diff --git a/dotscape b/dotscape
deleted file mode 100755
index b506713..0000000
Binary files a/dotscape and /dev/null differ
diff --git a/dotscape.mlb b/dotscape.mlb
index 315585a..01dbd2b 100644
--- a/dotscape.mlb
+++ b/dotscape.mlb
@@ -1,35 +1,36 @@
 $(SML_LIB)/basis/basis.mlb
 
 (* FUNCTIONAL CORE *)
-functional-core/app/app-type.sml
+fcore/app-type.sml
 
 ann
   "allowVectorExps true"
 in
-  functional-core/app/ndc.sml
-  functional-core/app/click-points.sml
-  functional-core/app/graph-lines.sml
-  functional-core/app/triangles.sml
+  fcore/ndc.sml
+  fcore/graph-lines.sml
   cozette-sml/fonts/cozette-ascii.mlb
 end
 
-functional-core/app/triangle-stage.sml
+fcore/click-points.sml
+fcore/app-init.sml
+fcore/app-with.sml
 
-functional-core/app/app-init.sml
-functional-core/app/app-with.sml
-
-message-types/input-msg.sml
-message-types/file-msg.sml
 message-types/draw-msg.sml
+message-types/file-msg.sml
+message-types/input-msg.sml
 message-types/update-msg.sml
 
-functional-core/app/app-update.sml
+fcore/quad-tree.sml
+
+fcore/common-update.sml
+fcore/normal-mode.sml
+fcore/browse-mode.sml
+fcore/app-update.sml
 
 (* pure file parsing functions *)
-functional-core/file/parse-file.sml
+fcore/parse-file.sml
 
 (* IMPERATIVE SHELL *)
-$(SML_LIB)/basis/mlton.mlb
 $(SML_LIB)/cml/cml.mlb
 
 ann
diff --git a/temp-squares/fcore/app-init.sml b/fcore/app-init.sml
similarity index 100%
rename from temp-squares/fcore/app-init.sml
rename to fcore/app-init.sml
diff --git a/temp-squares/fcore/app-type.sml b/fcore/app-type.sml
similarity index 100%
rename from temp-squares/fcore/app-type.sml
rename to fcore/app-type.sml
diff --git a/temp-squares/fcore/app-update.sml b/fcore/app-update.sml
similarity index 100%
rename from temp-squares/fcore/app-update.sml
rename to fcore/app-update.sml
diff --git a/temp-squares/fcore/app-with.sml b/fcore/app-with.sml
similarity index 100%
rename from temp-squares/fcore/app-with.sml
rename to fcore/app-with.sml
diff --git a/temp-squares/fcore/browse-mode.sml b/fcore/browse-mode.sml
similarity index 98%
rename from temp-squares/fcore/browse-mode.sml
rename to fcore/browse-mode.sml
index f7cd19e..60470f3 100644
--- a/temp-squares/fcore/browse-mode.sml
+++ b/fcore/browse-mode.sml
@@ -14,16 +14,11 @@ struct
     else
       let
         val chr = String.sub (str, pos)
-        val chrVec = Vector.fromList []
-
-        (*
-        *
 
         val chrFun = Vector.sub (CozetteAscii.asciiTable, Char.ord chr)
         val chrVec = chrFun
           (startX, startY, 25.0, 25.0, windowWidth, windowHeight, r, g, b)
 
-        * *)
         val acc = chrVec :: acc
       in
         stringToVec
diff --git a/temp-squares/fcore/click-points.sml b/fcore/click-points.sml
similarity index 100%
rename from temp-squares/fcore/click-points.sml
rename to fcore/click-points.sml
diff --git a/temp-squares/fcore/common-update.sml b/fcore/common-update.sml
similarity index 100%
rename from temp-squares/fcore/common-update.sml
rename to fcore/common-update.sml
diff --git a/temp-squares/fcore/graph-lines.sml b/fcore/graph-lines.sml
similarity index 100%
rename from temp-squares/fcore/graph-lines.sml
rename to fcore/graph-lines.sml
diff --git a/temp-squares/fcore/ndc.sml b/fcore/ndc.sml
similarity index 100%
rename from temp-squares/fcore/ndc.sml
rename to fcore/ndc.sml
diff --git a/temp-squares/fcore/normal-mode.sml b/fcore/normal-mode.sml
similarity index 100%
rename from temp-squares/fcore/normal-mode.sml
rename to fcore/normal-mode.sml
diff --git a/fcore/parse-file.sml b/fcore/parse-file.sml
new file mode 100644
index 0000000..da5fe38
--- /dev/null
+++ b/fcore/parse-file.sml
@@ -0,0 +1,5 @@
+structure ParseFile =
+struct
+  (* unimplemented *)
+  fun parseLine line = NONE
+end
diff --git a/temp-squares/fcore/quad-tree.sml b/fcore/quad-tree.sml
similarity index 100%
rename from temp-squares/fcore/quad-tree.sml
rename to fcore/quad-tree.sml
diff --git a/ffi/export.h b/ffi/export.h
index 5864c66..c1080ad 100644
--- a/ffi/export.h
+++ b/ffi/export.h
@@ -157,10 +157,6 @@ typedef Pointer Objptr;
 extern "C" {
 #endif
 
-MLLIB_PUBLIC(void mltonMouseMoveCallback (Real32 x0, Real32 x1);)
-MLLIB_PUBLIC(void mltonMouseClickCallback (Int32 x0, Int32 x1);)
-MLLIB_PUBLIC(void mltonFramebufferSizeCallback (Int32 x0, Int32 x1);)
-MLLIB_PUBLIC(void mltonKeyCallback (Int32 x0, Int32 x1, Int32 x2, Int32 x3);)
 
 #undef MLLIB_PRIVATE
 #undef MLLIB_PUBLIC
diff --git a/functional-core/app/app-init.sml b/functional-core/app/app-init.sml
deleted file mode 100644
index e027ca0..0000000
--- a/functional-core/app/app-init.sml
+++ /dev/null
@@ -1,88 +0,0 @@
-signature APP_INIT =
-sig
-  val fromWindowWidthAndHeight: int * int * int * int -> AppType.app_type
-end
-
-structure AppInit :> APP_INIT =
-struct
-  open AppType
-
-  fun helpFromWidthAndHeight
-    ( windowWidth
-    , windowHeight
-    , wStart
-    , wFinish
-    , hStart
-    , hFinish
-    , widthClickPoints
-    , heightClickPoints
-    ) : app_type =
-    let
-      val xClickPoints =
-        ClickPoints.generate (wStart, wFinish, widthClickPoints)
-      val yClickPoints =
-        ClickPoints.generate (hStart, hFinish, heightClickPoints)
-    in
-      { mode = AppType.NORMAL_MODE
-      , triangles = []
-      , triangleStage = NO_TRIANGLE
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , numClickPointsX = widthClickPoints
-      , numClickPointsY = heightClickPoints
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , undo = []
-      , redo = []
-      , mouseX = 0.0
-      , mouseY = 0.0
-      , showGraph = true
-      , arrowX = 0
-      , arrowY = 0
-      , openFilePath = ""
-      , fileBrowser = Vector.fromList []
-      , fileBrowserIdx = 0
-      , r = 0.0
-      , g = 0.0
-      , b = 0.0
-      , num = 0
-      }
-    end
-
-  fun fromWindowWidthAndHeight
-    (windowWidth, windowHeight, widthClickPoints, heightClickPoints) =
-    if windowWidth > windowHeight then
-      let
-        val difference = windowWidth - windowHeight
-        val wStart = difference div 2
-        val wFinish = wStart + windowHeight
-      in
-        helpFromWidthAndHeight
-          ( windowWidth
-          , windowHeight
-          , wStart
-          , wFinish
-          , 0
-          , windowHeight
-          , widthClickPoints
-          , heightClickPoints
-          )
-      end
-    else
-      let
-        val difference = windowHeight - windowWidth
-        val hStart = difference div 2
-        val hFinish = hStart + windowWidth
-      in
-        helpFromWidthAndHeight
-          ( windowWidth
-          , windowHeight
-          , 0
-          , windowWidth
-          , hStart
-          , hFinish
-          , widthClickPoints
-          , heightClickPoints
-          )
-      end
-end
diff --git a/functional-core/app/app-type.sml b/functional-core/app/app-type.sml
deleted file mode 100644
index 15b0ffb..0000000
--- a/functional-core/app/app-type.sml
+++ /dev/null
@@ -1,58 +0,0 @@
-structure AppType =
-struct
-  datatype app_mode = NORMAL_MODE | BROWSE_MODE
-
-  datatype file_browser_item = IS_FILE of string | IS_FOLDER of string
-
-  type triangle =
-    { x1: Real32.real
-    , x2: Real32.real
-    , x3: Real32.real
-    , y1: Real32.real
-    , y2: Real32.real
-    , y3: Real32.real
-    , r: Real32.real
-    , g: Real32.real
-    , b: Real32.real
-    }
-
-  datatype triangle_stage =
-    NO_TRIANGLE
-  (* 
-   * triangle_stage represents a work-in-progress triangle which is not fully completed,
-   * because user has to click one (x, y) pair, then a second pair, 
-   * and then a third, to draw a complete triangle.
-   *
-   * There is no THIRD triangle_stage because that represents a complete triangle, 
-   * which should be added to the `triangles` list. 
