Two-liner; Torous

[John_L._Graham@adbbs.antioch.edu (John L. Graham)]

Whew! I hate time change. I thought I'd finish this one before stepping
outside to watch Mir fly overhead then go to bed. Anywho, this little
two-liner repeatedly draws, then erases, a torous which passes in/out of
the plane of the screen. The most significant difference between this and
the coil code is a sine term which enlarges the diameter of the torous in
the y direction as it passes out of the plane of the screen, and shrinks
it as it passes into the screen. This gives a since of perspective and
reduces the number of points that plot on top of each other. To further
reduce the problem of points on top of each other and odd-ball number was
used for number of points per circle (33) and circles per revolution (57).
 
 0  REM 'TOROUS' A TWO-LINER BY JOHN L. GRAHAM. CONTROL-C TO STOP.
 1 A = 8 *  ATN (1):B = 33:C = A / B:D = 1:E = 57:F = D * E:G = D * A /
   F:H = 30:I = 10:J = 190 - 2 * H:K = J / F:L = 100:M = 140:N = 0:O = 96:
   HGR2
 2 N = N + 1:P = (N - 2 *  INT (N / 2)) * 3: HCOLOR= P: FOR Q = 0 TO F:
   R = Q * G:S =  COS (R):T = H * S:U = M - L * S:V = H + I *  SIN (R):
   FOR W = 0 TO A STEP C:X = U + T *  COS (W):Y = O + V *  SIN (W): HPLOT
   X,Y: NEXT : NEXT : GOTO 2
 
Have fun!
 
John