# How to draw parallel inclined surfaces in perspective

I know the steps for how to draw a surface in perspective using two vanishing points. I mean, I know how to draw a box, a pyramid, and a cone.

Now I got into a situation where I need to draw the following:

Can anyone give me an explanation? Or a reference to a book?

I know Ernest Norling's "Perspective Made Easy", but I don't think that he talks about oblique, or inclined, surfaces there.

Note: Let's keep the discussion about how to draw it with just a pencil and a straightedge on a paper (maybe a compass or a protractor, but not with this or that graphics software).

• It'd be much faster to do this in a 3d software Commented Nov 6, 2022 at 13:31
• Ok. seems like this is a XY question. I mean if yo have a oblique surface than its exactly the same as a non oblique surface. Commented Nov 6, 2022 at 14:35
• You probably should learn to project 2 2D images to the scene instead of bothering to try to work with elementary 2 point perspective. This entirely sidesteps any problems you have. Commented Nov 6, 2022 at 14:45

## 1 Answer

If it were me, I'd only use one vanishing point (*see note below), and some parallel lines. Be aware that as the parallel lines get closer to the vanishing point, they should be get closer together (since they will be further away), to give the illusion of depth.

A very rough example

*Note: You could technically have a second vanishing point for the parallel lines, but it would need to be very far away, somewhere way off the page likely. I wouldn't trouble with that TBH. It won't make the drawing look better. Keep it simple. In any case the human brain/eye won't likely be able to spot that the parallel lines converge on some very distant vanishing point.

Can you tell that these lines converge on a vanishing point located way off the page?

• I think OP does not know how to space the planes, or do this in conjunction to other existing parts of the drawing. Commented Nov 6, 2022 at 14:43
• @joojaa Hmm, maybe. I think it's more important that the parallel lines just appear to get closer as they approach the vanishing point to give the illusion of depth. This would be fine for a mere illustration where precise measurements are not that crucial. The human brain/eye should still get message, since we are so easily fooled. If accuracy is needed then 3D software would be probably be easier, but the OP doesn't want to talk about software. But I'm guessing you could probably answer this using maths!!!! Commented Nov 6, 2022 at 15:03
• No there's better approach to drawing perspective than the one usually shown. The way architects would draw perspective hundreds of years back Commented Nov 6, 2022 at 16:30
• @joojaa - sure but this is graphic design, not architecture. My answer has more to do with making a "pretty picture" than a technically perfect drawing. Of course it all depends on what the OP really wants - is it art, or is it technical ;) Commented Nov 6, 2022 at 16:53
• its not that its for "architects" only, its just that once your drawing gets more complicated it saves you time when you don't have to guess so much. They used to teach commercial artists this stuff but for some reason they stopped doing this in 1990-2000's. So definitely something classical artists knew how to do, Commented Nov 6, 2022 at 17:23