-   *)
-  | FIRST of {x1: Real32.real, y1: Real32.real}
-  | SECOND of
-      {x1: Real32.real, y1: Real32.real, x2: Real32.real, y2: Real32.real}
-
-  type app_type =
-    { mode: app_mode
-    , triangles: triangle list
-    , triangleStage: triangle_stage
-    , windowWidth: int
-    , windowHeight: int
-    , numClickPointsX: int
-    , numClickPointsY: int
-    , xClickPoints: Real32.real vector
-    , yClickPoints: Real32.real vector
-    , undo: (Real32.real * Real32.real) list
-    , redo: (Real32.real * Real32.real) list
-    , showGraph: bool
-    , mouseX: Real32.real
-    , mouseY: Real32.real
-    , arrowX: int
-    , arrowY: int
-    , openFilePath: string
-    , fileBrowser: file_browser_item vector
-    , fileBrowserIdx: int
-    , r: Real32.real
-    , g: Real32.real
-    , b: Real32.real
-    , num: int
-    }
-end
diff --git a/functional-core/app/app-update.sml b/functional-core/app/app-update.sml
deleted file mode 100644
index 06f6f1f..0000000
--- a/functional-core/app/app-update.sml
+++ /dev/null
@@ -1,607 +0,0 @@
-signature APP_UPDATE =
-sig
-  val update: AppType.app_type * InputMessage.t
-              -> AppType.app_type * UpdateMessage.t list
-end
-
-structure AppUpdate :> APP_UPDATE =
-struct
-  open AppType
-
-  open DrawMessage
-  open FileMessage
-  open InputMessage
-  open UpdateMessage
-
-  fun getDotVecFromIndices (model, hIdx, vIdx) =
-    let
-      val {windowWidth, windowHeight, ...} = model
-      val xpos = Vector.sub (#xClickPoints model, hIdx)
-      val ypos = Vector.sub (#yClickPoints model, vIdx)
-    in
-      ClickPoints.getDrawDotRgb
-        (xpos, ypos, 1.0, 0.0, 0.0, windowWidth, windowHeight)
-    end
-
-  fun mouseMoveOrRelease (model: app_type) =
-    let
-      val drawVec =
-        case ClickPoints.getClickPositionFromMouse model of
-          SOME (hIdx, vIdx) => getDotVecFromIndices (model, hIdx, vIdx)
-        | NONE => Vector.fromList []
-      val drawVec = TriangleStage.toVector (model, drawVec)
-
-      val drawMsg = DRAW_DOT drawVec
-      val drawMsg = [DRAW drawMsg]
-    in
-      (model, drawMsg)
-    end
-
-  fun getDrawDotMsgWhenArrowIsAtBoundary model =
-    let
-      val {arrowX, arrowY, ...} = model
-      val dotVec = getDotVecFromIndices (model, arrowX, arrowY)
-      val dotVec = TriangleStage.toVector (model, dotVec)
-      val drawMsg = DRAW_DOT dotVec
-      val drawMsg = [DRAW drawMsg]
-    in
-      (model, drawMsg)
-    end
-
-  fun moveArrowUp (model: app_type) =
-    let
-      val {arrowX, arrowY, ...} = model
-    in
-      if arrowY > 0 then
-        let
-          val newArrowY = arrowY - 1
-          val model = AppWith.arrowY (model, newArrowY)
-
-          val dotVec = getDotVecFromIndices (model, arrowX, newArrowY)
-          val dotVec = TriangleStage.toVector (model, dotVec)
-          val drawMsg = DRAW_DOT dotVec
-          val drawMsg = [DRAW drawMsg]
-        in
-          (model, drawMsg)
-        end
-      else
-        getDrawDotMsgWhenArrowIsAtBoundary model
-    end
-
-  fun moveArrowLeft (model: app_type) =
-    let
-      val {arrowX, arrowY, ...} = model
-    in
-      if arrowX > 0 then
-        let
-          val newArrowX = arrowX - 1
-          val model = AppWith.arrowX (model, newArrowX)
-
-          val dotVec = getDotVecFromIndices (model, newArrowX, arrowY)
-          val dotVec = TriangleStage.toVector (model, dotVec)
-          val drawMsg = DRAW_DOT dotVec
-          val drawMsg = [DRAW drawMsg]
-        in
-          (model, drawMsg)
-        end
-      else
-        getDrawDotMsgWhenArrowIsAtBoundary model
-    end
-
-  fun moveArrowRight (model: app_type) =
-    let
-      val {arrowX, arrowY, xClickPoints, ...} = model
-    in
-      if arrowX < Vector.length xClickPoints - 1 then
-        let
-          val newArrowX = arrowX + 1
-          val model = AppWith.arrowX (model, newArrowX)
-
-          val dotVec = getDotVecFromIndices (model, newArrowX, arrowY)
-          val dotVec = TriangleStage.toVector (model, dotVec)
-          val drawMsg = DRAW_DOT dotVec
-          val drawMsg = [DRAW drawMsg]
-        in
-          (model, drawMsg)
-        end
-      else
-        getDrawDotMsgWhenArrowIsAtBoundary model
-    end
-
-  fun moveArrowDown (model: app_type) =
-    let
-      val {arrowX, arrowY, yClickPoints, ...} = model
-    in
-      if arrowY < Vector.length yClickPoints - 1 then
-        let
-          val newArrowY = arrowY + 1
-          val model = AppWith.arrowY (model, newArrowY)
-
-          val dotVec = getDotVecFromIndices (model, arrowX, newArrowY)
-          val dotVec = TriangleStage.toVector (model, dotVec)
-          val drawMsg = DRAW_DOT dotVec
-          val drawMsg = [DRAW drawMsg]
-        in
-          (model, drawMsg)
-        end
-      else
-        getDrawDotMsgWhenArrowIsAtBoundary model
-    end
-
-  fun addCoordinates (model: app_type, hIdx, vIdx) =
-    let
-      val
-        { windowWidth
-        , windowHeight
-        , xClickPoints
-        , yClickPoints
-        , triangleStage
-        , ...
-        } = model
-
-      val xpos = Vector.sub (xClickPoints, hIdx)
-      val ypos = Vector.sub (yClickPoints, vIdx)
-      val dotVec = ClickPoints.getDrawDotRgb
-        (xpos, ypos, 0.0, 0.0, 1.0, windowWidth, windowHeight)
-
-      val halfWidth = Real32.fromInt (windowWidth div 2)
-      val halfHeight = Real32.fromInt (windowHeight div 2)
-      val hpos =
-        ClickPoints.xposToNdc (xpos, windowWidth, windowHeight, halfWidth)
-      val vpos =
-        ClickPoints.yposToNdc (ypos, windowWidth, windowHeight, halfHeight)
-
-      val newUndoTuple = (hpos, vpos)
-    in
-      case triangleStage of
-        NO_TRIANGLE =>
-          let
-            val drawVec = TriangleStage.toVector (model, dotVec)
-            val drawMsg = DRAW_DOT drawVec
-            val drawMsg = [DRAW drawMsg]
-
-            val newTriangleStage = FIRST {x1 = hpos, y1 = vpos}
-            val model = AppWith.addTriangleStage
-              (model, newTriangleStage, newUndoTuple, hIdx, vIdx)
-          in
-            (model, drawMsg)
-          end
-      | FIRST {x1, y1} =>
-          let
-            val drawVec = TriangleStage.firstToVector (x1, y1, dotVec, model)
-            val drawMsg = DRAW_DOT drawVec
-            val drawMsg = [DRAW drawMsg]
-
-            val newTriangleStage = SECOND
-              {x1 = x1, y1 = y1, x2 = hpos, y2 = vpos}
-            val model = AppWith.addTriangleStage
-              (model, newTriangleStage, newUndoTuple, hIdx, vIdx)
-          in
-            (model, drawMsg)
-          end
-      | SECOND {x1, y1, x2, y2} =>
-          let
-            val model = AppWith.addTriangle
-              (model, x1, y1, x2, y2, hpos, vpos, newUndoTuple, hIdx, vIdx)
-            val drawVec = Triangles.toVector model
-            val drawMsg = DRAW_TRIANGLES_AND_RESET_DOTS drawVec
-            val drawMsg = [DRAW drawMsg]
-          in
-            (model, drawMsg)
-          end
-    end
-
-  fun mouseLeftClick model =
-    case ClickPoints.getClickPositionFromMouse model of
-      SOME (hIdx, vIdx) => addCoordinates (model, hIdx, vIdx)
-    | NONE => (model, [])
-
-  fun enterOrSpaceCoordinates model =
-    let val {arrowX, arrowY, ...} = model
-    in addCoordinates (model, arrowX, arrowY)
-    end
-
-  fun resizeWindow (model, width, height) =
-    let
-      val model = AppWith.windowResize (model, width, height)
-      val triangles = Triangles.toVector model
-
-      val graphLines =
-        if #showGraph model then GraphLines.generate model
-        else Vector.fromList []
-
-      val dots = TriangleStage.toVector (model, Vector.fromList [])
-
-      val drawMsg =
-        RESIZE_TRIANGLES_DOTS_AND_GRAPH
-          {triangles = triangles, graphLines = graphLines, dots = dots}
-      val drawMsg = [DRAW drawMsg]
-    in
-      (model, drawMsg)
-    end
-
-  fun undoAction model =
-    case #triangleStage model of
-      FIRST {x1, y1} =>
-        (* Change FIRST to NO_TRIANGLE and clear dots. *)
-        let
-          val model =
-            AppWith.undo (model, NO_TRIANGLE, #triangles model, (x1, y1))
-        in
-          (model, [DRAW CLEAR_DOTS])
-        end
-    | SECOND {x1, y1, x2, y2} =>
-        (* Change FIRST to SECOND and redraw dots. *)
-        let
-          val newTriangleStage = FIRST {x1 = x1, y1 = y1}
-          val model =
-            AppWith.undo (model, newTriangleStage, #triangles model, (x2, y2))
-
-          val emptyVec: Real32.real vector = Vector.fromList []
-          val drawVec = TriangleStage.firstToVector (x1, y1, emptyVec, model)
-          val drawMsg = DRAW_DOT drawVec
-          val drawMsg = [DRAW drawMsg]
-        in
-          (model, drawMsg)
-        end
-    | NO_TRIANGLE =>
-        (case #triangles model of
-           {x1, y1, x2, y2, x3, y3, r, g, b} :: trianglesTl =>
-             (* Have to slice off (x3, y3) from triangle head,
-              * turn (x1, y1, x2, y2) into a triangleStage,
-              * and redraw both triangle and triangleStage. *)
-             let
-               val triangleStage = SECOND {x1 = x1, y1 = y1, x2 = x2, y2 = y2}
-               val model =
-                 AppWith.undo (model, triangleStage, trianglesTl, (x3, y3))
-
