Add hint for auto mipmap generation in OpenGL.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@2078 dfc29bdd-3216-0410-991c-e03cc46cb475

source/Irrlicht/COpenGLTexture.cpp

@@ -184,14 +184,22 @@ void COpenGLTexture::copyTexture(bool newTexture)
 
 	if (newTexture)
 	{
-		#ifndef DISABLE_MIPMAPPING
+#ifndef DISABLE_MIPMAPPING
+#ifdef GL_SGIS_generate_mipmap
 		if (HasMipMaps && Driver->queryFeature(EVDF_MIP_MAP_AUTO_UPDATE))
 		{
+			if (Driver->getTextureCreationFlag(ETCF_OPTIMIZED_FOR_SPEED))
+				glHint(GENERATE_MIPMAP_HINT_SGIS, GL_FASTEST);
+			else if (Driver->getTextureCreationFlag(ETCF_OPTIMIZED_FOR_QUALITY))
+				glHint(GENERATE_MIPMAP_HINT_SGIS, GL_NICEST);
+			else
+				glHint(GENERATE_MIPMAP_HINT_SGIS, GL_DONT_CARE);
 			// automatically generate and update mipmaps
 			glTexParameteri( GL_TEXTURE_2D, GL_GENERATE_MIPMAP, GL_TRUE );
 			AutomaticMipmapUpdate=true;
 		}
 		else
+#endif
 		{
 			AutomaticMipmapUpdate=false;
 			regenerateMipMapLevels();