improve graph lines

fcore/normal-mode.sml

@@ -160,7 +160,8 @@ struct
 
       val maxSide = Int.max (canvasWidth, canvasHeight)
       val squares =
-        CollisionTree.toTriangles (windowWidth, windowHeight, squares, maxSide)
+        CollisionTree.toTriangles (windowWidth, windowHeight, squares, maxSide,
+        canvasWidth, canvasHeight, xClickPoints, yClickPoints)
       val drawMsg = DRAW_SQUARES_AND_DOTS {squares = squares, dots = dotVec}
     in
       (model, [DRAW drawMsg])
@@ -180,11 +181,13 @@ struct
     let
       val model = AppWith.windowResize (model, width, height)
 
-      val {squares, canvasWidth, canvasHeight, showGraph, arrowX, arrowY, ...} =
+      val {squares, canvasWidth, canvasHeight, showGraph, arrowX, arrowY,
+      xClickPoints, yClickPoints, ...} =
         model
       val maxSide = Int.max (canvasWidth, canvasHeight)
 
-      val squares = CollisionTree.toTriangles (width, height, squares, maxSide)
+      val squares = CollisionTree.toTriangles (width, height, squares, maxSide,
+      canvasWidth, canvasHeight, xClickPoints, yClickPoints)
 
       val graphLines =
         if showGraph then GraphLines.generate model else Vector.fromList []