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Double Math Determinism

Discussion in 'Scripting' started by jpthek9, Feb 9, 2015.

  1. jpthek9

    jpthek9

    Joined:
    Nov 28, 2013
    Posts:
    944
    Will calculations on different platforms be precise enough to be used in a lockstep RTS game if the square root and trigonometry functions will be used extensively for games of up to 3 hours in length?
     
    Last edited: Feb 9, 2015
    jpthek9, Feb 9, 2015
    #1

  2. Todd-Wasson

    Todd-Wasson

    Joined:
    Aug 7, 2014
    Posts:
    1,077
    Can't say for sure, but I would be surprised if they did. Maybe someone else knows?
     
    Todd-Wasson, Feb 10, 2015
    #2

  3. Limyc

    Limyc

    Joined:
    Jan 27, 2013
    Posts:
    29
    No, they will not. AFAIK, floating-point determinism is not possible in C#, and it is extremely difficult to pull off in C/C++. This article will help explain why: link

    You'll either need to use fixed-point math (slow and limiting) or find a different solution. You might look at Planetary Annihilation's approach to the problem (Chrono Cam tech).
     
    Limyc, Feb 10, 2015
    #3
    Todd-Wasson likes this.