Re: [xmoto-dev] svn 1404 : merged benetnash with trunk

[Janek Polak <benetnash@xxxxxxxxxxxxxx>]

Dnia Tue, 1 May 2007, Nicolas Adenis-Lamarre naskrobal
>  Janek Polak a écrit :
> > Today morning I've invented that this floating point differences can be
> > removed by changeing (replay_time < highscore_time) to (replay_time -
> > highscore_time < -0.01). I'm not perfectly sure if it works, but this
> > solution looks fine. I left comment in case someone invent something
> > better.
>  i found a nice feature of sqlite,
>  it has not a lot of function, however, it allows to add news !

>   sqlite3_result_double(i_context, (double)((int)(v_value)));

It is not working - it truncates 23.0 to 22.0 and so on - from numbers
witout decimal digits it substracts 1. I think that issue may be caused
by some floating point errors. Look at this:

testowe$ cat x.cpp
#include <iostream>
using namespace std;
main()
{

	double x = 23.456;
	printf("%2.20f\n", x);
	printf("%2.20f\n", 100 * x);
}
testowe$ ./x
23.45599999999999951683
2345.59999999999990905053


This 23.456 will be truncated by your function to 2345.5
My nasty workaround is:

sqlite3_result_double(i_context, (double)((int)(v_value + 0.0000001)));

On the other hand we could round number with:

sqlite3_result_double(i_context, floor(v_value + 0.5)));

Anyway I've just commited first workaround and added xm_floor to both
times:

xm_floor(h.finishTime*100.0) > xm_floor(r.finishTime*100.0))