CONSTRUCTION OF A SHADOW OF A CIRCLE, PERPENDICULAR HORIZONTAL PLANE OF PROJECTIONS

The contour of the shadow of a circle perpendicular to the horizontal plane of the projections on this plane is an ellipse. The large diagonal of the ellipse is the shadow of a vertical line.

Building a circle shadow on the plot.

In the parallelogram, which is the shadow of the square described around the circumference, an ellipse fits into eight points.