diff --git a/GDP/D3D9/Mesh.cpp b/GDP/D3D9/Mesh.cpp
index a40bc28..0d979f6 100644
--- a/GDP/D3D9/Mesh.cpp
+++ b/GDP/D3D9/Mesh.cpp
@@ -28,6 +28,21 @@ UINT Mesh::init(IDirect3DDevice9* pD3DDevice)
 
 void Mesh::update(FLOAT dt)
 {
+    static FLOAT x = 0.0f;
+    static FLOAT y = 0.0f;
+    static FLOAT z = 0.0f;
+    static FLOAT pitch = 0.0f;
+    static FLOAT yaw = 0.0f;
+    static FLOAT roll = 0.0f;
+    static FLOAT scale = 1.0f;
+
+    yaw += 0.01f;
+
+    XMMATRIX translationMatrix = XMMatrixTranslation(x, y, z);
+    XMMATRIX rotationMatrix = XMMatrixRotationRollPitchYaw(pitch, yaw, roll);
+    XMMATRIX scaleMatrix = XMMatrixScaling(scale, scale, scale);
+
+    XMStoreFloat4x4(reinterpret_cast<XMFLOAT4X4*>(&_worldMatrix), scaleMatrix * rotationMatrix * translationMatrix);
 }
 
 void Mesh::render(IDirect3DDevice9* pD3DDevice)
diff --git a/GDP/D3D9/main.cpp b/GDP/D3D9/main.cpp
index 3900a51..0c09926 100644
--- a/GDP/D3D9/main.cpp
+++ b/GDP/D3D9/main.cpp
@@ -32,6 +32,7 @@ int WINAPI WinMain(
 	error = d3d.init(window.getWindowHandle(), width, height, isFullscreen);
 	CheckError(error);
 
+	// set render states
 	d3d.getDevice()->SetRenderState(D3DRS_CULLMODE, D3DCULL_CCW);
 
 	// 3. create a mesh