diff --git a/fcore/wall.sml b/fcore/wall.sml
index 7c288f8..2aa1fc3 100644
--- a/fcore/wall.sml
+++ b/fcore/wall.sml
@@ -14,7 +14,9 @@ struct
 
   fun generateTree wallVec = helpGenerateTree (0, wallVec, QuadTree.empty)
 
-  fun helpGetDrawVec (pos, wallVec, acc, winWidth, winHeight) =
+  val preferredAspectRatio: Real32.real = 1920.0 / 1080.0
+
+  fun helpGetDrawVecPreferred (pos, wallVec, acc, winWidth, winHeight) =
     if pos = Vector.length wallVec then
       Vector.concat acc
     else
@@ -28,9 +30,87 @@ struct
           (x, y, width, height, winWidth, winHeight, 0.0, 0.0, 0.0)
         val acc = block :: acc
       in
-        helpGetDrawVec (pos + 1, wallVec, acc, winWidth, winHeight)
+        helpGetDrawVecPreferred (pos + 1, wallVec, acc, winWidth, winHeight)
+      end
+
+  (* when actual aspect ratio > preferredAspectRatio *)
+  fun helpGetDrawVecWider
+    (pos, wallVec, acc, winWidth, winHeight, ratio, yOffset) =
+    if pos = Vector.length wallVec then
+      Vector.concat acc
+    else
+      let
+        val wall = Vector.sub (wallVec, pos)
+        val {x, y, width, height, id = _} = wall
+
+        val x = Real32.fromInt x * ratio
+        val x = Real32.toInt IEEEReal.TO_NEAREST x
+
+        val y = Real32.fromInt y * ratio + yOffset
+        val y = Real32.toInt IEEEReal.TO_NEAREST y
+
+        val width = Real32.fromInt width * ratio
+        val height = Real32.fromInt height * ratio
+
+        val block = Block.lerp
+          (x, y, width, height, winWidth, winHeight, 0.0, 0.0, 0.0)
+        val acc = block :: acc
+      in
+        helpGetDrawVecWider
+          (pos + 1, wallVec, acc, winWidth, winHeight, ratio, yOffset)
+      end
+
+  (* when actual aspect ratio < preferredAspectRatio *)
+  fun helpGetDrawVecTaller
+    (pos, wallVec, acc, winWidth, winHeight, ratio, xOffset) =
+    if pos = Vector.length wallVec then
+      Vector.concat acc
+    else
+      let
+        val wall = Vector.sub (wallVec, pos)
+        val {x, y, width, height, id = _} = wall
+
+        val x = Real32.fromInt x * ratio + xOffset
+        val x = Real32.toInt IEEEReal.TO_NEAREST x
+
+        val y = Real32.fromInt y * ratio
+        val y = Real32.toInt IEEEReal.TO_NEAREST y
+
+        val width = Real32.fromInt width * ratio
+        val height = Real32.fromInt height * ratio
+
+        val block = Block.lerp
+          (x, y, width, height, winWidth, winHeight, 0.0, 0.0, 0.0)
+        val acc = block :: acc
+      in
+        helpGetDrawVecTaller
+          (pos + 1, wallVec, acc, winWidth, winHeight, ratio, xOffset)
       end
 
   fun getDrawVec (wallVec, width, height) =
-    helpGetDrawVec (0, wallVec, [], width, height)
+    let
+      val wratio = width / 1920.0
+      val hratio = height / 1080.0
+    in
+      if wratio < hratio then
+        let
+          val scale = 1080.0 * wratio
+          val yOffset =
+            if height > scale then (height - scale) / 2.0
+            else if height < scale then (scale - height) / 2.0
+            else 0.0
+        in
+          helpGetDrawVecWider (0, wallVec, [], width, height, wratio, yOffset)
+        end
+      else
+        let
+          val scale = 1920.0 * hratio
+          val xOffset =
+            if width > scale then (width - scale) / 2.0
+            else if width < scale then (scale - width) / 2.0
+            else 0.0
+        in
+          helpGetDrawVecTaller (0, wallVec, [], width, height, hratio, xOffset)
+        end
+    end
 end