates a perspective projection matrix from a frustum for use with OpenGL.

Expects a left-handed Y-up view space input. Outputs NDC with Z in [-1, 1] and Y-up.

Panics

Will panic if near or far are less than or equal to zero when glam_assert is enabled.