[geos-devel] Coordinate & Coordinate list (20% faster now)

[Norman Vine]

David Blasby writes:

> I tested my theory:
>
>
> 50,000 points TestSweepLineSpeed
>
> takes about 10.2 seconds on my machine
>
> I changed CoordinateList's getAt(int) from:
>
> Coordinate CoordinateList::getAt(int pos)
> {
>         moveTo(pos);
>         return get();
> }
>
> to:
>
> Coordinate CoordinateList::getAt(int pos)
> {
>     if ((pos>vect->size()-1) || (pos<0) )
>          throw "Invalid argument: out of bounds\n" ;
>     else
>         current=pos;
>     return (*vect)[current];
> }
>
> This is *exactly* the same code, but I pulled the MoveTo() and get() into the function.  This should only really save 2 function
call overheads and one call to the copy constructor.
>
> The results is 8.2 seconds.  Thats 20% faster!!!
>
> So, the CooridinateList is a pretty key code portion!
>
>
> We could probably save a bunch more time by:
>     actually implementing the vector in the class (save a bunch of class calling overhead)
>     returning pointers instead of actual objects
>
>
> I'd love to see the Copy Constructor called only 50,000 times for a 50,000 point input set.
>
> dave
>
>
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