X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?a=blobdiff_plain;f=helixish.py;h=bf8083fbd35dcc137f044027461e59bd0610003a;hb=db59c229b019128b1c4d46bcc9ad61f06e7f2be9;hp=b1eac1ce34bab6881bd4f2cfb49205816a7e9466;hpb=62a6501559d7214249c7ba969586432e651d1372;p=moebius3.git

diff --git a/helixish.py b/helixish.py
index b1eac1c..bf8083f 100644
--- a/helixish.py
+++ b/helixish.py
@@ -161,6 +161,7 @@ class HelixishCurve():
         def railway_ST(C, start, end, railway_r):
           delta = atan2(*(end - C)[0:2]) - atan2(*(start - C)[0:2])
           dbg('railway_ST C', C, 'start', start, 'end', end, 'delta', delta)
+          if delta < 0: delta += tau
           s = delta * railway_r
           dbg('railway_ST delta', delta, 'r', railway_r, 's', s)
           return s