Difference between revisions of "Displayrand"

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(mention that displayrand uses the "system" PRNG (which is libc rand() with potential truncation now, but that's an implementation detail))
 
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'''displayrand''' <gamevar><br>
'''displayrand''' <gamevar><br>
generates a random number between 0 and a system-specific maximum value and assigns it to <gamevar>. Specifically, the maximum values may differ between EDuke32 builds produced with the GCC and MSVC compilers, and/or operating systems. Use of this function is thus discouraged.
generates a random number between 0 and a certain maximum value (using the system PRNG in a not further specified fashion) and assigns it to <gamevar>. With EDuke32 revisions prior to r2105, the maximum values may differ between EDuke32 builds produced with the GCC and MSVC compilers, and/or operating systems. Revisions r2105 and up always generate numbers from 0 to 32767 (inclusive).


'''displayrandvar''' <gamevar> <maxvalue_constant><br>
'''displayrandvar''' <gamevar> <maxvalue_constant><br>
'''displayrandvarvar''' <gamevar> <maxvalue_gamevar>
'''displayrandvarvar''' <gamevar> <maxvalue_gamevar>


The '''displayrandvar''' commands limit the number to be between 0 and <maxvalue>.
The '''displayrandvar''' commands limit the number to be between 0 and <maxvalue>, inclusive.


'''displayrandvarvar''' takes a [[gamevar]] rather than a constant or a [[define]]d label for <maxvalue>.
'''displayrandvarvar''' takes a [[gamevar]] rather than a constant or a [[define]]d label for <maxvalue>.


This function must ONLY be used in unsynchronized code. Use in syncronized code is almost certain to cause desyncs.
Since this function is sync safe, it can be used in unsynchronized code.


See [[randomseed]].
See [[randomseed]].

Latest revision as of 11:52, 21 March 2012

displayrand <gamevar>
generates a random number between 0 and a certain maximum value (using the system PRNG in a not further specified fashion) and assigns it to <gamevar>. With EDuke32 revisions prior to r2105, the maximum values may differ between EDuke32 builds produced with the GCC and MSVC compilers, and/or operating systems. Revisions r2105 and up always generate numbers from 0 to 32767 (inclusive).

displayrandvar <gamevar> <maxvalue_constant>
displayrandvarvar <gamevar> <maxvalue_gamevar>

The displayrandvar commands limit the number to be between 0 and <maxvalue>, inclusive.

displayrandvarvar takes a gamevar rather than a constant or a defined label for <maxvalue>.

Since this function is sync safe, it can be used in unsynchronized code.

See randomseed.