How to Spot Mistakes of Squares in Perspective

In this video, Vladimir London, a Life Drawing Academy tutor (lifedrawing.academy), will explain how to spot and avoid mistakes when drawing squares in perspective.
Let's draw some squares below the horizon level. They are seen from above in the two-point perspective. There are two vanishing points for each square. To spot mistakes, we can inscribe a perfect ellipse into a square. If such an ellipse does not touch all four sides of the square in the middle of each side, that shape is not a square, but a rectangle. As you can see, green dots touch the shape sides, but red points do not. That is why these two shapes are rectangles. However, the third shape has all four points touching the shape's outlines, but those points are not in the middle of each side, therefore it is not a square, but a distorted quadrilateral shape.
Let's make another drawing, this time, making sure it follows the rules. Because a circle can be inscribed into a square, and such a circle will touch all four sides in the middle of each side, so in perspective that circle will appear as a perfect elliptical oval that touches all sides in the middle. I mark these places as green dots. So, this square is correct.
To learn more about constructive drawing rules, check out the Life Drawing Academy course - lifedrawing.academy/free

[@memoriessomeonewewillnever732]

Thanks a lot for sharing this video I was waiting for it.

[@DrawingArtAcademy]

Most welcome 😊