XNA 4.0. Зачем при построении модели указывать координаты камеры

private void DrawModel(Model m)
{
Matrix[] transforms = new Matrix[m.Bones.Count];
m.CopyAbsoluteBoneTransformsTo(transforms);
world = Matrix.CreateTranslation(positionModel);
view = Matrix.CreateLookAt(new Vector3(0.0f, 0.0f, 150.0f),
Vector3.Zero, Vector3.Up);
proj = Matrix.CreatePerspectiveFieldOfView(FOV, aspectRatio,
nearClip, farClip);
foreach (ModelMesh mesh in m.Meshes)
{
foreach (BasicEffect effect in mesh.Effects)
{
effect.EnableDefaultLighting();
effect.World = transforms[mesh.ParentBone.Index] * world;
effect.View = view;
effect.Projection = proj;
}
mesh.Draw();
}
}

effect.View = view;
effect.Projection = proj;