a design problem

class Material
{
public:
    /** Constructor - use resource manager's create method rather than this.
       */
	Material();
    ~Material();
    Material& operator=( const Material& rhs );
  
	bool isTransparent(void) const;
 
    // -------------------------------------------------------------------------------
		  D3DCOLORVALUE & ambient();
	const D3DCOLORVALUE & diffuse();
	const D3DCOLORVALUE & specular();
    const D3DCOLORVALUE & emissive();
    void  power();

	void setAmbient(const D3DXCOLOR& ambient);
	void setDiffuse(const D3DXCOLOR& diffuse);
	void setSpecular(const D3DXCOLOR& specular);
    void setEmissive(const D3DXCOLOR& selfIllum);
	void addEmissive(const D3DXCOLOR& selfIllum);
	void addDiffuse(const D3DXCOLOR& diffuse);
	void addAmbient(const D3DXCOLOR& ambient);
	void setPower(float val);
	void addBright();
	void subBright();

	D3DMATERIAL9 &material9();
	void setMaterial9( D3DMATERIAL9* );

	IDirect3DTexture9 * texture() const;
	void setTexture(IDirect3DTexture9 * t);

	void setLightingEnabled(bool enabled);

protected:
	std::string				m_name;
	bool					m_transparent;
	bool					m_lightEnabled;

	D3DMATERIAL9			m_dxMaterial;
	IDirect3DTexture9		*m_texture;

	/** Internal method which sets the material up from the default settings.
	*/
	void init(void);

	/** Overridden from Resource.
	*/
};