"Olivier Grant" <olivier.grant@gmail.com> wrote:
Hi,
I have written a bit of code to handle geometric vectors in a generic way, abstracting their dimension. The idea behind this code is to be able to apply one operation between two vectors, or a vector and a scalar, whatever their dimension, and writing it in an expandable way without having to modify any manipulation functions if a new geometric vector class is created. The other advantage is that the resulting assembly code is just as fast as if the functions had all been explicitly written.
Does this hold true if the equations get complicated (e.g. products of products)?
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;
to give you an example of the syntax, here is how you would add two vectors of different dimensions :
vector2d v1(1.0f, 2.0f); vector3d v2(-1.0f, 3.0f, 2.0f); vector4d res;
vector_add(v1, v2, res); /* res now contains (0.0f, 5.0f, 2.0f, 1.0f) */
This is a bit clunky. What about using the operator+() and operator=()?
the result is determined by the dimension of the third vector passed to vector_add. v1 is auto-promoted to act like a vector3d.
This seems wrong. If I want to add a vector2d to a vector3d, then I should have to do it manually. Otherwise, it should be a type error.
v2 does not change. res gets (v1.x + v2.x, v1.y + v2.y, v1.z + v2.z, default_w_value).
I didn't seem to find any information on a lib currently under development that provides geometric vector manipulation in that way - maybe apart from uBLAS - so I thought I would share this if anyone seems to be interested.
What are the advantages of this library over tvmet[1]? Cheers, Walter Landry wlandry@ucsd.edu [1] http://tvmet.sourceforge.net/