depends OPENGL &&
depends GLUT &&
optional_depends zlib "-DENABLE_ZLIB=on" "-DENABLE_ZLIB=off" "for zlib compression support" &&
optional_depends libpng "-DENABLE_PNG=on" "-DENABLE_PNG=off" "support for png images" &&
depends texlive &&
depends libxext &&
depends libx11 &&
depends libice

.