G3Dv4 format spec

[martiño]

ok, so i will fill in a dummy byte in the converter.

Don't do it, I've already uploaded rc7 with packed structures.

[martiño]

but by the way how is it opted on 64bit machines ?

I dont see how 64 machines can be a problem at this point, as all the data-types are fixed-length.

[seltsamuel]

hi martin-o,

it took me a lot time to stumble upon this, but
is it possible that u have corrupt V3 data models ?
with my converter i can load nearly all g3d units into Blender with some exceptions. I first thought i made a mistake somewhere but after fiddeling arount long time i took an hexeditor and inspected the g3d file. the error is inside there. but why the heck can your loader use the model when its not v3 compatible ? the model id says its v3 ????

please look at this and tell me why ?

farm.g3d

i edit in here all models i find with the prob.

EDIT: Whoops seems as i found the Problem  


Seltsamuel

[martiño]

Yes, if a mesh has no texture then, as far as I remember, no texture coordinates are stored and you need to handle this special case.

[seltsamuel]

I have a little feature request martin-o,

in my researches for the Blender Script i read many threads now,
is it possible to support quadruples too not only triangles in the models ?
I think it will be not to hard to change it, but will increasy the Quality of the Models extreme (Opinion of the most designers i dont know it because im not one of them  :roll: ).
The decision of is it a triangle or a quad is the 4. vertexcoordinate is it empty then its a triangle else its a quad.

Blender supports native Modelling in Quads, for the Exporter its not too hard to convert the Quads into 2 triangles but why not support quads when u get better Quality too ? in most cases u even need lesser Faces.

The only negative is that u need 4 coordinates for the Faces that may expand the Filesize a little, but it will show if its not really expanding because u need lesser Faces. Does 3D Studio even support Quads ?

Need your Opinion on this and maybe the Opinion of some Artists working
actively to Model things.

Seltsamuel

[Speedator]

Yes, 3ds max supports this like almost every 3d-modeller. And you really get much better results with it. I personally use  models with quads everytime i am able. If you use quads in the right way(building only almost flat plane-quads) the models often look much better. I do not know if it looks less good converting quads in triangles at the end. Also I do not know why it should change anything to do so, except you have a smooth-algorithm for the models. For the design itself, quad-modelling is very useful to get better reesluts.

Hope you understand what I mean.

[seltsamuel]

Im the same opinion thats why i do this feature request,

but because i have at time no knowledge of the 3D Engine inside Glest
martin-o should decide if its only little or to much work to support quads.

In my Opinion support for Quads is a Feature that a Modern Engine should have, because quads are not added to the modeller software without a reason (ancient times they only know Triangles).
There are features like different (Named)  animation Trees inside the Model, Skeletal animation with Bones .. .. .. and some other things i would appreciate to have em too, but i know that there is some work to do that, so maybe it will come later (maybe i try to offer a little time to it but laaaater). The Export Script already consumes way to much of my Time.

Seltsamuel

[Speedator]

I said quads itself do not change anything. It is easier to design with it.
But if the smoothing of the model depends on the different between and triangle, then it might change the result.

edit: And this dependency may be a little bit more complex to implement.

[Speedator]

Okay, I tried out, it changes a little bit, but the main factor is the easier way to design using quads. But we should hear different opinions. Maybe I am at fault. I must test more to say more about.

[seltsamuel]

The problem i see is when u use quads in modelling and as i heard its a good thing then u will when exporting double the faces with one hit 1 quad = 2 triangles think thats not good for the performance of the engine. the other point is to point out where to cut the quad into triangles (u can not say a quad is a cube it might look way different)  i found some nice algorithm to do that but will slow down export because i must calculate every triangle (that includes recalculation of  normals and uvmapping). This is the reason i ask to maybe implement quads in the Engine. When its good to model things why not use it in the engine ? (if its not much work but the decision is on martin-o).

Seltsamuel

[martiño]

In my opinion, It's a bit pointless to add Quad support since every quad can be converted into 2 triangles, and the cost of rendering 2 triangles is the same as rendering two quads (same number of vertices, same number of pixels).

Quads have also a problem: all vertices must be in the same plane, so its in fact possible to add inconsistent quads to a scene, triangles are always correct, since 3 points always define a plane.

I don´t know if 3dsmax lets you make meshes of quads, but in the maxsdk all the programmer can see is a bunch of triangles.

Martin-o.

[seltsamuel]

Hi,
The question is not if it costs more to render 2 triangles or 2 quads.
The Point is if it costs more to render 2 quads or 4 triangles because the
FACES double. The Vertices may be the same but the faces will increase.
I have no problem to convert into triangles but the question was what is better for the Future ? quads are not integrated into the modellers without a reason. Im no Artist so i can only tell what many people on different Boards say and that is that the models look nicer with quads and many features in the modelling software (for example UV Mapping) is much more efficient with quads than with triangles. So i thing during modelling the Artists will make heavy use of quads (most time without thinking that an export will double the faces).
If you say u see no necessary term to integrate quads into the engine it is so and i will convert to triangles. if its not so much work (and i think its not so much but i dont know the engine) so why not implement it ? Most other engines support it.

I not understood what u told about the Problem with Quads with planes ? can u explain it ?

Seltsamuel

[MatzeB]

I don't think that many 3d engines support quads. After all if they don't add additional benefits (or nearly none) you better keep the code clean and simple.

[seltsamuel]

Now i found the Informations i was missing to understand it.

I found a nice Article where this Tri and Quad Thing is explained, there its stated that because the Hardware of the GraficBoards is optimized and layed
out for Triangles the Engine has to cut em into Triangles when not done before. When the Hardware would not be on Triangles Quads would be the sucessor on the Market. Is this Right ?

I not knowed this because i already told im no 3D Expert and am here to learn something. If this is the right Explanation there is no further  Discussion necessary.

Seltsamuel