allow creation on remote (X11) displays

[umlaeute]

with X11 it is possible to open a window on a remote display.

i have a some users who are using this, allowing them to display the control interface on one computer, and the openGL output window on another computer - all from within one application. and they might even decide to switch the target display during runtime (obviously destroying the window first, then re-creating it on another DISPLAY)

now that we have switched our default windowing backend from GLX to GLFW, this is no longer possible.

i did a quick check to see whether I could trick glfw by setting the DISPLAY variable before calling glfwCreateWindow(), but alas! this does not work (as glfw requests the display only once, during glfwInit(), which can only be called once).

would it be possible to add a (possibly X11 specific) Window creation hint (e.g. glfwWindowHintString(GLFW_DISPLAY, ":0")) to allow setting a target display?

i'm aware that currently glfw maintains a global display for all its windows....