On 9/20/06, Olivier Grant <olivier.grant@gmail.com> wrote:
Right now I have three simple vector classes - ranging from vector2d to vector4d - that are not templetized since I like the idea of being able to access coordinates directly by their name
vector3d vec; vec.x += 10.0f;
Thanks to SFINAE you can do that for the general case, so long as you don't mind vec.x() += 10; Which I don't think is a great hardship. In a math::vector<T,N>, for example, you'd have code like this: boost::enable_if_c< N >= 1, T& > x() { return v[0]; } boost::enable_if_c< N >= 2, T& > y() { return v[1]; } boost::enable_if_c< N >= 3, T& > z() { return v[2]; } boost::enable_if_c< N >= 4, T& > w() { return v[3]; } I've written a fully-templated math::vector class that you can find at http://gpwiki.org/index.php/C_plus_plus:Tutorials:TemplateVector (not using boost though, so it does a bad form of STATIC_ASSERT instead of the enable_if ). That being said, why can't you use uBLAS ( http://boost.org/libs/numeric/ublas/doc/vector.htm ) or some other premade library? Other people have already written heavily-optimized ones, using expression templates and such to keep the nice syntax without adding inefficiencies. (No need for a 3-argument add function, for example.) ~ Scott McMurray