In this video, you will learn how to draw a perfect horizontal square in perspective. To learn drawing, take the Life Drawing Academy course - lifedrawing.academy/free
We begin with the vertical symmetry axis and a perfect ellipse. At the top, there is the horizon. The axis crosses it on the vanishing point. Two tilted vanishing lines converge into that point. Together with two horizontal lines, they form a square in one-point perspective. Two diagonals of that square cross the ellipse in four points, marked here in red. A smaller square can be built using these four points. This square is also seen in one-point perspective. Another ellipse can be inscribed into that square. Now, ;et's take any random point on the bigger ellipse. I mark it as "A". A straight line goes from that point, touching the inner ellipse at the point "B". On the opposite side, it reaches the outer ellipse at the point "C". This ellipse is actually an oval because its center is seen in perspective. Through this center, we can draw a line that crosses the oval at the opposite side in the point "D". Points "C" and "D" can be connected with a straight line. It touches the inner oval in the middle. Another line from the point "C" goes through the oval's center and reaches the opposite side in the point "E". Points "A", "E" and "D" can be connected together. This gives us a perfect square in two-point perspective. We know this square is perfect because a perfectly horizontal ellipse is inscribed inside of it.
Let's make another drawing of a square in perspective, this time modifying the sequence of drawing steps. We begin with an ellipse. Two vanishing lines are touching this ellipse at two sides. Two more vanishing lines complete the square in two-point perspective. The oval's center is found as the cross-point of two diagonals of that square. If two vanishing lines cross the oval in the middle of each side of the square, such a square is depicted correctly. All that is left is to outline the perfect square in two-point perspective. Note that the side of a square that is closer to a viewer is bolder than the sides that are further away. Vanishing lines of that square will converge into two vanishing points, which are located on the same horizon line somewhere beyond the drawing area.
We can now make one more drawing of squares in perspective. Let's mark the horizon line. The one-point perspective vanishing point is located on that horizon. One square in one-point perspective is seen from above because it is depicted below the horizon. We inscribe an ellipse into that square and mark two diagonals, which cross at the center of the oval. A smaller square and its oval fit inside. Following the method described above, we can build a perfect square in the two-point perspective. It is outlined in brown and that outline has varying boldness according to the aerial perspective. Using this geometry as the guide, we can draw two more squares of the same size in the same perspective, but at different elevations. The second square is also below the horizon and therefore is seen from above. However, it is higher than the first square and that is why it will be more foreshortened. The vertical lines of the corner points are already in place, so we could outline the square straight away. The same goes for the top square, which is above the horizon and seen from below. Note which outlines are bolder and which are slimmer. As you can see, the vanishing lines are converging into the first vanishing point on the left. This point is on the horizon. The second vanishing point is also on the horizon, but beyond the drawing area.
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