public static int logmath_add(Pointer <logmath_t> lmath, int logb_x, int logb_y)
{
logadd_t t = lmath.Deref.t;
int d, r;
/* handle 0 + x = x case. */
if (logb_x <= lmath.Deref.zero)
{
return(logb_y);
}
if (logb_y <= lmath.Deref.zero)
{
return(logb_x);
}
if (t.table_uint8.IsNull)
{
return(logmath_add_exact(lmath, logb_x, logb_y));
}
/* d must be positive, obviously. */
if (logb_x > logb_y)
{
d = (logb_x - logb_y);
r = logb_x;
}
else
{
d = (logb_y - logb_x);
r = logb_y;
}
if (d < 0)
{
/* Some kind of overflow has occurred, fail gracefully. */
return(r);
}
if ((uint)d >= t.table_size)
{
/* If this happens, it's not actually an error, because the
* last entry in the logadd table is guaranteed to be zero.
* Therefore we just return the larger of the two values. */
return(r);
}
switch (t.width)
{
case 1:
return(r + ((t.table_uint8)[d]));
case 2:
return(r + ((t.table_ushort)[d]));
case 4:
return(checked ((int)(r + ((t.table_uint32)[d]))));
}
return(r);
}
public static int fast_logmath_add(Pointer <logmath_t> lmath, int mlx, int mly)
{
logadd_t t = lmath.Deref.t;
int d, r;
/* d must be positive, obviously. */
if (mlx > mly)
{
d = (mlx - mly);
r = mly;
}
else
{
d = (mly - mlx);
r = mlx;
}
return(r - ((t.table_uint8)[d]));
}
public logmath_t()
{
t = new logadd_t();
}
