Improve debris

src/RandomHelp.hs

@@ -66,9 +66,15 @@ randProb p = do
     return (p1 < p)
 
 randInCirc :: RandomGen g => Float -> State g Point2
-randInCirc maxRad = do 
-    rad <- state $ randomR (0,maxRad)
-    ang <- state $ randomR (0,2*pi)
+randInCirc = randInArc (2*pi)
+
+randInArc :: RandomGen g => Float -> Float -> State g Point2
+randInArc = randInArcStrip 0
+
+randInArcStrip :: RandomGen g => Float -> Float -> Float -> State g Point2
+randInArcStrip minrad maxangle maxRad = do 
+    rad <- state $ randomR (minrad,maxRad)
+    ang <- state $ randomR (0,maxangle)
     return $ rad *.* unitVectorAtAngle ang
 
 randOnUnitSphere :: RandomGen g => State g Point3