I was reading this programming tutorial about making a listener loop, a non-ending loop in a program that does nothing but continually check for a key press
for as long as the program runs. It was demonstrated that this one loop not only slowed the program down by taking up all the processor time, but it actually
slowed down other apps that were being run at the same time. So my question is, how big an issue are forever loops in programs as far as speed is concerned. I
would think it could be a huge drain on speed if these loops were not slowed down by having some kind of wait state to activate them at a more controllable
rate.
question about loops
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 arquebus |
question about loops |
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(07/08/09 14:16:15) |
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deerwood |
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(07/08/09 18:28:33) |
arquebus: >> I was reading this programming tutorial about making a listener loop ... Can you post the link to that tut; do you talk about Erlang or some other language? |
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arquebus |
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(07/08/09 21:10:50) |
deerwood wrote: Deerwood- I cant remember exactly which book or tutorial in which I was reading that, I think it was the book "MUD Game Programming" which is now out of print. I am sure it was refering to theC++ programming language so the concept does not apply directly to Erlang which can avoid the problem to some extent by its concurrent mechanisms. But since people on this forum work both on Erlang compiler and porting OpenGL/SDL librarys to Wings, I would think that they are well versed on whether forever loops are a problem or not.
Last Edited By: arquebus
07/08/09 21:51:52.
Edited 1 times.
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 bjorng |
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(07/08/09 21:45:40) |
Yes, that type of loops are bad and they should be avoided. Unfortunately, SDL/ESDL forces us to use such a busy polling loop to receive events.
What I have done is to wait 10 milli-seconds between polls if the Wings window is active. If the Wings window has been iconified or if the mouse cursor is outside the Wings window, I use longer times between polls. See wings_io:wait_for_event/1 to see how it's done. |
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