import three; size(15cm); defaultrender.merge=true; currentprojection=perspective(24,14,13); currentlight=light(gray(0.5),specularfactor=3,viewport=false, (0.5,-0.5,-0.25),(0.5,0.5,0.25),(0.5,0.5,1),(-0.5,-0.5,-1)); defaultpen(0.75mm); path3 g=arc(O,1,90,-60,90,60); transform3 t=shift(invert(3S,O)); draw(g,blue,Arrows3(TeXHead3),currentlight); draw(scale3(3)*g,green,ArcArrows3(HookHead3),currentlight); draw(scale3(6)*g,red,Arrows3(DefaultHead3),currentlight); draw(t*g,blue,Arrows3(TeXHead2),currentlight); draw(t*scale3(3)*g,green,ArcArrows3(HookHead2,NoFill),currentlight); draw(t*scale3(6)*g,red,Arrows3(DefaultHead2(normal=Z)),currentlight);