[geos-devel] re:GEOS

[Artem Pavlenko]

Hi strk,

Thanks for your reply.

>Thank you for your interest, GEOS needs some storming at the moment. 
>About boost, I'd prefer to keep things simple and requirements low.
>  
>
OK, here is some storming:-)
I suggest the following:

1. DONT do any optimization before datastructures, memory allocation etc 
are sorted!!!
It might just obfuscate the algorithms and not lead to any performance 
gains.

But instead:
2. Go through all the source and make sure that copying semantics are 
implemented as they should be,
e.g something in Java:

Geometry(type1 a,type2 b) {
    a_=a;
    b_=b;  
}

doesn't translates into:

Geometry(const type1& a,const type2& b) {
    a_=a;
    b_=b;  
}

In C++ it is wrong and inefficient.

3. Where is operator=(const Object&) ?
Well, the compiler would generate one for you, but it's not a good idea 
to rely on it.

4. Don't implement copy constructor in terms of assigment operator 
(especially using a compiler generated one) e.g:
 
Object (const Object& other)
{
    a_=other.a_;  
    b_=other.b_;
}  

is wrong.
I bet most of the performance bottleneck will be solved by just applying 
the above.

Re:boost
If you don't want GEOS to have extra dependencies, that's fine.
Why don't you use 
http://svn.berlios.de/viewcvs/mapnik/trunk/src/ptr.hh?rev=17&view=markup 
for your smart pointer needs? I does work for me. Or find something 
else, there's plenty of other stuff around.
 

>Proposal for template application are welcome. 
>
Well, one obvious thing would be to have PrecisionModel as a template 
parameter:

template<typename PrecisionModel>
struct geometry
{
///  
};
typedef geometry<MyPrecisionModel> MyGeometry;

I can come up with something more concrete if you like, but I need to 
have a look at the implementation details.
Do you agree with the above?

Cheers!
Artem