timerefresh can be used for benchmarking. it skips over all the irrelevent client/server/etc code and measures just your cards *SwapBuffers call.

Its important to know where the time is spent so you can target optimisations more effectively.
But it is a C coder's command. I'm not sure a mapper would care.
envmap can be useful. Specifically, it can be useful for generating cubemap images. Yay skyboxes...
But more practically, if you ever support certain renderer effects like cubemap reflections or rtlights, the envmap command is the only real way to generate such cubemaps.
Obviously, this only applies if you actually support rendering various such cubemaps. For every other engine is a bit useless.
Its a mapper command in those cases.
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