SHADE & SHADOWS
• The shadow of acurved line or irregular shape is the
line that connects the shadows of critical points
along the curve or shape.
rl...f:VATION
• The sh
adow of aplane figure on a para llel plane is
identical insize and shape to the figure.
• The shadow of any polygonal figure on a plane is
circumscribed by the shadows of its shade lines.
• The shadow of acircleisthe intersection of the
cylinder of light rays passing through adjacent
points of the circle and the surface receiving the
shadow. The shape of the shadow is elliptical since
t hesection of acylinder cut by any planeoblique to
its axis is an ellipse. The most convenient method
of determining the shadow of acircle isto
determine the shadow of thesquare or octagon
circumscribing the givencircle, and then to inscribe
within it the elliptical shadow of the circle.
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