-               val newTriangleVec = Triangles.toVector model
-               val emptyVec: Real32.real vector = Vector.fromList []
-               val drawVec = TriangleStage.secondToVector
-                 (x1, y1, x2, y2, emptyVec, model)
-               val drawMsg =
-                 DRAW_TRIANGLES_AND_DOTS
-                   {triangles = newTriangleVec, dots = drawVec}
-               val drawMsg = [DRAW drawMsg]
-             in
-               (model, drawMsg)
-             end
-         | [] =>
-             (* Can't undo, because there are no actions to undo. *)
-             (model, []))
-
-  fun redoAction model =
-    case #redo model of
-      (redoHd as (x, y)) :: tl =>
-        (* There is a click point to redo. *)
-        (case #triangleStage model of
-           NO_TRIANGLE =>
-             (* add to triangle stage, and redraw dots *)
-             let
-               val newTriangleStage = FIRST {x1 = x, y1 = y}
-               val model =
-                 AppWith.redo
-                   (model, newTriangleStage, #triangles model, redoHd)
-
-               val emptyVec: Real32.real vector = Vector.fromList []
-               val drawVec = TriangleStage.firstToVector (x, y, emptyVec, model)
-               val drawMsg = DRAW_DOT drawVec
-               val drawMsg = [DRAW drawMsg]
-             in
-               (model, drawMsg)
-             end
-         | FIRST {x1, y1} =>
-             (* add to triangle stage, redraw dots *)
-             let
-               val newTriangleStage = SECOND {x1 = x1, y1 = y1, x2 = x, y2 = y}
-               val model =
-                 AppWith.redo
-                   (model, newTriangleStage, #triangles model, redoHd)
-
-               val emptyVec: Real32.real vector = Vector.fromList []
-               val drawVec = TriangleStage.secondToVector
-                 (x1, y1, x, y, emptyVec, model)
-               val drawMsg = DRAW_DOT drawVec
-               val drawMsg = [DRAW drawMsg]
-             in
-               (model, drawMsg)
-             end
-         | SECOND {x1, y1, x2, y2} =>
-             (* clear triangle stage, add to trinagle list and redraw triangles *)
-             let
-               val {r, g, b, ...} = model
-               val newTriangleStage = NO_TRIANGLE
-               val newTriangle =
-                 { x1 = x1
-                 , y1 = y1
-                 , x2 = x2
-                 , y2 = y2
-                 , x3 = x
-                 , y3 = y
-                 , r = r
-                 , g = g
-                 , b = b
-                 }
-               val newTriangles = newTriangle :: (#triangles model)
-               val model =
-                 AppWith.redo (model, newTriangleStage, newTriangles, redoHd)
-
-               val drawVec = Triangles.toVector model
-               val drawMsg = DRAW_TRIANGLES_AND_RESET_DOTS drawVec
-               val drawMsg = [DRAW drawMsg]
-             in
-               (model, drawMsg)
-             end)
-    | [] => (* Nothing to redo. *) (model, [])
-
-  fun toggleGraph (model: app_type) =
-    if #showGraph model then
-      let
-        val model = AppWith.graphVisibility (model, false)
-        val drawMsg = DRAW_GRAPH (Vector.fromList [])
-        val drawMsg = [DRAW drawMsg]
-      in
-        (model, drawMsg)
-      end
-    else
-      let
-        val model = AppWith.graphVisibility (model, true)
-        val graphLines = GraphLines.generate model
-        val drawMsg = DRAW_GRAPH graphLines
-        val drawMsg = [DRAW drawMsg]
-      in
-        (model, drawMsg)
-      end
-
-  fun updateNum (model: app_type, inputNum) =
-    let
-      val oldNum = #num model
-      val newNum = oldNum * 10 + inputNum
-      val newNum = if newNum > 255 then 0 else newNum
-    in
-      (AppWith.num (model, newNum), [])
-    end
-
-  fun updateRed model = (AppWith.r model, [])
-  fun updateGreen model = (AppWith.g model, [])
-  fun updateBlue model = (AppWith.b model, [])
-
-  fun getSaveTrianglesMsg model =
-    let
-      val {triangles, ...} = model
-      val fileMsg = SAVE_TRIANGLES triangles
-      val fileMsg = [FILE fileMsg]
-    in
-      (model, fileMsg)
-    end
-
-  fun getLoadTrianglesMsg model =
-    (model, [FILE LOAD_TRIANGLES])
-
-  fun getExportTrianglesMsg model =
-    let
-      val {triangles, ...} = model
-      val fileMsg = EXPORT_TRIANGLES (#triangles model)
-      val fileMsg = [FILE fileMsg]
-    in
-      (model, fileMsg)
-    end
-
-  fun useTrianglesInNormalMode (model, triangles) =
-    let
-      val model = AppWith.useTrianglesAndSetNormalMode (model, triangles)
-      val drawVec = Triangles.toVector model
-      val drawMsg = DRAW_TRIANGLES_AND_RESET_DOTS drawVec
-      val drawMsg = [DRAW drawMsg]
-    in
-      (model, drawMsg)
-    end
-
-  fun trianglesLoadError model = (model, [])
-
-  fun enterBrowseMode model =
-    let
-      val model = AppWith.mode (model, AppType.BROWSE_MODE)
-      (* todo: should draw modal window as well *)
-      val fileMsg = LOAD_FILES (#openFilePath model)
-      val fileMsg = [FILE fileMsg]
-    in
-      (model, fileMsg)
-    end
-
-  fun handleFileBrowserAndPathInNormalMode (model, fileBrowser, path) =
-    let val model = AppWith.fileBrowserAndPath (model, fileBrowser, path)
-    in (model, [])
-    end
-
-  fun updateNormalMode (model: app_type, inputMsg) =
-    case inputMsg of
-      MOUSE_MOVE {x = mouseX, y = mouseY} =>
-        let val model = AppWith.mousePosition (model, mouseX, mouseY)
-        in mouseMoveOrRelease model
-        end
-    | MOUSE_LEFT_RELEASE => mouseMoveOrRelease model
-    | MOUSE_LEFT_CLICK => mouseLeftClick model
-    | NUM num => updateNum (model, num)
-    | KEY_R => updateRed model
-    | KEY_G => updateGreen model
-    | KEY_B => updateBlue model
-    | RESIZE_WINDOW {width, height} => resizeWindow (model, width, height)
-    | UNDO_ACTION => undoAction model
-    | REDO_ACTION => redoAction model
-    | KEY_T => toggleGraph model
-    | KEY_CTRL_S => getSaveTrianglesMsg model
-    | KEY_CTRL_L => getLoadTrianglesMsg model
-    | KEY_CTRL_E => getExportTrianglesMsg model
-    | KEY_CTRL_O => enterBrowseMode model
-    | ARROW_UP => moveArrowUp model
-    | ARROW_LEFT => moveArrowLeft model
-    | ARROW_RIGHT => moveArrowRight model
-    | ARROW_DOWN => moveArrowDown model
-    | KEY_ENTER => enterOrSpaceCoordinates model
-    | KEY_SPACE => enterOrSpaceCoordinates model
-    | USE_TRIANGLES triangles => useTrianglesInNormalMode (model, triangles)
-    | TRIANGLES_LOAD_ERROR => trianglesLoadError model
-    | FILE_BROWSER_AND_PATH {fileBrowser, path} =>
-        handleFileBrowserAndPathInNormalMode (model, fileBrowser, path)
-
-  fun stringToVec
-    (pos, str, acc, startX, startY, windowWidth, windowHeight, r, g, b) =
-    if pos = String.size str then
-      acc
-    else
-      let
-        val chr = String.sub (str, pos)
-        val chrFun = Vector.sub (CozetteAscii.asciiTable, Char.ord chr)
-        val chrVec = chrFun
-          (startX, startY, 25.0, 25.0, windowWidth, windowHeight, r, g, b)
-        val acc = chrVec :: acc
-      in
-        stringToVec
-          ( pos + 1
-          , str
-          , acc
-          , startX + 12
-          , startY
-          , windowWidth
-          , windowHeight
-          , r
-          , g
-          , b
-          )
-      end
-
-  fun buildFileBrowserText
-    (pos, fileBrowser, acc, startY, windowWidth, windowHeight, selectedIdx) =
-    if pos = Vector.length fileBrowser then
-      Vector.concat acc
-    else
-      let
-        val item = Vector.sub (fileBrowser, pos)
-        val itemText =
-          case item of
-            IS_FILE str => str
-          | IS_FOLDER str => str
-        val acc =
-          if pos <> selectedIdx then
-            stringToVec
-              ( 0
-              , itemText
-              , acc
-              , 10
-              , startY
-              , windowWidth
-              , windowHeight
-              , 0.0
-              , 0.0
-              , 0.0
-              )
-          else
-            stringToVec
-              ( 0
-              , itemText
-              , acc
-              , 10
-              , startY
-              , windowWidth
-              , windowHeight
-              , 0.35
-              , 0.35
-              , 0.75
-              )
-      in
-        buildFileBrowserText
-          ( pos + 1
-          , fileBrowser
-          , acc
-          , startY + 23
-          , windowWidth
-          , windowHeight
-          , selectedIdx
-          )
-      end
-
-  fun redrawFileBrowser (model: app_type) =
-    let
-      val {windowWidth, windowHeight, fileBrowser, fileBrowserIdx, ...} = model
-      val ww = Real32.fromInt windowWidth
-      val wh = Real32.fromInt windowHeight
-      val textVec = buildFileBrowserText
-        (0, fileBrowser, [], 10, ww, wh, fileBrowserIdx)
-
-      val drawMsg = DRAW_MODAL_TEXT textVec
-    in
-      (model, [DRAW drawMsg])
-    end
-
-  fun handleFileBrowserAndPathInBrowseMode (model, fileBrowser, path) =
-    let val model = AppWith.fileBrowserAndPath (model, fileBrowser, path)
-    in redrawFileBrowser model
-    end
-
-  fun browseModeArrowUp (model: app_type) =
-    let
