public LSL_List llList2ListStrided(LSL_List src, int start, int end, int stride)
{
LSL_List result = new LSL_List();
int[] si = new int[2];
int[] ei = new int[2];
bool twopass = false;
if (!ScriptProtection.CheckThreatLevel(ThreatLevel.None, "LSL", m_host, "LSL", m_itemID)) return new LSL_List();
// First step is always to deal with negative indices
if (start < 0)
start = src.Length + start;
if (end < 0)
end = src.Length + end;
// Out of bounds indices are OK, just trim them
// accordingly
if (start > src.Length)
start = src.Length;
if (end > src.Length)
end = src.Length;
if (stride == 0)
stride = 1;
// There may be one or two ranges to be considered
if (start != end)
{
if (start <= end)
{
si[0] = start;
ei[0] = end;
}
else
{
si[1] = start;
ei[1] = src.Length;
si[0] = 0;
ei[0] = end;
twopass = true;
}
// The scan always starts from the beginning of the
// source list, but members are only selected if they
// fall within the specified sub-range. The specified
// range values are inclusive.
// A negative stride reverses the direction of the
// scan producing an inverted list as a result.
if (stride > 0)
{
for (int i = 0; i < src.Length; i += stride)
{
if (i <= ei[0] && i >= si[0])
result.Add(src.Data[i]);
if (twopass && i >= si[1] && i <= ei[1])
result.Add(src.Data[i]);
}
}
else if (stride < 0)
{
for (int i = src.Length - 1; i >= 0; i += stride)
{
if (i <= ei[0] && i >= si[0])
result.Add(src.Data[i]);
if (twopass && i >= si[1] && i <= ei[1])
result.Add(src.Data[i]);
}
}
}
else
{
if (start % stride == 0)
{
result.Add(src.Data[start]);
}
}
return result;
}
