function bezier_move(x1,y1,x2,y2,x3,y3,x4,y4,t1,t2,accel,afterimage_blur,afterimage_dur,density) if density == 0 or density == nil then density = 1 end if afterimage_blur == 0 or afterimage_blur == nil then x_blur = 0 y_blur = 0 else x_blur = math.random(-afterimage_blur,afterimage_blur) y_blur = math.random(-afterimage_blur,afterimage_blur) end if afterimage_dur == nil or afterimage_dur < frame_dur then afterimage_dur = frame_dur end  if accel == nil then accel = 1 end x_pos = {} y_pos = {} dur = t2 - t1 frames = math.floor(dur/(frame_dur/density)) x_pos[j] =  (1-(j/frames)^accel)^3 * x1 + 3*(1-(j/frames)^accel)^2 * ((j/frames)^accel) * x2 + 3*(1-(j/frames)^accel) * ((j/frames)^accel)^2 * x3 + ((j/frames)^accel)^3 * x4  y_pos[j] = (1-(j/frames)^accel)^3 * y1 + 3*(1-(j/frames)^accel)^2 * ((j/frames)^accel) * y2 + 3*(1-(j/frames)^accel) * ((j/frames)^accel)^2 * y3 + ((j/frames)^accel)^3 * y4  if j == 1 then maxloop(frames) end retime("presyl",t1+(j-1)*(frame_dur/density),t1+j*(frame_dur/density)+afterimage_dur) return string.format("\\move(%f,%f,%f,%f)",x_pos[j],y_pos[j],x_pos[j] + x_blur ,y_pos[j] + y_blur) end