[cad-linux-dev] Re: variably formatted text (now with references:)
- From: "cr88192" <cr88192@xxxxxxxxxxx>
- To: <cad-linux-dev@xxxxxxxxxxxxx>
- Date: Sun, 7 Dec 2003 16:59:52 -0800
----- Original Message -----
From: "Eric Wilhelm" <ewilhelm@xxxxxxxxxxxxx>
To: <cad-linux-dev@xxxxxxxxxxxxx>
Sent: Sunday, December 07, 2003 11:58 AM
Subject: [cad-linux-dev] Re: variably formatted text (now with references:)
> > The following was supposedly scribed by
> > cr88192
> > on Sunday 07 December 2003 01:36 pm:
>
> >not everything will be annonymous, just most things don't need a name...
> >naming is useful for things accessible from elsewhere, or for the sake of
> >users (they may want to name parts of the models).
> >if you say, have a chair, most of the geometry does not need names, but
some
> >groups of geometry (eg: the seat or back) may usefully have names...
> >
>
> I don't see it as a question of whether the names are useful to the user
> or not. It is more a matter of whether they facilitate the
> extensibility of the format.
>
ok.
how much effect this has depends probably on how the geometry is modeled...
> >for parts that are used as functions it may be quite useful to have
names,
> >eg, so one can be like:
> >(office-chair origin: #(0 0 0) height: 2 appolstery: (color #(1 0 0 1))
> >metal: (color #(0.25 0.25 0.1 1)))
>
> If we are just going to render the chair, then the upholstery and metal
> metal would be named for color and texture purposes. But what if we
> want to load-test the chair or calculate the weight of all of the office
> furniture on a floor? Also, to allow the chair design to be easily
> modified, we might wish for the legs to be instances of a "master" leg
> or for the front legs to be mirror images of each other and to know what
> sort of fasteners are used to attach them.
>
the first part seems easier. different properties can be defined for
different models, and the exact semantics of primitives can be opaque. of
course, this may leave things like parts that are unusable for various tasks
(eg: a chair that looks pretty but doesn't have info needed to figure weight
or load capabilities, or a chair that can calculate weight and load but
looks unusably bad...).
the second part seems harder. for the second I am not sure how one would
avoid having to make a new chair...
> Maybe your modeler is not this complicated or someone's drafting program
> is not nearly so complicated. Does this prevent you from using a format
> where everything has a name? If the stored model is accessed through a
> library which implements the names automagically, you would be loading a
> named union which contains some named entities. If you can manage to
> allow just one pointer to tag-along with the entities through all
> operations, the API would pick-up the name out of this pointer in the
> save functions and handle all of the naming for you.
>
ok, cool idea.
I am not sure how needed they are though.
it may just be my limited thinking, I may be thinking too much in
heirarchical/collective terms, or maybe I am just stupid.
> From another approach, maybe one of the "modes" of this library is the
> fully-anonymous mode, where the items are stored with names, but the
> program doesn't even attempt to track them and they are all re-named
> (possibly) on each save operation. This requires some clean-up to
> happen via the library, but still uses a format with everything named
> and linked.
>
ok.
so format is abstracted from language?
or language from format?
I don't think it is possible to abstract both though, or each from itself...
in my case it would be inherently simpler if the language and format are
joined...
I think my motivations are tied to emotions. I had before remembered a
feeling of sadness noticing in games how everything in the world is little
more than imitations (a cube with a texture intended to be a bookshelf),
using no-clipping and leaving the map, only to see how small it was and that
there is no sky, only an empty space filled to a single color or letting the
last image inside the map persist in the form of garbage...
I am not sure why this is, maybe that for me my physical world is not much
more than most games...
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