/usr/include/obs/graphics/ is in libobs-dev 0.15.4+dfsg1-1+b1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/obs/graphics/axisang.h
/usr/include/obs/graphics/bounds.h
/usr/include/obs/graphics/device-exports.h
/usr/include/obs/graphics/effect-parser.h
/usr/include/obs/graphics/effect.h
/usr/include/obs/graphics/graphics-internal.h
/usr/include/obs/graphics/graphics.h
/usr/include/obs/graphics/image-file.h
/usr/include/obs/graphics/input.h
/usr/include/obs/graphics/libnsgif/
/usr/include/obs/graphics/libnsgif/libnsgif.h
/usr/include/obs/graphics/math-defs.h
/usr/include/obs/graphics/math-extra.h
/usr/include/obs/graphics/matrix3.h
/usr/include/obs/graphics/matrix4.h
/usr/include/obs/graphics/plane.h
/usr/include/obs/graphics/quat.h
/usr/include/obs/graphics/shader-parser.h
/usr/include/obs/graphics/vec2.h
/usr/include/obs/graphics/vec3.h
/usr/include/obs/graphics/vec4.h