Final version

graphics/cylon.py

@@ -0,0 +1,33 @@
+#!/usr/bin/env python3
+from math import sin, pi
+from collections import Counter
+
+W = 128         # screen width
+PW = 12         # width of eye
+parts = 53      # of animation steps
+
+dr = (2*pi) / parts
+RW = W - PW - 1
+
+ampl = (RW/2) + .5
+offset = (W/2) - (PW/2)
+
+rv = []
+r = 0
+for n in range(parts):
+    x = (ampl * sin(r)) + offset
+    x = int(x+.5)
+    print(f'{n:2d}: {x:3d}   ' + (' '*x) + 'X')
+    r += dr
+    rv.append(x)
+
+assert rv[0]+(PW//2) == W//2, rv[0]
+assert max(rv) == W-PW, max(rv)
+assert min(rv) == 0, min(rv)
+
+# only want it to hesitate at the ends
+cnt = Counter(rv).most_common()
+assert max(c for x,c in cnt) == 2, repr(cnt)
+
+print("\nResult: " + ', '.join(str(i) for i in rv))
+print("\ncylon = %r" % bytes(rv))