Re: [glob2-devel] Bug in Map.cpp Checksum computation

[Nuage]

Thank you! Yes, this is an error, all checkSum() methods has to use
Uint32! There where identical mistakes in:
Map.cpp
MultiplayersHost.cpp
MultiplayersJoin.cpp
It is fixed in cvs.

simon schuler wrote:
> The checksum computation here is almost useless: It returned the same 
> value for over a minute, until i quit the game...
>
>    Sint32 Map::checkSum(bool heavy)
>    {
>        Sint32 cs=size;
>        if (heavy)
>            for (int y=0; y<h; y++)
>                for (int x=0; x<w; x++)
>                {
>                    ...
>                    cs=(cs<<1)|(cs>>31);
>                }
>        return cs;
>    }
>
> The rotate Statement cs=(cs<<1)|(cs>>31); is wrong for signed integers 
> and will overwrite the whole integer with 0xFFFFFFFF when cs is negative.
> Game.cpp expects an Uint32 as return type anyway, so we just have to 
> change the type of cs to Uint32,  and make Map::checkSum return an 
> Uint32. After changing this, it returned usable values...
>
> Simon
>
>
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