// Dick Hollenbeck's KiROUND R&D
// This provides better project control over rounding to int from double
// than wxRound() did. This scheme provides better logging in Debug builds
// and it provides for compile time calculation of constants.
#include <stdio.h>
#include <assert.h>
#include <limits.h>
//-----<KiROUND KIT>------------------------------------------------------------
/**
* KiROUND
* rounds a floating point number to an int using
* "round halfway cases away from zero".
* In Debug build an assert fires if will not fit into an int.
*/
#if defined( DEBUG )
// DEBUG: a macro to capture line and file, then calls this inline
static inline int KiRound( double v, int line, const char* filename )
{
v = v < 0 ? v - 0.5 : v + 0.5;
if( v > INT_MAX + 0.5 )
{
printf( "%s: in file %s on line %d, val: %.16g too ' > 0 ' for int\n", __FUNCTION__, filename, line, v );
}
else if( v < INT_MIN - 0.5 )
{
printf( "%s: in file %s on line %d, val: %.16g too ' < 0 ' for int\n", __FUNCTION__, filename, line, v );
}
return int( v );
}
#define KiROUND( v ) KiRound( v, __LINE__, __FILE__ )
#else
// RELEASE: a macro so compile can pre-compute constants.
#define KiROUND( v ) int( (v) < 0 ? (v) - 0.5 : (v) + 0.5 )
#endif
//-----</KiROUND KIT>-----------------------------------------------------------
// Only a macro is compile time calculated, an inline function causes a static constructor
// in a situation like this.
// Therefore the Release build is best done with a MACRO not an inline function.
int Computed = KiROUND( 14.3 * 8 );
int main( int argc, char** argv )
{
for( double d = double(INT_MAX)-1; d < double(INT_MAX)+8; d += 2.0 )
{
int i = KiROUND( d );
printf( "t: %d %.16g\n", i, d );
}
return 0;
}
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