diff --git a/dotscape b/dotscape
index fa3d28a..d2cbfdc 100755
Binary files a/dotscape and b/dotscape differ
diff --git a/fcore/app-with.sml b/fcore/app-with.sml
index b21ef16..950728f 100644
--- a/fcore/app-with.sml
+++ b/fcore/app-with.sml
@@ -895,6 +895,68 @@ struct
       }
     end
 
+  fun canvasHeight (app: app_type, newCanvasHeight) =
+    let
+      val
+        { mode
+        , canvasHeight = _
+        , canvasWidth
+        , squares
+        , arrowX
+        , arrowY
+        , windowWidth
+        , windowHeight
+        , xClickPoints
+        , yClickPoints
+
+        , showGraph
+        , mouseX
+        , mouseY
+        , openFilePath
+        , fileBrowser
+        , fileBrowserIdx
+        , r
+        , g
+        , b
+        , a
+        , modalNum
+        , undo
+        , redo
+        } = app
+
+      val squares = changeSquaresSize (squares, canvasWidth, newCanvasHeight)
+      val arrowY = Int.min (arrowY, newCanvasHeight)
+      val (xClickPoints, yClickPoints) =
+        ClickPoints.generate
+          (windowWidth, windowHeight, canvasWidth, newCanvasHeight)
+    in
+      { mode = mode
+      , canvasHeight = newCanvasHeight
+      , canvasWidth = canvasWidth
+      , arrowX = arrowX
+      , mouseX = mouseX
+      , mouseY = mouseY
+      , squares = squares
+      , arrowY = arrowY
+      , windowWidth = windowWidth
+      , windowHeight = windowHeight
+      , xClickPoints = xClickPoints
+      , yClickPoints = yClickPoints
+
+      , showGraph = showGraph
+      , openFilePath = openFilePath
+      , fileBrowser = fileBrowser
+      , fileBrowserIdx = fileBrowserIdx
+      , r = r
+      , g = g
+      , b = b
+      , a = a
+      , modalNum = 0
+      , undo = undo
+      , redo = redo
+      }
+    end
+
 (* todo: 
   fun useSquaresAndSetNormalMode (app: app_type, squares, canvasWidth, canvasHeight) =
 *)
diff --git a/fcore/normal-mode.sml b/fcore/normal-mode.sml
index 917f7a7..672d87d 100644
--- a/fcore/normal-mode.sml
+++ b/fcore/normal-mode.sml
@@ -252,10 +252,10 @@ struct
   fun updateBlue model = (AppWith.b model, [])
   fun updateAlpha model = (AppWith.a model, [])
 
-  fun updateCanvasWidth model =
+  fun updateCanvas (model, canvasWidth, canvasHeight) =
     let
-      val newCanvasWidth = #modalNum model
-      val model = AppWith.canvasWidth (model, newCanvasWidth)
+      val newCanvaidth = #modalNum model
+      val model = AppWith.canvasWidth (model, canvasWidth)
 
       val
         { arrowX
@@ -263,15 +263,13 @@ struct
         , windowWidth
         , windowHeight
         , squares
-        , canvasWidth
-        , canvasHeight
         , xClickPoints
         , yClickPoints
         , showGraph
         , ...
         } = model
 
-      val dotVec = getDotVecFromIndices (model, #arrowX model, #arrowY model)
+      val dotVec = getDotVecFromIndices (model, arrowX, arrowY)
       val graphLines =
         if showGraph then GraphLines.generate model else Vector.fromList []
 
@@ -294,6 +292,23 @@ struct
       (model, [DRAW msg])
     end
 
+  fun updateCanvasWidth model =
+    let
+      val newCanvasWidth = #modalNum model
+      val (model as {canvasWidth, canvasHeight, ...}) =
+        AppWith.canvasWidth (model, newCanvasWidth)
+    in
+      updateCanvas (model, canvasWidth, canvasHeight)
+    end
+
+  fun updateCanvasHeight model =
+    let
+      val newCanvasHeight = #modalNum model
+      val (model as {canvasWidth, canvasHeight, ...}) =
+        AppWith.canvasHeight (model, newCanvasHeight)
+    in
+      updateCanvas (model, canvasWidth, canvasHeight)
+    end
 
   fun enterBrowseMode model =
     let
@@ -324,6 +339,7 @@ struct
     | KEY_B => updateBlue model
     | KEY_A => updateAlpha model
     | KEY_W => updateCanvasWidth model
+    | KEY_H => updateCanvasHeight model
     | RESIZE_WINDOW {width, height} => resizeWindow (model, width, height)
     | UNDO_ACTION => undoAction model
     | REDO_ACTION => redoAction model
diff --git a/ffi/glfw-input.c b/ffi/glfw-input.c
index 89acd59..8c93d06 100644
--- a/ffi/glfw-input.c
+++ b/ffi/glfw-input.c
@@ -21,6 +21,7 @@ int KEY_L = GLFW_KEY_L;
 int KEY_O = GLFW_KEY_O;
 int KEY_A = GLFW_KEY_A;
 int KEY_W = GLFW_KEY_W;
+int KEY_H = GLFW_KEY_H;
 
 int KEY_ENTER = GLFW_KEY_ENTER;
 int KEY_SPACE = GLFW_KEY_SPACE;
diff --git a/ffi/glfw-input.sml b/ffi/glfw-input.sml
index 84eed39..db5a3ab 100644
--- a/ffi/glfw-input.sml
+++ b/ffi/glfw-input.sml
@@ -59,6 +59,8 @@ struct
     _symbol "KEY_A" public : ( unit -> int ) * ( int -> unit );
   val (KEY_W, _) =
     _symbol "KEY_W" public : ( unit -> int ) * ( int -> unit );
+  val (KEY_H, _) =
+    _symbol "KEY_H" public : ( unit -> int ) * ( int -> unit );
 
   val (KEY_ENTER, _) =
     _symbol "KEY_ENTER" public : ( unit -> int ) * ( int -> unit );
diff --git a/imperative-shell/input-callbacks.sml b/imperative-shell/input-callbacks.sml
index 3c4a51a..8e54d12 100644
--- a/imperative-shell/input-callbacks.sml
+++ b/imperative-shell/input-callbacks.sml
@@ -76,6 +76,10 @@ struct
       key = Input.KEY_W () andalso action = Input.PRESS () andalso mods = 0
     then
       Mailbox.send (mailbox, KEY_W)
+    else if
+      key = Input.KEY_H () andalso action = Input.PRESS () andalso mods = 0
+    then
+      Mailbox.send (mailbox, KEY_H)
     else if
       key = Input.KEY_UP () andalso action <> Input.RELEASE ()
       andalso mods = 0x0
diff --git a/message-types/input-msg.sml b/message-types/input-msg.sml
index 9e859f6..b1f8033 100644
--- a/message-types/input-msg.sml
+++ b/message-types/input-msg.sml
@@ -13,6 +13,7 @@ struct
   | KEY_T
   | KEY_A
   | KEY_W
+  | KEY_H
   | KEY_CTRL_S
   | KEY_CTRL_L
   | KEY_CTRL_E