enum
    {
        kTextureDiffuse = 0,
        kTextureNormal,
        kTextureEnvironmentMask,
        kTextureSubsurfaceTint = kTextureEnvironmentMask,
        kTextureGlowMap,
        kTextureDetailMap = kTextureGlowMap,
        kTextureHeight,
        kTextureEnvironment,
        kTextureMultilayer,
        kTextureBacklightMask,
        kTextureSpecular = kTextureBacklightMask,
        kTextureUnused08,
        kNumTextures = 9
    };