Perspective Practices, Continued
Curves and
circles in
perspective
Curves and circles in perspective appear in true shape and size when the
surface containing the curve or circle is parallel to the picture plane. Curves
and circles on surfaces not parallel to the picture plane appear as ellipses.
Ellipses have no direct transferable measurement; therefore you must place
the circle within a square. By inscribing the circle within a square, the
vanishing points and proportions of the curves are easily determined.
To lay out a circle in one-point perspective, use this table:
Step
Action
1
Draw a circle with the dimensions desired (figure
view A).
2
Draw a square circumscribing the circle. Construct center lines and
diagonals inside the square. The intersections of the circle, the
center lines, and the diagonals give you eight checkpoints for
drawing the circle in perspective (figure
view B).
3
Draw the square in one-point perspective including the center lines
and diagonals (figure
view C).
4
Draw in the circle through the eight checkpoints (figure
view
D).
Continued on next page
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