skytexture fix


git-svn-id: svn://svn.tuxfamily.org/svnroot/tesseract/main@1636 b412e182-2ed4-4078-95c4-27dc59f57fa9
remove unused extern


git-svn-id: svn://svn.tuxfamily.org/svnroot/tesseract/main@1637 b412e182-2ed4-4078-95c4-27dc59f57fa9
silence some unused variable warnings


git-svn-id: svn://svn.tuxfamily.org/svnroot/tesseract/main@1638 b412e182-2ed4-4078-95c4-27dc59f57fa9