On Fri, Mar 27, 2009 at 12:23 PM, Phil Endecott <spam_from_boost_dev@chezphil.org> wrote:
Kornel Kisielewicz <kornel.kisielewicz@gmail.com> wrote:
One example is object hierarchy via oct or kd trees.
Would you like to implement these spatial containers? I think this would be a very useful contribution. Ideally your implementation would be generic, i.e. usable with fixed-size point types or the variable-size uBLAS types; at the end of the project we would then be able to evaluate the benefit of removing the size field. 2D & 3D please.
This is exactly my intention.
- Although I doubt that wasting a word on a size field has much effect on speed, I would want to avoid it when dealing with large collections of points because of the memory overhead.
I'm not too much worried about the memory, as I am about data alignment. Also, in the case of 4d vectors, you'd have 5 values, which doesn't scale well ( 4*32 bits = 128bits which is nice -- an addition would ruin this niceness ).
- I have using uBLAS for some simple 2D matrix transformation and found it a little bit more difficult than I expected; a special-purpose API, even if implemented as a thin wrapper around uBLAS or something else, would have the benefit of simplifying things for the end user.
Fully agreed. -- regards, Kornel Kisielewicz