git-svn-id: svn://kolibrios.org@5171 a494cfbc-eb01-0410-851d-a64ba20cac60
git-svn-id: svn://kolibrios.org@5163 a494cfbc-eb01-0410-851d-a64ba20cac60
2) add function glClear git-svn-id: svn://kolibrios.org@5159 a494cfbc-eb01-0410-851d-a64ba20cac60