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OpenGL Using the .X model format

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wall    134
I've been programming using the OpenGl API for a few years now but recently decided to learn Direct3D aswell. In the experiment project I'm working on now I will use the .X model format to draw meshes. Are there any drawbacks on using that format opposed to rolling my own format or using some other standard format(.obj, .3ds etc..)? I thought it was a very convenient way to draw meshes since you get all these helping functions in the D3DX library, and it was developed to especially suit game development (right?). But I don't think I've seen any commercialy released game that uses this format, only demos and tutorials I've found on the net, that's why I'm asking. I don't really know anything about the file format, so excuse me if I'm asking sbout something obvious.

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Armadon    1091
Hi there wall,
How are you doing?

The Problem
Using .x files

The Solution
They are awesome and you should think of using them for as long as you can until you run into it's limits and the moving onto your own file formats or using other file formats such as quake/doom BSP's and such or exporting your own from 3d modelling packages. You should use them if they suite your needs and as far as the helpful functions that come with the SDK go, they are awesome aren't they? :). The reason you might run into snags are the added goodies that you have with other formats or creating your own is the fact that that you can add if you desire shaders, lights, etc.. and then export them using your own exporter from a package like 3dstudio max.

I really love using them and they suite my needs for almost everything. Obviously everything has it's limits.

I hope this helps,
Welcome to the world of DirectX :) We hope you enjoy your stay.

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rip-off    10979
i made a program a while ago that loaded the "old style" direct x meshes into opengl.

iut was my first and only attempt at three D, never got around to loading animation data.

but the point is that with the .x file( and other ) format you can load in the meshes and texture data, etc and then arrange them in memory anyway you like

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wall    134
Thanks for the response, both of you!

Quote:
Original post by Armadon
The reason you might run into snags are the added goodies that you have with other formats or creating your own is the fact that that you can add if you desire shaders, lights, etc.. and then export them using your own exporter from a package like 3dstudio max.


Ok, so I can't get shaders embedded in the model file..But if I want shaders it works just fine to use external CG/HLSL shaders when rendering the model, right? Isn't that the best way to do things even if I can get shaders into the file? To save space when models share shaders and to speed up rendering by sorting by shader. Thoughts?

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neneboricua19    634
Quote:
Original post by wall
Ok, so I can't get shaders embedded in the model file..But if I want shaders it works just fine to use external CG/HLSL shaders when rendering the model, right? Isn't that the best way to do things even if I can get shaders into the file? To save space when models share shaders and to speed up rendering by sorting by shader. Thoughts?

Well, the model itself doesn't have to store the shader. It just needs to specify which shader to use. Your engine would see that it uses some particular shader and would then load it up. If a second model uses that same shader, your engine *should* see that this shader has already been loaded and would not try to load it again.

neneboricua

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