Displayrand: Difference between revisions

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"deprecate" displayrand.... this needs more research
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>.

Latest revision as of 12:52, 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.