-      val {fileBrowser, fileBrowserIdx, ...} = model
-
-      val fileBrowserIdx =
-        if fileBrowserIdx > 0 then fileBrowserIdx - 1
-        else Int.max (0, Vector.length fileBrowser - 1)
-
-      val model = AppWith.fileBrowserIdx (model, fileBrowserIdx)
-    in
-      redrawFileBrowser model
-    end
-
-  fun browseModeArrowDown (model: app_type) =
-    let
-      val {fileBrowser, fileBrowserIdx, ...} = model
-
-      val fileBrowserIdx =
-        if fileBrowserIdx = Vector.length fileBrowser - 1 then 0
-        else fileBrowserIdx + 1
-
-      val model = AppWith.fileBrowserIdx (model, fileBrowserIdx)
-    in
-      redrawFileBrowser model
-    end
-
-  fun selectCurrentFileItem model =
-    let
-      val {fileBrowser, fileBrowserIdx, openFilePath, ...} = model
-    in
-      if Vector.length fileBrowser > 0 then
-        let
-          val path =
-            case Vector.sub (fileBrowser, fileBrowserIdx) of
-              IS_FILE str => str
-            | IS_FOLDER str => str
-          val path = String.concat [openFilePath, "/", path]
-          val fileMsg = SELECT_PATH path
-        in
-          (model, [FILE fileMsg])
-        end
-      else
-        (model, [])
-    end
-
-  fun updateBrowseMode (model: app_type, inputMsg) =
-    case inputMsg of
-      ARROW_UP => browseModeArrowUp model
-    | ARROW_DOWN => browseModeArrowDown model
-    | TRIANGLES_LOAD_ERROR => trianglesLoadError model
-    (* todo: 
-    | ARROW_LEFT =>
-    *)
-    | ARROW_RIGHT => selectCurrentFileItem model
-    | KEY_ENTER => selectCurrentFileItem model
-    | KEY_SPACE => selectCurrentFileItem model
-    | FILE_BROWSER_AND_PATH {fileBrowser, path} =>
-        handleFileBrowserAndPathInBrowseMode (model, fileBrowser, path)
-    | USE_TRIANGLES triangles => useTrianglesInNormalMode (model, triangles)
-    | _ => (model, [])
-
-  fun update (model: app_type, inputMsg) =
-    case #mode model of
-      NORMAL_MODE => updateNormalMode (model, inputMsg)
-    | BROWSE_MODE => updateBrowseMode (model, inputMsg)
-end
diff --git a/functional-core/app/app-with.sml b/functional-core/app/app-with.sml
deleted file mode 100644
index 2d23cc2..0000000
--- a/functional-core/app/app-with.sml
+++ /dev/null
@@ -1,995 +0,0 @@
-structure AppWith =
-struct
-  open AppType
-
-  (* add to undo, clear redo *)
-  fun addTriangleStage
-    (app: app_type, newTriangleStage: triangle_stage, newUndoHd, arrowX, arrowY) :
-    app_type =
-    let
-      val
-        { triangleStage = _
-        , mode
-        , triangles
-        , numClickPointsX
-        , numClickPointsY
-        , xClickPoints
-        , yClickPoints
-        , windowWidth
-        , windowHeight
-        , undo
-        , redo = _
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX = _
-        , arrowY = _
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b
-        , num
-        } = app
-
-      val newUndo = newUndoHd :: undo
-    in
-      { triangleStage = newTriangleStage
-      , undo = newUndo
-      , redo = []
-      , mode = mode
-      , triangles = triangles
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  fun addTriangle
-    (app: app_type, x1, y1, x2, y2, x3, y3, newUndoHd, arrowX, arrowY) :
-    app_type =
-    let
-      val
-        { mode
-        , triangles
-        , triangleStage = _
-        , numClickPointsX
-        , numClickPointsY
-        , xClickPoints
-        , yClickPoints
-        , windowWidth
-        , windowHeight
-        , undo
-        , redo = _
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX = _
-        , arrowY = _
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b
-        , num
-        } = app
-
-      val newTriangle =
-        { x1 = x1
-        , y1 = y1
-        , x2 = x2
-        , y2 = y2
-        , x3 = x3
-        , y3 = y3
-        , r = r
-        , g = g
-        , b = b
-        }
-      val newTriangles = newTriangle :: triangles
-      val newUndo = newUndoHd :: undo
-    in
-      { mode = mode
-      , triangleStage = NO_TRIANGLE
-      , triangles = newTriangles
-      , undo = newUndo
-      , redo = []
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  fun arrowX (app: app_type, arrowX) =
-    let
-      val
-        { mode
-        , xClickPoints
-        , yClickPoints
-        , numClickPointsX
-        , numClickPointsY
-        , windowWidth
-        , windowHeight
-        , triangles
-        , triangleStage
-        , undo
-        , redo
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX = _
-        , arrowY
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b
-        , num
-        } = app
-    in
-      { mode = mode
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , triangles = triangles
-      , triangleStage = triangleStage
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , undo = undo
-      , redo = redo
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  fun arrowY (app: app_type, arrowY) =
-    let
-      val
-        { mode
-        , xClickPoints
-        , yClickPoints
-        , numClickPointsX
-        , numClickPointsY
-        , windowWidth
-        , windowHeight
-        , triangles
-        , triangleStage
-        , undo
-        , redo
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY = _
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b
-        , num
-        } = app
-    in
-      { mode = mode
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , triangles = triangles
-      , triangleStage = triangleStage
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , undo = undo
-      , redo = redo
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  fun helpWindowResize
-    (app: app_type, windowWidth, windowHeight, wStart, wFinish, hStart, hFinish) :
-    app_type =
-    let
-      val
-        { mode
-        , xClickPoints = _
-        , yClickPoints = _
-        , numClickPointsX
-        , numClickPointsY
-        , windowWidth = _
-        , windowHeight = _
-        , triangles
-        , triangleStage
-        , undo
-        , redo
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b
-        , num
-        } = app
-
-      val xClickPoints = ClickPoints.generate (wStart, wFinish, numClickPointsX)
-      val yClickPoints = ClickPoints.generate (hStart, hFinish, numClickPointsY)
-    in
-      { mode = mode
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , triangles = triangles
-      , triangleStage = triangleStage
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , undo = undo
-      , redo = redo
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  fun windowResize (app: app_type, windowWidth, windowHeight) =
-    if windowWidth = windowHeight then
-      helpWindowResize
-        (app, windowWidth, windowHeight, 0, windowWidth, 0, windowHeight)
-    else if windowWidth > windowHeight then
-      let
-        val difference = windowWidth - windowHeight
-        val wStart = difference div 2
-        val wFinish = wStart + windowHeight
-      in
-        helpWindowResize
-          (app, windowWidth, windowHeight, wStart, wFinish, 0, windowHeight)
-      end
-    else
-      let
-        val difference = windowHeight - windowWidth
-        val hStart = difference div 2
-        val hFinish = hStart + windowWidth
-      in
-        helpWindowResize
-          (app, windowWidth, windowHeight, 0, windowWidth, hStart, hFinish)
-      end
-
-  fun mousePosition (app: app_type, mouseX, mouseY) =
-    let
-      val
-        { mode
-        , mouseX = _
-        , mouseY = _
-        , triangles
-        , triangleStage
-        , numClickPointsX
-        , numClickPointsY
-        , xClickPoints
-        , yClickPoints
-        , windowWidth
-        , windowHeight
-        , undo
-        , redo
-        , showGraph
-        , arrowX
-        , arrowY
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b
-        , num
-        } = app
-    in
-      { mode = mode
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , triangles = triangles
-      , triangleStage = triangleStage
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , undo = undo
-      , redo = redo
-      , showGraph = showGraph
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  (* add to redo, pop one from undo *)
-  fun undo (app: app_type, newTriangleStage, newTriangles, newRedoHd) =
-    let
-      val
-        { mode
-        , triangleStage = _
-        , triangles = _
-        , numClickPointsX
-        , numClickPointsY
-        , xClickPoints
-        , yClickPoints
-        , windowWidth
-        , windowHeight
-        , undo
-        , redo
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b
-        , num
-        } = app
-
-      val newUndo =
-        case undo of
-          hd :: tl => tl
-        | empty => empty
-
-      val newRedo = newRedoHd :: redo
-    in
-      { mode = mode
-      , triangleStage = newTriangleStage
-      , triangles = newTriangles
-      , undo = newUndo
-      , redo = newRedo
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  (* add to undo, pop one from redo *)
-  fun redo (app: app_type, newTriangleStage, newTriangles, newUndoHd) =
-    let
-      val
-        { mode
-        , triangleStage = _
-        , triangles = _
-        , numClickPointsX
-        , numClickPointsY
