Data commit

Task/Dragon-curve/Chipmunk-Basic/dragon-curve.basic

@@ -0,0 +1,37 @@
+10 rem Dragon curve
+20 rem sin, cos in arrays for pi/4 multipl.
+30 dim s(7),c(7)
+40 for i = 0 to 7
+50   s(i) = sin(i*pi/4) : c(i) = cos(i*pi/4)
+60 next i
+70 level = 15
+80 insize = 256 : rem 2^whole_num (looks better)
+90 x = 224 : y = 140
+100 sq = sqr(2)
+110 rotqpi = 0 : rq = 1
+120 dim r(level)
+130 graphics 0 : graphics cls
+140 gosub 160
+150 end
+160 rem Dragon
+170 rotqpi = rotqpi and 7
+180 if level <= 1 then
+190   yn = s(rotqpi)*insize+y
+200   xn = c(rotqpi)*insize+x
+210   graphics moveto x,y : graphics lineto xn,yn
+220   x = xn : y = yn
+230 else
+240   insize = insize*sq/2
+250   rotqpi = (rotqpi+rq) and 7
+260   level = level-1
+270   r(level) = rq : rq = 1
+280   gosub 160
+290   rotqpi = (rotqpi-r(level)*2) and 7
+300   rq = -1
+310   gosub 160
+320   rq = r(level)
+330   rotqpi = (rotqpi+rq) and 7
+340   level = level+1
+350   insize = insize*sq
+360 endif
+370 return