Quote Originally Posted by Xei View Post
There's something I don't understand about vanishing point art (with respects to using one, two, three, four, etc. vanishing points): which one is correct (in the sense that it matches human perception, or a photograph)? Or are they equivalent?
I'm not sure if PhilStoned answered your question, coz I don't understand what he wrote.
But basically, they are all correct.
You just use them for different angles.
One point is for drawing objects from pretty much any direction/angle that has a side of the object facing you.

Two point is when you want to have a horizon line and you have to have one of the corners of the object facing you. For example, looking at the corner of a building.

Three point is when you want to have the object appear to be "distorted" from every angle.
For example, looking at a building from the horizon line, showing the side's distortion and also the top's distortion. (By distortion I just mean getting smaller).

Basically, you add a point for every plane which needs to appear as if it's going in to the distance.

Four point would be if you wanted to be looking at the middle of the building, from a corner, so it's getting smaller on all planes.