-        , xClickPoints
-        , yClickPoints
-        , windowWidth
-        , windowHeight
-        , undo
-        , redo
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b
-        , num
-        } = app
-
-      val newUndo = newUndoHd :: undo
-      val newRedo =
-        case redo of
-          hd :: tl => tl
-        | empty => empty
-    in
-      { mode = mode
-      , triangleStage = newTriangleStage
-      , triangles = newTriangles
-      , undo = newUndo
-      , redo = newRedo
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  fun graphVisibility (app: app_type, shouldShowGraph) =
-    let
-      val
-        { mode
-        , triangleStage
-        , triangles
-        , numClickPointsX
-        , numClickPointsY
-        , xClickPoints
-        , yClickPoints
-        , windowWidth
-        , windowHeight
-        , undo
-        , redo
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY
-        , showGraph = _
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b
-        , num
-        } = app
-    in
-      { mode = mode
-      , showGraph = shouldShowGraph
-      , triangleStage = triangleStage
-      , triangles = triangles
-      , undo = undo
-      , redo = redo
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  fun mode (app: app_type, newMode) =
-    let
-      val
-        { mode = _
-        , triangleStage
-        , triangles
-        , numClickPointsX
-        , numClickPointsY
-        , xClickPoints
-        , yClickPoints
-        , windowWidth
-        , windowHeight
-        , undo
-        , redo
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY
-        , showGraph
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b
-        , num
-        } = app
-    in
-      { mode = newMode
-      , showGraph = showGraph
-      , triangleStage = triangleStage
-      , triangles = triangles
-      , undo = undo
-      , redo = redo
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  fun useTrianglesAndSetNormalMode (app: app_type, triangles) =
-    let
-      val
-        { mode = _
-        , xClickPoints
-        , yClickPoints
-        , numClickPointsX
-        , numClickPointsY
-        , windowWidth
-        , windowHeight
-        , undo
-        , redo
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY
-        , triangles = _
-        , triangleStage = _
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b
-        , num
-        } = app
-
-      val triangleStage = NO_TRIANGLE
-    in
-      { mode = AppType.NORMAL_MODE
-      , triangleStage = triangleStage
-      , triangles = triangles
-      , undo = []
-      , redo = []
-      , showGraph = showGraph
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  fun fileBrowserAndPath (app: app_type, fileBrowser, path) =
-    let
-      val
-        { mode
-        , xClickPoints
-        , yClickPoints
-        , numClickPointsX
-        , numClickPointsY
-        , windowWidth
-        , windowHeight
-        , triangles
-        , triangleStage
-        , undo
-        , redo
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY
-        , openFilePath = _
-        , fileBrowser = _
-        , fileBrowserIdx = _
-        , r
-        , g
-        , b
-        , num
-        } = app
-    in
-      { mode = mode
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , triangles = triangles
-      , triangleStage = triangleStage
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , undo = undo
-      , redo = redo
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = path
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = 0
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  fun fileBrowserIdx (app: app_type, newFileBrowserIdx) =
-    let
-      val
-        { mode
-        , xClickPoints
-        , yClickPoints
-        , numClickPointsX
-        , numClickPointsY
-        , windowWidth
-        , windowHeight
-        , triangles
-        , triangleStage
-        , undo
-        , redo
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY
-        , openFilePath = openFilePath
-        , fileBrowser = fileBrowser
-        , fileBrowserIdx = _
-        , r
-        , g
-        , b
-        , num
-        } = app
-    in
-      { mode = mode
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , triangles = triangles
-      , triangleStage = triangleStage
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , undo = undo
-      , redo = redo
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = newFileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = num
-      }
-    end
-
-  fun num (app: app_type, newNum) : app_type =
-    let
-      val
-        { triangleStage
-        , mode
-        , triangles
-        , numClickPointsX
-        , numClickPointsY
-        , xClickPoints
-        , yClickPoints
-        , windowWidth
-        , windowHeight
-        , undo
-        , redo
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b
-        , num = _
-        } = app
-
-    in
-      { triangleStage = triangleStage
-      , undo = undo
-      , redo = []
-      , mode = mode
-      , triangles = triangles
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = b
-      , num = newNum
-      }
-    end
-
-  fun r (app: app_type) : app_type =
-    let
-      val
-        { triangleStage
-        , mode
-        , triangles
-        , numClickPointsX
-        , numClickPointsY
-        , xClickPoints
-        , yClickPoints
-        , windowWidth
-        , windowHeight
-        , undo
-        , redo
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r = _
-        , g
-        , b
-        , num
-        } = app
-
-      val newR = Real32.fromInt num / 255.0
-    in
-      { triangleStage = triangleStage
-      , undo = undo
-      , redo = []
-      , mode = mode
-      , triangles = triangles
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = newR
-      , g = g
-      , b = b
-      , num = 0
-      }
-    end
-
-  fun g (app: app_type) : app_type =
-    let
-      val
-        { triangleStage
-        , mode
-        , triangles
-        , numClickPointsX
-        , numClickPointsY
-        , xClickPoints
-        , yClickPoints
-        , windowWidth
-        , windowHeight
-        , undo
-        , redo
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g = _
-        , b
-        , num
-        } = app
-
-      val newG = Real32.fromInt num / 255.0
-    in
-      { triangleStage = triangleStage
-      , undo = undo
-      , redo = []
-      , mode = mode
-      , triangles = triangles
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = newG
-      , b = b
-      , num = 0
-      }
-    end
-
-  fun b (app: app_type) : app_type =
-    let
-      val
-        { triangleStage
-        , mode
-        , triangles
-        , numClickPointsX
-        , numClickPointsY
-        , xClickPoints
-        , yClickPoints
-        , windowWidth
-        , windowHeight
-        , undo
-        , redo
-        , showGraph
-        , mouseX
-        , mouseY
-        , arrowX
-        , arrowY
-        , openFilePath
-        , fileBrowser
-        , fileBrowserIdx
-        , r
-        , g
-        , b = _
-        , num
-        } = app
-
-      val newB = Real32.fromInt num / 255.0
-    in
-      { triangleStage = triangleStage
-      , undo = undo
-      , redo = []
-      , mode = mode
-      , triangles = triangles
-      , numClickPointsX = numClickPointsX
-      , numClickPointsY = numClickPointsY
-      , xClickPoints = xClickPoints
-      , yClickPoints = yClickPoints
-      , windowWidth = windowWidth
-      , windowHeight = windowHeight
-      , showGraph = showGraph
-      , mouseX = mouseX
-      , mouseY = mouseY
-      , arrowX = arrowX
-      , arrowY = arrowY
-      , openFilePath = openFilePath
-      , fileBrowser = fileBrowser
-      , fileBrowserIdx = fileBrowserIdx
-      , r = r
-      , g = g
-      , b = newB
-      , num = 0
-      }
-    end
-end
diff --git a/functional-core/app/click-points.sml b/functional-core/app/click-points.sml
deleted file mode 100644
index 9f53944..0000000
--- a/functional-core/app/click-points.sml
+++ /dev/null
@@ -1,127 +0,0 @@
-signature CLICK_POINTS =
-sig
-  val generate: int * int * int -> Real32.real vector
-  val getClickPositionFromMouse: AppType.app_type -> (int * int) option
-
-  val getDrawDot: Real32.real * Real32.real * int * int -> Real32.real vector
-
-  val getDrawDotRgb:
-    Real32.real
-    * Real32.real
-    * Real32.real
-    * Real32.real
-    * Real32.real
-    * int
-    * int
-    -> Real32.real vector
-
-  (* two below functions convert pixel coordinates to normalised device coordinates *)
-  val xposToNdc: Real32.real * int * int * Real32.real -> Real32.real
-  val yposToNdc: Real32.real * int * int * Real32.real -> Real32.real
-end
-
-structure ClickPoints :> CLICK_POINTS =
-struct
-  fun generate (start, finish, numPoints) =
-    let
-      val difference = finish - start
-      val increment = Real32.fromInt difference / Real32.fromInt numPoints
-      val start = Real32.fromInt start
-    in
-      Vector.tabulate (numPoints + 1, fn idx =>
-        (Real32.fromInt idx * increment) + start)
-    end
-
-  (*
-   * Range to detect from clickable position. 
