Attempt to detect sharp-turns.

1 files changed, 8 insertions, 3 deletions

diff --git a/MeshSketch.hs b/MeshSketch.hs
index ea8fbe6..7cda3fc 100644
--- a/MeshSketch.hs
+++ b/MeshSketch.hs
@@ -622,10 +622,15 @@ pushRing w st h k c = do
     g <- pushFront (fromList [h,k]) <$> readIORef (stRecentPts st)
     writeIORef (stRecentPts st) g
     with3 g $ \a b c -> do
-        let d = det $ fromRows [(b-c),(a-b)]
-        putStrLn $ "d = " ++ show d
+        let û = unit $ a-b
+            v̂ = unit $ b-c
+            δ = norm_1 $ (a-b)^2
+            d = det $ fromRows [û,v̂]
+            x = dot û v̂
+        putStrLn $ "(d,x) = " ++ show (d,x)
         updateBack (stRingBuffer st) $ \RingPoint{..} -> do
-            rpColor @<- if d<0 then blue else red
+            rpColor @<- if x < 0.3 || δ<0.5 then yellow
+                                            else if d<0 then blue else red
     pushBack (stRingBuffer st) $ \RingPoint{..} -> do
         rpPosition @<- d
         rpColor @<- c