Used ARB extensions for occlusion queries in IECoreGL::Selector.
Used ARB extensions for occlusion queries in IECoreGL::Selector.

The non-extension form is only available in OpenGL 3.

lento/cortex,appleseedhq/cortex,davidsminor/cortex,davidsminor/cortex,hradec/cortex,lento/cortex,hradec/cortex,appleseedhq/cortex,davidsminor/cortex,goddardl/cortex,davidsminor/cortex,appleseedhq/cortex,lento/cortex,goddardl/cortex,goddardl/cortex,hradec/cortex