fix follow_path for objects with start_pos

CHANGELOG.md

@@ -10,6 +10,7 @@
 - tutorial on partial draw / show creation 
 - Few tests for morphs added
 - test for partial draw/ show creation
+- fix for `follow_path` for objects with `start_pos` other than O
 
 ## v0.9.0 (26th of May 2022)
 - Ability to use Luxor functionality without rendering an animation

src/action_animations.jl

@@ -416,26 +416,26 @@ function _follow_path(video, object, action, rel_frame, points; closed = closed)
     # if t is discrete and not 0.0 take the last point or first if closed
     if !isfirstframe && isapprox_discrete(t)
         if closed
-            translate(points[1])
+            translate(points[1] - object.start_pos)
         else
-            translate(points[end])
+            translate(points[end] - object.start_pos)
         end
         return
     end
     # get only the frobjectal part to be between 0 and 1
     t -= floor(t)
     if isfirstframe
         # compute the distances only once for performance reasons
-        action.defs[:p_dist] = polydistances(points, closed = closed)
+        action.defs[:p_dist] = polydistances(points .- object.start_pos, closed = closed)
     end
     if isapprox(t, 0.0, atol = 1e-4)
-        translate(points[1])
+        translate(points[1] - object.start_pos)
         return
     end
     pdist = action.defs[:p_dist]
 
     overshootpoint = get_polypoint_at(points, t; pdist = pdist)
-    translate(overshootpoint)
+    translate(overshootpoint - object.start_pos)
 end
 
 """