diff --git a/resources/chicken.png b/resources/chicken.png
new file mode 100644
index 0000000..a30f4cf
--- /dev/null
+++ b/resources/chicken.png
Binary files differ
diff --git a/resources/test.png b/resources/test.png
deleted file mode 100644
index a42be28..0000000
--- a/resources/test.png
+++ /dev/null
Binary files differ
diff --git a/src/main/java/JumpGame.java b/src/main/java/JumpGame.java
index 9026eae..caa33a5 100644
--- a/src/main/java/JumpGame.java
+++ b/src/main/java/JumpGame.java
@@ -1,5 +1,6 @@
 import entities.*;
 import models.IModel;
+import models.ModelType;
 import models.PlayerModel;
 import views.IView;
 import views.PlayerRenderer;
@@ -22,17 +23,18 @@
 
     //---------------------------------------------------------------
     // new
+    private int i = 0;
     private ArrayList<IView> views = new ArrayList<>();
     private ArrayList<IModel> models = new ArrayList<>();
 
-    private PlayerModel playerModel = new PlayerModel(ground);
-
     //---------------------------------------------------------------
     //---------------------------------------------------------------
     //
     public void gravity(double y) {
-        //    this.force.gravity(y);
-        //   this.time.gravity(y);
+//            this.force.gravity(y);
+//           this.time.gravity(y);
+        PlayerModel playerModel = (PlayerModel) models.get(ModelType.PlayerModel);
+        playerModel.updateGravity(y);
     }
 
     //---------------------------------------------------------------
@@ -43,7 +45,8 @@
         models.add(new PlayerModel(ground));
 
         // view
-        views.add(new PlayerRenderer("resources/test.png"));
+        views.add(new PlayerRenderer("resources/chicken.png", 0.5));
+
     }
 
     //---------------------------------------------------------------
@@ -54,6 +57,7 @@
         for (IModel model : models) {
             for (IView view : views) view.display(model);
         }
+
         // Modelの更新
         //
         // Space キーのインプット
diff --git a/src/main/java/Main.java b/src/main/java/Main.java
index 15c69c2..296f047 100644
--- a/src/main/java/Main.java
+++ b/src/main/java/Main.java
@@ -9,6 +9,7 @@
 
 public class Main {
 
+    private long variableYieldTime, lastTime;
     // ウィンドウハンドル
     private long hWnd;
 
@@ -44,6 +45,7 @@
 
             glfwSwapBuffers(hWnd); // バッファのスワップ
             glfwPollEvents(); // 入力とかイベントの取得
+
         }
 
         // 終了処理
@@ -80,13 +82,15 @@
 
         // ウィンドウの表示
         glfwShowWindow(hWnd);
+
+
     }
 
     //---------------------------------------------------------------
     // 描画プロセス初期化
     private void initRender() {
         GL.createCapabilities();
-        glClearColor(0.0f, 0.0f, 0.0f, 0.0f); // 背景色設定
+        glClearColor(1.0f, 1.0f, 1.0f, 1.0f); // 背景色設定
 
         // OpenGLの初期化
         glEnable(GL_TEXTURE_2D); // 二次元テクスチャの有効化
@@ -99,5 +103,46 @@
     public void delete() {
         jumpGame.delete();
     }
+
+    //---------------------------------------------------------------
+    //
+    private void sync(int fps) {
+        if (fps <= 0) return;
+
+        long sleepTime = 1000000000 / fps; // nanoseconds to sleep this frame
+        // yieldTime + remainder micro & nano seconds if smaller than sleepTime
+        long yieldTime = Math.min(sleepTime, variableYieldTime + sleepTime % (1000*1000));
+        long overSleep = 0; // time the sync goes over by
+
+        try {
+            while (true) {
+                long t = System.nanoTime() - lastTime;
+
+                if (t < sleepTime - yieldTime) {
+                    Thread.sleep(1);
+                }else if (t < sleepTime) {
+                    // burn the last few CPU cycles to ensure accuracy
+                    Thread.yield();
+                }else {
+                    overSleep = t - sleepTime;
+                    break; // exit while loop
+                }
+            }
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }finally{
+            lastTime = System.nanoTime() - Math.min(overSleep, sleepTime);
+
+            // auto tune the time sync should yield
+            if (overSleep > variableYieldTime) {
+                // increase by 200 microseconds (1/5 a ms)
+                variableYieldTime = Math.min(variableYieldTime + 200*1000, sleepTime);
+            }
+            else if (overSleep < variableYieldTime - 200*1000) {
+                // decrease by 2 microseconds
+                variableYieldTime = Math.max(variableYieldTime - 2*1000, 0);
+            }
+        }
+    }
     //---------------------------------------------------------------
 }
\ No newline at end of file
diff --git a/src/main/java/entities/Image2D.java b/src/main/java/entities/Image2D.java
index 58bc4fd..b992457 100644
--- a/src/main/java/entities/Image2D.java
+++ b/src/main/java/entities/Image2D.java
@@ -31,8 +31,7 @@
         if (tex != null)
             wh = new Pair<>((double) tex.getWidth(), (double) tex.getHeight());
         else
-            wh = new Pair<>(30d, 30d);
-
+            wh = new Pair<>(32d, 20d);
         rotation = 0.0;
         scale = 1.0;
         alpha = 1.0;
@@ -49,6 +48,10 @@
         this.position = position;
     }
 
