Re: [Gnu3dkit-dev] 3D file formats

[Philippe C . D . Robert]

Hi,

On Sunday, September 29, 2002, at 08:13 PM, Matt Brandt wrote:
> I guess I would lean toward something halfway between a bunch of 
> reader/writer classes and a database. It seems to me like the scene 
> graph really is the database, but we might need to add a little bit of 
> information to make things more explicit. Named nodes would be the main 
> thing I can think of, so that a scene object could be reused without a 
> great deal of work. If we try to get into the idea of merging nodes I 
> think we can end up breaking things inadvertently. In some scenes an 
> object might seem like a static object most of the time and just need 
> to be dynamic for one thing. Only the creator will know for sure. 
> Optimizations like that can be left up to the program that creates the 
> scene (or the person).

I agree that a database should mainly be used to serve as a clean 
import/export interface. But I can imagine some sort of optimisations 
which can be done on that level, ie. when optimising for a specific 
target rendering device.

What do you mean by 'named nodes'? You already can name G3DGraphNodes, 
can't you?

> I lean toward doing a protocol for a reader/writer and then 
> implementing the file formats separately without an intermediate format.

My first design proposal is more influenced by the NSImageRep class 
cluster, thus every concrete reader/writer is a subclass of the 
G3DDatabase but has to implement only the scene format specific code.

-Phil
--
Philippe C.D. Robert
http://www.nice.ch/~phip