 | | Re: A comprehensive LDraw object model
|
|
How about an LDraw DAT model reducer - something that hacks out the insides and leaves nothing but a hollow shell? This way you could port it to platforms that can't handle so many polygons, and also render in realtime. It would kind of be like (...) (23 years ago, 10-Feb-02, to lugnet.cad.dev)
|
| |
| | Re: A comprehensive LDraw object model
|
|
(...) Actually this brings up a different issue. I haven't put alot of thought into it yet, but I think it would be useful to add information in the part files that would allow a program to differentiate between geometry that represents 'outside' (...) (23 years ago, 10-Feb-02, to lugnet.cad.dev)
|
| |
| | Re: A comprehensive LDraw object model
|
|
(...) IIRC (and I wish I could find the reference) the LDraw spec does support this. It depends on the order of the points in the polygon; e.g. clockwise points out, counterclockwise points in. Or something like that. But last I heard of this, there (...) (23 years ago, 10-Feb-02, to lugnet.cad.dev)
|
| |
| | Re: A comprehensive LDraw object model
|
|
(...) Backface culling (BFC) is what you are describing, but it isn't what Kyle was asking for :-). In traditional realtime 3D rendering, polygons only have one side. The back side is literally non-existent. It doesn't get drawn at all. This is (...) (23 years ago, 10-Feb-02, to lugnet.cad.dev)
|
| |
| | Re: A comprehensive LDraw object model
|
|
(...) Yes, What you're describing does sound like BFC to me. As someone else (travis I think?) said, BFC is a useful optimiziation for reducing the number of surfaces that need to be drawn. But it's not the same thing I was talking about. BFC (...) (23 years ago, 11-Feb-02, to lugnet.cad.dev)
|
| |
| | Re: A comprehensive LDraw object model
|
|
(...) A couple of different approaches to this have been discussed before. I think the most generic solution was to implement a 0 DETAIL <level> meta-command, that would identify the detail-level of the following lines. A 0 detail level indicates (...) (23 years ago, 11-Feb-02, to lugnet.cad.dev)
|
| |
| | Re: A comprehensive LDraw object model
|
|
(...) Could you give us an example? By looking at what you've written, I don't understand if one needs an ending tag, or not, to complete the '0 DETAIL' command. Where in the text of the file would this go? How would it look? Thanks a lot. Much (...) (23 years ago, 11-Feb-02, to lugnet.cad.dev)
|
| |
| | Re: A comprehensive LDraw object model
|
|
"Kyle McDonald" <kmcdonald@bigfoot.com> skrev i meddelandet news:3C671582.801040...oot.com... (...) If the parts are BFC compliant, there's no need to tag for 'top', 'left' etc. as this information is already there in the surface normal (with much (...) (23 years ago, 11-Feb-02, to lugnet.cad.dev)
|
| |
| | Re: A comprehensive LDraw object model
|
|
(...) Well again BFC is only useful for culling surfaces that face away from you. It doesn't really do anything for faces that face you but are blocked by other faces. When I talked about top, left, right, etc, I was envisioning some system by which (...) (23 years ago, 11-Feb-02, to lugnet.cad.dev)
|
