OBLIQUE PERSPECTIVE (2 VANISHING POINTS)
It is the perspective of objects in a sharp-corner position before our vision.
The oblique perspective can be constructed only inside a parallel perspective. The reasoning is as follows: the parallel perspective represents our visual field, a space with a limited lateral image of up to 3m to the right plus 3m to the left and an ample vision ahead, reaching the infinity on the horizon line.
This space, this visual field is fixed, without movement.
The oblique perspective represents the movement existing inside this static space.
Objects in oblique perspective are seen from a sharp corner and constructed with two opposed lateral points and their view point is the same both for the parallel and the oblique perspective, because the two perspectives represent the vision of a single viewer.