XCB_GLX_GC_GL_VIEWPORT_BIT

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
extern (C)
alias XCB_GLX_GC_GL_VIEWPORT_BIT = xcb_glx_gc_t.XCB_GLX_GC_GL_VIEWPORT_BIT

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