+    public void setScale(double scale) {
+        this.scale = scale;
+    }
+
     //---------------------------------------------------------------
     //---------------------------------------------------------------
     //
diff --git a/src/main/java/entities/Sprite.java b/src/main/java/entities/Sprite.java
index 0566eb5..37421b6 100644
--- a/src/main/java/entities/Sprite.java
+++ b/src/main/java/entities/Sprite.java
@@ -7,6 +7,7 @@
 public class Sprite {
 
     private Pair<Double> positionValue;
+    private double scaleValue;
     private Texture texture;
     private Image2D img;
 
@@ -26,10 +27,15 @@
         this.positionValue = positionValue;
     }
 
+    public void setScaleValue(double scaleValue) {
+        this.scaleValue = scaleValue;
+    }
+
     //---------------------------------------------------------------
     //---------------------------------------------------------------
     //
     public void draw() {
+        img.setScale(scaleValue);
         img.setPosition(positionValue);
         img.draw();
     }
diff --git a/src/main/java/entities/Velocity.java b/src/main/java/entities/Velocity.java
index 9f218ea..22e9bf1 100644
--- a/src/main/java/entities/Velocity.java
+++ b/src/main/java/entities/Velocity.java
@@ -2,11 +2,11 @@
 
 
 public class Velocity {
-    private Pair<Double> moveValue;
-    private Pair<Double> accelerationValue;
+    private Pair<Double> moveValue = new Pair<>(0d, 0d);
+    private Pair<Double> accelerationValue = new Pair<>(0d, 0d);
     private Position position;
     private Onground onground;
-    private Pair<Double> value;
+    private Pair<Double> value = new Pair<>(0d, 0d);
 
     //---------------------------------------------------------------
     //---------------------------------------------------------------
diff --git a/src/main/java/models/ModelType.java b/src/main/java/models/ModelType.java
new file mode 100644
index 0000000..604df21
--- /dev/null
+++ b/src/main/java/models/ModelType.java
@@ -0,0 +1,17 @@
+package models;
+
+//---------------------------------------------------------------
+// モデルのタイプ識別
+public class ModelType {
+
+    public static final int PlayerModel = 0;
+    public static final int GroundModel = 1;
+    public static final int GameModel = 2;
+
+    //---------------------------------------------------------------
+    //---------------------------------------------------------------
+    private ModelType() {
+
+    }
+    //---------------------------------------------------------------
+}
diff --git a/src/main/java/models/PlayerModel.java b/src/main/java/models/PlayerModel.java
index bbdb8cc..ecc41f8 100644
--- a/src/main/java/models/PlayerModel.java
+++ b/src/main/java/models/PlayerModel.java
@@ -40,6 +40,10 @@
     public void jump() {
         this.move.moveY(jumpPower);
     }
-    //---------------------------------------------------------------
 
+    //---------------------------------------------------------------
+    //
+    public void updateGravity(double gravity) {
+        this.force.gravity(gravity);
+    }
 }
diff --git a/src/main/java/views/PlayerRenderer.java b/src/main/java/views/PlayerRenderer.java
index 4da715c..559f06f 100644
--- a/src/main/java/views/PlayerRenderer.java
+++ b/src/main/java/views/PlayerRenderer.java
@@ -11,8 +11,9 @@
 
     //---------------------------------------------------------------
     //---------------------------------------------------------------
-    public PlayerRenderer(String path) {
+    public PlayerRenderer(String path, double scale) {
         this.sprite = new Sprite(path);
+        this.sprite.setScaleValue(scale);
     }
 
     //---------------------------------------------------------------