public void Rotate(float angle)
{
matrix = AffineMatrix.MultMatrices(AffineMatrix.RotateMatrix(angle), matrix);
}
public void Scale(float width, float height)
{
matrix = AffineMatrix.MultMatrices(AffineMatrix.ScaleMatrix(width, height), matrix);
}
public void Translate(float dx, float dy)
{
matrix = AffineMatrix.MultMatrices(AffineMatrix.TranslateMatrix(dx, dy), matrix);
}