-   * For example, if we have a clickable position at (x, y) = (500, 500),
-   * with a range of 15, we can detect clicks targeting this position 
-   * from top left at (485, 485) to bottom right at (515, 515).
-   * *)
-  val range = 15.0
-
-  fun getClickPos (clickPoints, mousePos, idx) =
-    if idx = Vector.length clickPoints then
-      NONE
-    else
-      let
-        val curPos = Vector.sub (clickPoints, idx)
-      in
-        if mousePos < curPos - range orelse mousePos > curPos + range then
-          getClickPos (clickPoints, mousePos, idx + 1)
-        else
-          SOME idx
-      end
-
-  fun getClickPositionFromMouse (app: AppType.app_type) =
-    case getClickPos (#xClickPoints app, #mouseX app, 0) of
-      SOME hIdx =>
-        (case getClickPos (#yClickPoints app, #mouseY app, 0) of
-           SOME vIdx => SOME (hIdx, vIdx)
-         | NONE => NONE)
-    | NONE => NONE
-
-  fun getDrawDot (xpos, ypos, windowWidth, windowHeight) =
-    let
-      (* calculate normalised device coordinates *)
-      val halfWidth = Real32.fromInt (windowWidth div 2)
-      val halfHeight = Real32.fromInt (windowHeight div 2)
-      val hpos = xpos - halfWidth
-      val vpos = ~(ypos - halfHeight)
-
-      (* coordinates to form small box around clicked area *)
-      val left = (hpos - 5.0) / halfWidth
-      val right = (hpos + 5.0) / halfWidth
-      val bottom = (vpos - 5.0) / halfHeight
-      val top = (vpos + 5.0) / halfHeight
-    in
-      Ndc.ltrbToVertex (left, top, right, bottom)
-    end
-
-  fun getDrawDotRgb (xpos, ypos, r, g, b, windowWidth, windowHeight) =
-    let
-      (* calculate normalised device coordinates *)
-      val halfWidth = Real32.fromInt (windowWidth div 2)
-      val halfHeight = Real32.fromInt (windowHeight div 2)
-      val hpos = xpos - halfWidth
-      val vpos = ~(ypos - halfHeight)
-
-      (* coordinates to form small box around clicked area *)
-      val left = (hpos - 5.0) / halfWidth
-      val right = (hpos + 5.0) / halfWidth
-      val bottom = (vpos - 5.0) / halfHeight
-      val top = (vpos + 5.0) / halfHeight
-    in
-      Ndc.ltrbToVertexRgb (left, top, right, bottom, r, g, b)
-    end
-
-  fun xposToNdc (xpos, windowWidth, windowHeight, halfWidth) =
-    let
-      val xpos = xpos - halfWidth
-    in
-      if windowWidth > windowHeight then
-        let
-          val difference = windowWidth - windowHeight
-          val offset = Real32.fromInt (difference div 2)
-        in
-          xpos / (halfWidth - offset)
-        end
-      else
-        xpos / halfWidth
-    end
-
-  fun yposToNdc (ypos, windowWidth, windowHeight, halfHeight) =
-    let
-      val ypos = ~(ypos - halfHeight)
-    in
-      if windowHeight > windowWidth then
-        let
-          val difference = windowHeight - windowWidth
-          val offset = Real32.fromInt (difference div 2)
-        in
-          ypos / (halfHeight - offset)
-        end
-      else
-        ypos / halfHeight
-    end
-end
diff --git a/functional-core/app/graph-lines.sml b/functional-core/app/graph-lines.sml
deleted file mode 100644
index e1e5148..0000000
--- a/functional-core/app/graph-lines.sml
+++ /dev/null
@@ -1,214 +0,0 @@
-signature GRAPH_LINES =
-sig
-  val generate: AppType.app_type -> Real32.real vector
-end
-
-structure GraphLines :> GRAPH_LINES =
-struct
-
-  (* this function generates graph lines which look like:
-   * . . .
-   * . . .
-   * . . .
-   * where the dots signify click points.
-   *
-   * I think this is not as useful for plotting points as the other method,
-   * where that other method is similar to graph paper,
-   * but there might be a run-time option to change to the grid genereated by this function
-   * in the future. *)
-  fun generateUnconnectedGrid (app: AppType.app_type) =
-    let
-      val {windowWidth, windowHeight, xClickPoints, yClickPoints, ...} = app
-    in
-      Vector.concat (List.tabulate (Vector.length xClickPoints, fn xIdx =>
-        let
-          val xpos = Vector.sub (xClickPoints, xIdx)
-        in
-          Vector.concat (List.tabulate (Vector.length yClickPoints, fn yIdx =>
-            ClickPoints.getDrawDot
-              (xpos, Vector.sub (yClickPoints, yIdx), windowWidth, windowHeight)))
-        end))
-    end
-
-      (* 
-   * This function only produces the desired result 
-   * when the window is a square and has the aspect ratio 1:1.
-   * This is because the function assumes it can use 
-   * the same position coordinates both horizontally and vertically.
-   *)
-  fun helpGenGraphLinesSquare (pos: Real32.real, limit, acc) =
-    if pos >= limit then
-      Vector.concat acc
-    else
-      let
-        val pos2 = pos + 0.05
-        val vec = 
-          #[ (* x = _.1 *) 
-             pos - 0.002, ~1.0
-           , pos + 0.002, ~1.0
-           , pos + 0.002, 1.0
-
-           , pos + 0.002, 1.0
-           , pos - 0.002, 1.0
-           , pos - 0.002, ~1.0
-
-             (* y = _.1 *)
-           , ~1.0, pos - 0.002
-           , ~1.0, pos + 0.002
-           , 1.0, pos + 0.002
-
-           , 1.0, pos + 0.002
-           , 1.0, pos - 0.002
-           , ~1.0, pos - 0.002 
-
-              (* x = _.05 *)
-           , pos2 - 0.001, ~1.0
-           , pos2 + 0.001, ~1.0
-           , pos2 + 0.001, 1.0
-
-           , pos2 + 0.001, 1.0
-           , pos2 - 0.001, 1.0
-           , pos2 - 0.001, ~1.0
-
-             (* y = _.05 *)
-           , ~1.0, pos2 - 0.001
-           , ~1.0, pos2 + 0.001
-           , 1.0, pos2 + 0.001
-
-           , 1.0, pos2 + 0.001
-           , 1.0, pos2 - 0.001
-           , ~1.0, pos2 - 0.001
-           ]
-        val acc = vec :: acc
-        val nextPos = pos + 0.1
-      in
-        helpGenGraphLinesSquare (nextPos, limit, acc)
-      end
-
-  fun helpGenGraphLinesHorizontal
-    (pos, xClickPoints, acc, halfWidth, yMin, yMax) =
-    if pos = Vector.length xClickPoints then
-      acc
-    else
-      let
-        val curX = Vector.sub (xClickPoints, pos)
-        val ndc = (curX - halfWidth) / halfWidth
-        val vec =
-          if (pos + 1) mod 2 = 0 then 
-            (* if even (thin lines) *) 
-           #[
-              ndc - 0.001, yMin
-            , ndc + 0.001, yMin
-            , ndc + 0.001, yMax
-
-            , ndc + 0.001, yMax
-            , ndc - 0.001, yMax
-            , ndc - 0.001, yMin
-            ]
-          else 
-            (* if odd (thick lines) *) 
-            #[
-               ndc - 0.002, yMin
-             , ndc + 0.002, yMin
-             , ndc + 0.002, yMax
-
-             , ndc + 0.002, yMax
-             , ndc - 0.002, yMax
-             , ndc - 0.002, yMin
-             ]
-        val acc = vec :: acc
-      in
-        helpGenGraphLinesHorizontal
-          (pos + 1, xClickPoints, acc, halfWidth, yMin, yMax)
-      end
-
-  fun helpGenGraphLinesVertical (pos, yClickPoints, acc, halfHeight, xMin, xMax) =
-    if pos = Vector.length yClickPoints then
-      acc
-    else
-      let
-        val curY = Vector.sub (yClickPoints, pos)
-        val ndc = (curY - halfHeight) / halfHeight
-        val vec =
-          if (pos + 1) mod 2 = 0 then 
-            (* if even (thin lines) *) 
-            #[
-               xMin, ndc - 0.001
-             , xMin, ndc + 0.001
-             , xMax, ndc + 0.001
-
-             , xMax, ndc + 0.001
-             , xMax, ndc - 0.001
-             , xMin, ndc - 0.001 
-             ]
-          else 
-            (* if odd (thick lines) *) 
-            #[
-               xMin, ndc - 0.002
-             , xMin, ndc + 0.002
-             , xMax, ndc + 0.002
-
-             , xMax, ndc + 0.002
-             , xMax, ndc - 0.002
-             , xMin, ndc - 0.002 
-             ]
-        val acc = vec :: acc
-      in
-        helpGenGraphLinesVertical
-          (pos + 1, yClickPoints, acc, halfHeight, xMin, xMax)
-      end
-
-  fun helpGenerate (windowWidth, windowHeight, xClickPoints, yClickPoints) =
-    if windowWidth = windowHeight then
-      helpGenGraphLinesSquare (~1.0, 1.0, [])
