1 users agree
##### 4:43 PM, Sunday July 18th 2021 edited at 4:49 PM, Jul 18th 2021

Hi!

That is a one point perspective and there is only one vanishing point for the scene, the one you have already established. Lines that do not go toward the vanishing point are either perpendicular or parallel to the horizon line, as you have already drawn them.

I have completed the box with color coded lines and notes: https://imgur.com/a/j4Jz63v

I would always think in terms of lines that go toward the VP, that are parallel or perpendicular, leaving the right angle thing as a final check to see if the front and back planes are drawn correctly.

EDIT: oh wait a moment, maybe I have misunderstood your question: did you want to extrude the box to the left? If that is the case I'll do another picture.

edited at 4:49 PM, Jul 18th 2021
##### 5:50 PM, Sunday July 18th 2021

I'm not sure what by extrude is meant. And it's kinda hard to explain with words now, so I made a second quick sketch (the one on the right turn out sloppy).

https://i.imgur.com/mcVQT4W.jpg

but basically my question is, how far have the vanishing points be apart so that the cube has right angles. there has to be some construction process and they can't be both right because then how would you construct a box with other angles then 90°?

##### 6:09 PM, Sunday July 18th 2021 edited at 5:56 AM, Jul 19th 2021

This is how you can get a 90 degree angle on a 2 point perspective. The two Vps must be equally distant from the point that originates the angle.

Right now I can't think of other solutions.

EDIT: forgot to mention that also the height of the point from the HL must be the same length.

edited at 5:56 AM, Jul 19th 2021
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