## Where to put the vp for a right angle

##### 3:20 PM, Sunday July 18th 2021

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

I try to construct the left box as a right angled box, but I don't know how to construct it / where to put the lines / where the vanishing point should be.

I hope my question is understandable.

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
0 users agree
##### 10:42 AM, Tuesday July 20th 2021

There isn't a single set distance between the two VP's needed in order to get 90 degrees. The distance will depend on the type of lens effect you want to produce.

Here is a video timestamped to the relevant parts about lenses

https://youtu.be/2XF5YuAK63I?t=251

In short, if you want a dramatic, distorted, look then bring the two VP's closer together. This emulates a wide-angle camera lens.

If you want to get closer to an isographic, more regular, look then you spread them further apart. That emulates a long-angle camera lens.

So, with all that said, that doesn't really help you get a good box like you were asking for. I recommend starting off practicing what is called the Y-Method. IIRC Uncomfortable mentions it in the box challenge material. In any case, the Y-method has you draw the closest corner/edges first and.

The discord has this image pinned in their Lesson 1 channel that might help:

https://cdn.discordapp.com/attachments/368870697742630912/384092950700752896/BoxDemo.png

Notice that the image states the angles between the lines should never be less than 90 when using the Y-method. (You'll also see what is called The Arrow Method for when you have a 2-point-perspective box that is placed directly in front of the horizon line. I'd say stick with the Y-method until you get the hang of it.)

I feel this video from Proko does a good job breaking down the intuitions you are wanting to develop as you draw a box using the Y-method:

https://youtu.be/3uEtdDvK6Xo?t=308

It isn't timestamped exactly to the Y-method part but it is worth watching the entire segment, in my opinion, so I timestamped it there.