-    else if windowWidth > windowHeight then
-      let
-        val difference = windowWidth - windowHeight
-        val offset = difference div 2
-
-        val halfWidth = Real32.fromInt (windowWidth div 2)
-        val halfHeight = Real32.fromInt (windowHeight div 2)
-
-        val start = offset - (windowWidth div 2)
-        val start = Real32.fromInt start / halfWidth
-
-        val finish = (windowWidth - offset) - (windowWidth div 2)
-        val finish = Real32.fromInt finish / halfWidth
-
-        val lines = helpGenGraphLinesHorizontal
-          (0, xClickPoints, [], halfWidth, ~1.0, 1.0)
-        val lines = helpGenGraphLinesVertical
-          (0, yClickPoints, lines, halfHeight, start, finish)
-      in
-        Vector.concat lines
-      end
-    else
-      (* windowWidth < windowHeight *)
-      let
-        val difference = windowHeight - windowWidth
-        val offset = difference div 2
-
-        val halfWidth = Real32.fromInt (windowWidth div 2)
-        val halfHeight = Real32.fromInt (windowHeight div 2)
-
-        val start = offset - (windowHeight div 2)
-        val start = Real32.fromInt start / halfHeight
-
-        val finish = (windowHeight - offset) - (windowHeight div 2)
-        val finish = Real32.fromInt finish / halfHeight
-
-        val lines = helpGenGraphLinesHorizontal
-          (0, xClickPoints, [], halfWidth, start, finish)
-        val lines = helpGenGraphLinesVertical
-          (0, yClickPoints, lines, halfHeight, ~1.0, 1.0)
-      in
-        Vector.concat lines
-      end
-
-  fun generate (app: AppType.app_type) = 
-    let
-      val {windowWidth, windowHeight, xClickPoints, yClickPoints, ...} = app
-    in
-      helpGenerate (windowWidth, windowHeight, xClickPoints, yClickPoints)
-    end
-end
diff --git a/functional-core/app/ndc.sml b/functional-core/app/ndc.sml
deleted file mode 100644
index fad4838..0000000
--- a/functional-core/app/ndc.sml
+++ /dev/null
@@ -1,50 +0,0 @@
-structure Ndc = 
-struct
-  (* ndc = normalised device coordinates *)
-  fun ltrbToVertex (left, top, right, bottom) =
-    #[ left, bottom
-     , right, bottom
-     , left, top
-
-     , left, top
-     , right, bottom
-     , right, top
-     ]
-
-  fun ltrbToVertexRgb (left, top, right, bottom, r, g, b) =
-    #[ left, bottom, r, g, b
-     , right, bottom, r, g, b
-     , left, top, r, g, b
-
-     , left, top, r, g, b
-     , right, bottom, r, g, b
-     , right, top, r, g, b
-     ]
-
-  (* This function adjusts the x position to be centre-aligned to the grid
-   * if windowWidth is greater than height 
-   * (where screen size does not have 1:1 aspect ratio). *)
-  fun centreAlignX (x, windowWidth, windowHeight, halfWidth) =
-    if windowWidth > windowHeight then
-      let
-        val difference = windowWidth - windowHeight
-        val offset = Real32.fromInt (difference div 2)
-      in
-        x * (halfWidth - offset)
-      end
-    else
-      x * halfWidth
-
-  (* Similar to centreAlignX, except it centre-aligns the y-point
-   * when windowHeight is greater than windowWidth. *)
-  fun centreAlignY (y, windowWidth, windowHeight, halfHeight) =
-    if windowHeight > windowWidth then
-      let
-        val difference = windowHeight - windowWidth
-        val offset = Real32.fromInt (difference div 2)
-      in
-        y * (halfHeight - offset)
-      end
-    else
-      y * halfHeight
-end
diff --git a/functional-core/app/triangle-stage.sml b/functional-core/app/triangle-stage.sml
deleted file mode 100644
index 9b422be..0000000
--- a/functional-core/app/triangle-stage.sml
+++ /dev/null
@@ -1,64 +0,0 @@
-structure TriangleStage =
-struct
-  open AppType
-
-  fun firstToVector (x1, y1, drawVec, model) =
-    let
-      val windowWidth = #windowWidth model
-      val windowHeight = #windowHeight model
-
-      val halfWidth = Real32.fromInt (windowWidth div 2)
-      val halfHeight = Real32.fromInt (windowHeight div 2)
-
-      val x1px = Ndc.centreAlignX (x1, windowWidth, windowHeight, halfWidth)
-      val left = (x1px - 5.0) / halfWidth
-      val right = (x1px + 5.0) / halfWidth
-
-      val y1px = Ndc.centreAlignY (y1, windowWidth, windowHeight, halfHeight)
-      val top = (y1px + 5.0) / halfHeight
-      val bottom = (y1px - 5.0) / halfHeight
-
-      val firstVec = Ndc.ltrbToVertexRgb
-        (left, top, right, bottom, 0.0, 0.0, 1.0)
-    in
-      Vector.concat [firstVec, drawVec]
-    end
-
-  fun secondToVector (x1, y1, x2, y2, drawVec, model) =
-    let
-      val windowWidth = #windowWidth model
-      val windowHeight = #windowHeight model
-
-      val halfWidth = Real32.fromInt (windowWidth div 2)
-      val halfHeight = Real32.fromInt (windowHeight div 2)
-
-      val x1px = Ndc.centreAlignX (x1, windowWidth, windowHeight, halfWidth)
-      val left = (x1px - 5.0) / halfWidth
-      val right = (x1px + 5.0) / halfWidth
-
-      val y1px = Ndc.centreAlignY (y1, windowWidth, windowHeight, halfHeight)
-      val top = (y1px + 5.0) / halfHeight
-      val bottom = (y1px - 5.0) / halfHeight
-
-      val firstVec = Ndc.ltrbToVertexRgb
-        (left, top, right, bottom, 0.0, 0.0, 1.0)
-
-      val x2px = Ndc.centreAlignX (x2, windowWidth, windowHeight, halfWidth)
-      val left = (x2px - 5.0) / halfWidth
-      val right = (x2px + 5.0) / halfWidth
-
-      val y2px = Ndc.centreAlignY (y2, windowWidth, windowHeight, halfHeight)
-      val top = (y2px + 5.0) / halfHeight
-      val bottom = (y2px - 5.0) / halfHeight
-
-      val secVec = Ndc.ltrbToVertexRgb (left, top, right, bottom, 0.0, 0.0, 1.0)
-    in
-      Vector.concat [firstVec, secVec, drawVec]
-    end
-
-  fun toVector (model: app_type, drawVec) =
-    case #triangleStage model of
-      NO_TRIANGLE => drawVec
-    | FIRST {x1, y1} => firstToVector (x1, y1, drawVec, model)
-    | SECOND {x1, y1, x2, y2} => secondToVector (x1, y1, x2, y2, drawVec, model)
-end
diff --git a/functional-core/app/triangles.sml b/functional-core/app/triangles.sml
deleted file mode 100644
index bcb162f..0000000
--- a/functional-core/app/triangles.sml
+++ /dev/null
@@ -1,57 +0,0 @@
-signature TRIANGLES =
-sig
-  val toVector: AppType.app_type -> Real32.real vector
-end
-
-structure Triangles :> TRIANGLES =
-struct
-  open AppType
-
-  fun helpToVector (lst, acc, windowWidth, windowHeight, halfWidth, halfHeight) =
-    case lst of
-      {x1, y1, x2, y2, x3, y3, r, g, b} :: tl =>
-        let
-          val x1 = Ndc.centreAlignX (x1, windowWidth, windowHeight, halfWidth)
-          val x2 = Ndc.centreAlignX (x2, windowWidth, windowHeight, halfWidth)
-          val x3 = Ndc.centreAlignX (x3, windowWidth, windowHeight, halfWidth)
-
-          val y1 = Ndc.centreAlignY (y1, windowWidth, windowHeight, halfHeight)
-          val y2 = Ndc.centreAlignY (y2, windowWidth, windowHeight, halfHeight)
-          val y3 = Ndc.centreAlignY (y3, windowWidth, windowHeight, halfHeight)
-
-          val vec =
-           #[ x1 / halfWidth
-            , y1 / halfHeight
-            , r
-            , g
-            , b
-            , x2 / halfWidth
-            , y2 / halfHeight
-            , r
-            , g
-            , b
-            , x3 / halfWidth
-            , y3 / halfHeight
-            , r
-            , g
-            , b
-            ]
-          val acc = vec :: acc
-        in
-          helpToVector
-            (tl, acc, windowWidth, windowHeight, halfWidth, halfHeight)
-        end
-    | [] => acc
-
-  fun toVector (app: app_type) =
-    let
-      val windowWidth = #windowWidth app
-      val windowHeight = #windowHeight app
-      val halfWidth = Real32.fromInt (windowWidth div 2)
-      val halfHeight = Real32.fromInt (windowHeight div 2)
-      val lst = helpToVector
-        (#triangles app, [], windowWidth, windowHeight, halfWidth, halfHeight)
-    in
-      Vector.concat lst
-    end
-end
diff --git a/functional-core/file/parse-file.sml b/functional-core/file/parse-file.sml
deleted file mode 100644
index 3052b3a..0000000
