diff --git a/dot-to-dot b/dot-to-dot
index e45a96b..b9f3e3a 100755
Binary files a/dot-to-dot and b/dot-to-dot differ
diff --git a/dot-to-dot.mlb b/dot-to-dot.mlb
index f763b46..3b02815 100644
--- a/dot-to-dot.mlb
+++ b/dot-to-dot.mlb
@@ -14,16 +14,11 @@ message-types/input-msg.sml
 message-types/draw-msg.sml
 
 functional-core/app-type.sml
-ann
-  "allowVectorExps true"
-in
-  functional-core/app-update.sml
-end
-
 ann
   "allowVectorExps true"
 in
   imperative-shell/constants.sml
+  functional-core/app-update.sml
   imperative-shell/app-draw.sml
 end
 
diff --git a/functional-core/app-update.sml b/functional-core/app-update.sml
index 91303c3..7665e6f 100644
--- a/functional-core/app-update.sml
+++ b/functional-core/app-update.sml
@@ -26,7 +26,8 @@ struct
     end
 
   local
-    val clickPoints = genClickPoints (500, 500)
+    val clickPoints = 
+      genClickPoints (Constants.windowWidth, Constants.windowHeight)
 
     fun getVerticalClickPos (idx, horizontalPos, mouseX, mouseY, r, g, b) =
       if idx = Vector.length clickPoints then
@@ -40,12 +41,14 @@ struct
               (idx + 1, horizontalPos, mouseX, mouseY, r, g, b)
           else
             let
-              val hpos = horizontalPos - 250.0
-              val vpos = ~(curVerticalPos - 250.0)
-              val left = (hpos - 5.0) / 250.0
-              val right = (hpos + 5.0) / 250.0
-              val bottom = (vpos - 5.0) / 250.0
-              val top = (vpos + 5.0) / 250.0
+              val halfWidth = Real32.fromInt (Constants.windowWidth div 2)
+              val halfHeight = Real32.fromInt (Constants.windowHeight div 2)
+              val hpos = horizontalPos - halfWidth
+              val vpos = ~(curVerticalPos - halfHeight)
+              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
               #[ left, bottom, r, g, b
                , right, bottom, r, g, b
diff --git a/imperative-shell/constants.sml b/imperative-shell/constants.sml
index 52f7eaa..355b951 100644
--- a/imperative-shell/constants.sml
+++ b/imperative-shell/constants.sml
@@ -1,5 +1,8 @@
 structure Constants =
 struct
+  val windowWidth = 900
+  val windowHeight = 900
+
   val graphVertexShaderString =
     "#version 300 es\n\
     \layout (location = 0) in vec2 apos;\n\
diff --git a/imperative-shell/shell.sml b/imperative-shell/shell.sml
index 9bb9907..9f957f1 100644
--- a/imperative-shell/shell.sml
+++ b/imperative-shell/shell.sml
@@ -9,7 +9,8 @@ struct
       val _ = Glfw.windowHint (Glfw.CONTEXT_VERSION_MAJOR (), 3)
       val _ = Glfw.windowHint (Glfw.DEPRECATED (), Glfw.FALSE ())
       val _ = Glfw.windowHint (Glfw.SAMPLES (), 4)
-      val window = Glfw.createWindow (500, 500, "MLton - box x box")
+      val window = 
+        Glfw.createWindow (Constants.windowWidth, Constants.windowHeight, "MLton - dot to dot")
       val _ = Glfw.makeContextCurrent window
       val _ = Gles3.loadGlad ()