enum vzInternalTextureFormat {
   VZ_DEFAULT_INTERNAL_FORMAT    = -1,
   VZ_INTENSITY8                 = GL_INTENSITY8, 
   VZ_INTENSITY12                = GL_INTENSITY12,
   VZ_RGB4                       = GL_RGB4, 
   VZ_RGB5                       = GL_RGB5, 
   VZ_INTENSITY16                = GL_INTENSITY16,
   VZ_LUMINANCE8_ALPHA8          = GL_LUMINANCE8_ALPHA8,
   VZ_LUMINANCE12_ALPHA4         = GL_LUMINANCE12_ALPHA4,
   VZ_RGBA4                      = GL_RGBA4,
   VZ_RGB5_A1                    = GL_RGB5_A1,
   VZ_LUMINANCE12_ALPHA12        = GL_LUMINANCE12_ALPHA12,
   VZ_RGB8                       = GL_RGB8,
   VZ_RGB10                      = GL_RGB10,
   VZ_LUMINANCE16_ALPHA16        = GL_LUMINANCE16_ALPHA16,
   VZ_RGBA8                      = GL_RGBA8,
   VZ_RGB10_A2                   = GL_RGB10_A2,
   VZ_RGB12                      = GL_RGB12, 
   VZ_RGBA12                     = GL_RGBA12,
   VZ_RGB16                      = GL_RGB16,
   VZ_DUAL_INTENSITY8            = GL_DUAL_INTENSITY8_SGIS,
   VZ_DUAL_LUMINANCE_ALPHA4      = GL_DUAL_LUMINANCE_ALPHA4_SGIS,
   VZ_QUAD_INTENSITY4            = GL_QUAD_INTENSITY4_SGIS,
   VZ_INTENSITY_FLOAT16          = GL_INTENSITY_FLOAT16_ATI,
   VZ_LUMINANCE_ALPHA_FLOAT16    = GL_LUMINANCE_ALPHA_FLOAT16_ATI,
   VZ_RGB_FLOAT16                = GL_RGB_FLOAT16_ATI,
   VZ_RGBA_FLOAT16               = GL_RGBA_FLOAT16_ATI,
   VZ_INTENSITY_FLOAT32          = GL_INTENSITY_FLOAT32_ATI,
   VZ_LUMINANCE_ALPHA_FLOAT32    = GL_LUMINANCE_ALPHA_FLOAT32_ATI,
   VZ_RGB_FLOAT32                = GL_RGB_FLOAT32_ATI,
   VZ_RGBA_FLOAT32               = GL_RGBA_FLOAT32_ATI
};