--- a/functional-core/file/parse-file.sml
+++ /dev/null
@@ -1,135 +0,0 @@
-signature PARSE_FILE =
-sig
-  val parseLine: string -> AppType.triangle option
-end
-
-structure ParseFile :> PARSE_FILE =
-struct
-  datatype triangle_token =
-    X
-  | Y
-  | R
-  | G
-  | B
-  | COORD of Real32.real
-  | UNKNOWN of string
-
-  val zero: Real32.real = 0.0
-
-  fun extractTriangle lst =
-    case lst of
-      [ X
-      , COORD x1
-      , Y
-      , COORD y1
-
-      , X
-      , COORD x2
-      , Y
-      , COORD y2
-
-      , X
-      , COORD x3
-      , Y
-      , COORD y3
-      ] =>
-        (* file format not specifying any colours *)
-        SOME
-          { x1 = x1
-          , y1 = y1
-          , x2 = x2
-          , y2 = y2
-          , x3 = x3
-          , y3 = y3
-          , r = zero
-          , g = zero
-          , b = zero
-          }
-    | [ X
-      , COORD x1
-      , Y
-      , COORD y1
-
-      , X
-      , COORD x2
-      , Y
-      , COORD y2
-
-      , X
-      , COORD x3
-      , Y
-      , COORD y3
-
-      , R
-      , COORD r
-      , G
-      , COORD g
-      , B
-      , COORD b
-      ] =>
-        (* file format specifying rgb *)
-        SOME
-          { x1 = x1
-          , y1 = y1
-          , x2 = x2
-          , y2 = y2
-          , x3 = x3
-          , y3 = y3
-          , r = r
-          , g = g
-          , b = b
-          }
-    | _ => NONE
-
-  fun tokeniseString str =
-    if str = "x" then
-      X
-    else if str = "y" then
-      Y
-    else if str = "r" then
-      R
-    else if str = "g" then
-      G
-    else if str = "b" then
-      B
-    else
-      case Real32.fromString str of
-        SOME num => COORD num
-      | NONE => UNKNOWN str
-
-  fun helpParseLine (line, pos, acc, wordStartPos) =
-    if pos = String.size line then
-      List.rev acc
-    else
-      let
-        val chr = String.sub (line, pos)
-      in
-        if Char.isSpace chr then
-          if pos > 0 andalso Char.isSpace (String.sub (line, pos - 1)) then
-            (* if previous character is space, just proceed to next character *)
-            helpParseLine (line, pos + 1, acc, wordStartPos)
-          else
-            let
-              (* current character is space, but previous character is not, 
-               * which means we have some text to substring and tokenise 
-               * before proceeding to next character *)
-              val strToken =
-                String.substring (line, wordStartPos, pos - wordStartPos)
-              val token = tokeniseString strToken
-            in
-              helpParseLine (line, pos + 1, token :: acc, pos)
-            end
-        else if pos > 0 andalso Char.isSpace (String.sub (line, pos - 1)) then
-          (* previous character was space but current character is not,
-           * meaning that we have hit the start of a new word *)
-          helpParseLine (line, pos + 1, acc, pos)
-        else
-          (* just proceed to next character *)
-          helpParseLine (line, pos + 1, acc, wordStartPos)
-      end
-
-  fun parseLine line =
-    let val lst = helpParseLine (line, 0, [], 0)
-    in extractTriangle lst
-    end
-end
diff --git a/message-types/draw-msg.sml b/message-types/draw-msg.sml
index e4c8f34..f063d64 100644
--- a/message-types/draw-msg.sml
+++ b/message-types/draw-msg.sml
@@ -2,12 +2,12 @@ structure DrawMessage =
 struct
   datatype t =
     DRAW_DOT of Real32.real vector
-  | DRAW_TRIANGLES_AND_DOTS of
-      {triangles: Real32.real vector, dots: Real32.real vector}
-  | DRAW_TRIANGLES_AND_RESET_DOTS of Real32.real vector
+  | DRAW_SQUARES_AND_DOTS of
+      {squares: Real32.real vector, dots: Real32.real vector}
+  | DRAW_SQUARES_AND_RESET_DOTS of Real32.real vector
   | DRAW_GRAPH of Real32.real vector
-  | RESIZE_TRIANGLES_DOTS_AND_GRAPH of
-      { triangles: Real32.real vector
+  | RESIZE_SQUARES_DOTS_AND_GRAPH of
+      { squares: Real32.real vector
       , graphLines: Real32.real vector
       , dots: Real32.real vector
       }
diff --git a/message-types/file-msg.sml b/message-types/file-msg.sml
index 674fde6..02156db 100644
--- a/message-types/file-msg.sml
+++ b/message-types/file-msg.sml
@@ -1,9 +1,9 @@
 structure FileMessage =
 struct
   datatype t =
-    SAVE_TRIANGLES of AppType.triangle list
-  | LOAD_TRIANGLES
-  | EXPORT_TRIANGLES of AppType.triangle list
+    SAVE_SQUARES of int vector vector
+  | LOAD_SQUARES
+  | EXPORT_SQUARES of int vector vector
   | LOAD_FILES of string
   | SELECT_PATH of string
 end
diff --git a/message-types/input-msg.sml b/message-types/input-msg.sml
index e8a21aa..417a501 100644
--- a/message-types/input-msg.sml
+++ b/message-types/input-msg.sml
@@ -22,8 +22,9 @@ struct
   | ARROW_DOWN
   | KEY_ENTER
   | KEY_SPACE
-  | USE_TRIANGLES of AppType.triangle list
-  | TRIANGLES_LOAD_ERROR
+  | USE_SQUARES of
+      {squares: int vector vector, canvasWidth: int, canvasHeight: int}
+  | SQUARES_LOAD_ERROR
   | FILE_BROWSER_AND_PATH of
       {fileBrowser: AppType.file_browser_item vector, path: string}
 end
diff --git a/temp-squares/message-types/draw-msg.sml b/temp-squares/message-types/draw-msg.sml
deleted file mode 100644
index f063d64..0000000
--- a/temp-squares/message-types/draw-msg.sml
+++ /dev/null
@@ -1,16 +0,0 @@
-structure DrawMessage =
-struct
-  datatype t =
-    DRAW_DOT of Real32.real vector
-  | DRAW_SQUARES_AND_DOTS of
-      {squares: Real32.real vector, dots: Real32.real vector}
-  | DRAW_SQUARES_AND_RESET_DOTS of Real32.real vector
-  | DRAW_GRAPH of Real32.real vector
-  | RESIZE_SQUARES_DOTS_AND_GRAPH of
-      { squares: Real32.real vector
-      , graphLines: Real32.real vector
-      , dots: Real32.real vector
-      }
-  | CLEAR_DOTS
-  | DRAW_MODAL_TEXT of Real32.real vector
-end
diff --git a/temp-squares/message-types/file-msg.sml b/temp-squares/message-types/file-msg.sml
deleted file mode 100644
index 02156db..0000000
--- a/temp-squares/message-types/file-msg.sml
+++ /dev/null
@@ -1,9 +0,0 @@
-structure FileMessage =
-struct
-  datatype t =
-    SAVE_SQUARES of int vector vector
-  | LOAD_SQUARES
-  | EXPORT_SQUARES of int vector vector
-  | LOAD_FILES of string
-  | SELECT_PATH of string
-end
diff --git a/temp-squares/message-types/input-msg.sml b/temp-squares/message-types/input-msg.sml
deleted file mode 100644
index 417a501..0000000
--- a/temp-squares/message-types/input-msg.sml
+++ /dev/null
@@ -1,30 +0,0 @@
-structure InputMessage =
-struct
-  datatype t =
-    MOUSE_MOVE of {x: Real32.real, y: Real32.real}
-  | MOUSE_LEFT_CLICK
-  | MOUSE_LEFT_RELEASE
-  | RESIZE_WINDOW of {width: int, height: int}
-  | UNDO_ACTION
-  | REDO_ACTION
-  | KEY_R
-  | KEY_G
-  | KEY_B
-  | KEY_T
-  | KEY_CTRL_S
-  | KEY_CTRL_L
-  | KEY_CTRL_E
-  | KEY_CTRL_O
-  | NUM of int
-  | ARROW_UP
-  | ARROW_LEFT
-  | ARROW_RIGHT
-  | ARROW_DOWN
-  | KEY_ENTER
-  | KEY_SPACE
-  | USE_SQUARES of
-      {squares: int vector vector, canvasWidth: int, canvasHeight: int}
-  | SQUARES_LOAD_ERROR
-  | FILE_BROWSER_AND_PATH of
-      {fileBrowser: AppType.file_browser_item vector, path: string}
-end
diff --git a/temp-squares/message-types/update-msg.sml b/temp-squares/message-types/update-msg.sml
deleted file mode 100644
index 2b832b0..0000000
--- a/temp-squares/message-types/update-msg.sml
+++ /dev/null
@@ -1,2 +0,0 @@
-structure UpdateMessage =
-struct datatype t = DRAW of DrawMessage.t | FILE of FileMessage.t end
diff --git a/temp-squares/temp.mlb b/temp-squares/temp.mlb
deleted file mode 100644
index 8e65e7d..0000000
--- a/temp-squares/temp.mlb
+++ /dev/null
@@ -1,28 +0,0 @@
-$(SML_LIB)/basis/basis.mlb
-
-(* FUNCTIONAL CORE *)
-fcore/app-type.sml
-
-ann
-  "allowVectorExps true"
-in
-  fcore/ndc.sml
-  fcore/graph-lines.sml
-end
-
-fcore/click-points.sml
-fcore/app-init.sml
-fcore/app-with.sml
-
-message-types/draw-msg.sml
-message-types/file-msg.sml
-message-types/input-msg.sml
-message-types/update-msg.sml
-
-fcore/quad-tree.sml
-
-fcore/common-update.sml
-fcore/normal-mode.sml
-fcore/browse-mode.sml
-fcore/app-update.sml
-