[Haskell-cafe] How to model outer space for a MUD

[Tikhon Jelvis]

The problem with just modeling things is that certain questions become
difficult. For example, it's often useful to know what thing is closest to
some given thing, or what a thing's closest neighbor is.

Moreover, while there is certainly a lot of space out there, this is
Haskell so we can model all of it lazily. That's what Conal's blog post is
about: a practical way to lazily model images with no bounds and no
resolution limit.
On Aug 14, 2015 3:31 PM, "Jeffrey Brown" <jeffbrown.the at gmail.com> wrote:

> I would not model space -- there's too much of it -- rather Things in
> space. Each Thing has a 3d coordinate (plus more geometric information,
> plus more information). Things can be rooms, and things can have position
> defined in terms of other things.
>
> On Fri, Aug 14, 2015 at 3:23 PM, Michael Litchard <michael at schmong.org>
> wrote:
>
>> Well, thinking more about it, I think I want an 8-regular complete graph.
>> I've been doodling and came to the conclusion pretty quickly that thinking
>> of this space in terms of a grid wasn't quite right. I *would* like to only
>> hold data of populated nodes if possible, to model an infinite space as
>> David mentioned. I've been looking at fgl to help me think about this
>> problem in terms of a graph. I'll think and tinker over the weekend and see
>> if I can come up with something more articulate. Not committed to a graph,
>> but I want a discrete structure and this looks like it fits the bill at the
>> moment.
>>
>> On Fri, Aug 14, 2015 at 2:00 PM, KC <kc1956 at gmail.com> wrote:
>>
>>> I agree with Tikhon
>>>
>>> But a sparse matrix might be conceptually simpler to start with
>>> But are sparse matrices easy to implement in Haskell and then is it easy
>>> to change the data structure layer on?
>>>
>>> --
>>> --
>>>
>>> Sent from an expensive device which will be obsolete in a few months! :D
>>>
>>> Casey
>>>
>>> On Aug 14, 2015 1:50 PM, "Tikhon Jelvis" <tikhon at jelv.is> wrote:
>>>
>>>> It depends on exactly what you want to represent and how you want to do
>>>> it.
>>>>
>>>> The first thing that comes to mind for me would be using an octtree[1],
>>>> which is the three-dimensional analog of a quadtree[2]. Conal Elliott has
>>>> an interesting point about using quadtrees to represent images in
>>>> Haskell[3], and you should be able to adapt the idea to indexing into a
>>>> three dimensional world with an octtree.
>>>>
>>>> [1]: https://en.wikipedia.org/wiki/Octree
>>>>
>>>> [2]: https://en.wikipedia.org/wiki/Quadtree
>>>>
>>>> [3]: http://conal.net/blog/posts/topless-data
>>>>
>>>> On Fri, Aug 14, 2015 at 1:44 PM, David McBride <toad3k at gmail.com>
>>>> wrote:
>>>>
>>>>> If you are thinking of it as a 3d grid, you might just have a (Map
>>>>> (Integer, Integer, Integer) Contents, where every room in this 3d grid that
>>>>> has something in it is in the map and every room that is empty space has no
>>>>> corresponding entry in the map.
>>>>>
>>>>> Then when you enter a room you can quickly look up what is in that
>>>>> room, then reasonably quickly check the neighbors in every direction to see
>>>>> what the ship might be able to sense were it to travel in that direction.
>>>>>
>>>>> In this case, space is infinite, but the datastructure is only as big
>>>>> as the amount of content you have.
>>>>>
>>>>> On Fri, Aug 14, 2015 at 4:34 PM, Michael Litchard <michael at schmong.org
>>>>> > wrote:
>>>>>
>>>>>> Star Wars MUD has a 3-D coordinate system such that (0,0,0) is some
>>>>>> planet. I'm curious as to how one might model this system that could
>>>>>> simulate a ship's movement through a 3-D grid. Matrix, 3-D array, graph.
>>>>>> None of these? Ideas?
>>>>>>
>>>>>> _______________________________________________
>>>>>> Haskell-Cafe mailing list
>>>>>> Haskell-Cafe at haskell.org
>>>>>> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
>>>>>>
>>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> Haskell-Cafe mailing list
>>>>> Haskell-Cafe at haskell.org
>>>>> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
>>>>>
>>>>>
>>>>
>>>> _______________________________________________
>>>> Haskell-Cafe mailing list
>>>> Haskell-Cafe at haskell.org
>>>> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
>>>>
>>>>
>>> _______________________________________________
>>> Haskell-Cafe mailing list
>>> Haskell-Cafe at haskell.org
>>> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
>>>
>>>
>>
>> _______________________________________________
>> Haskell-Cafe mailing list
>> Haskell-Cafe at haskell.org
>> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
>>
>>
>
> _______________________________________________
> Haskell-Cafe mailing list
> Haskell-Cafe at haskell.org
> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.haskell.org/pipermail/haskell-cafe/attachments/20150814/0f8d7671/attachment.html>