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Audio has mp3. Video has H.264. Images have png and jpg. What does 3D content have? Wavefront .obj?

by Keyframe 12y ago

elisee 12y ago
Yup, but it only supports static geometry. Looks like glTF has animation support.
- Keyframe 12y ago
  In "offline" world all we ever use is objs and alembic as of recently. I wonder if alembic is suitable for realtime use.
hesdeadjim 12y ago
.obj is a horrid format for runtime usage in a game engine. The effort required to parse a non-trivial model will explode your load times on resource constrained systems. The content pipeline that I implemented for our game engine always converted .obj files into a binary format that is trivial to load at runtime. In an ideal world (i.e. not Android), your binary format is one that you can simply mmap into your process and then at worst "loading" consists of copying this memory and doing some pointer fixups.
- meelooo 12y ago
  Yes, and that's why one can wonder why they once again chose JSON for part of this new "web standard". Text based data formats should die.
wolfgke 12y ago
According to the text a glTF asset is represented by: * JSON file (.json) containing the node hierarchy, materials, and cameras * Binary files (.bin) containing geometry and animations * Image files (.jpg, .png, etc.) for textures * GLSL text files (.glsl) for GLSL source code for individual stages See also https://github.com/KhronosGroup/glTF/tree/master/model/duck https://github.com/KhronosGroup/glTF/tree/master/model/duck for an example.
jjoonathan 12y ago
From TFA: > There are industry-standard interchange formats, namely COLLADA, that allow sharing assets between modeling tools and within the content pipeline in general. However, these formats are not optimized for size or runtime use and neither are modeling-tool-specific formats. At runtime, an application wishing to render an asset needs to do a significant amount of processing to transform the asset's content into data appropriate for the GL APIs.

Audio has mp3. Video has H.264. Images have png and jpg. What does 3D content have? Wavefront .obj?

elisee 12y ago

Yup, but it only supports static geometry. Looks like glTF has animation support.

Keyframe 12y ago
In "offline" world all we ever use is objs and alembic as of recently. I wonder if alembic is suitable for realtime use.

hesdeadjim 12y ago

.obj is a horrid format for runtime usage in a game engine. The effort required to parse a non-trivial model will explode your load times on resource constrained systems. The content pipeline that I implemented for our game engine always converted .obj files into a binary format that is trivial to load at runtime. In an ideal world (i.e. not Android), your binary format is one that you can simply mmap into your process and then at worst "loading" consists of copying this memory and doing some pointer fixups.

meelooo 12y ago
Yes, and that's why one can wonder why they once again chose JSON for part of this new "web standard". Text based data formats should die.

wolfgke 12y ago

According to the text a glTF asset is represented by: * JSON file (.json) containing the node hierarchy, materials, and cameras * Binary files (.bin) containing geometry and animations * Image files (.jpg, .png, etc.) for textures * GLSL text files (.glsl) for GLSL source code for individual stages See also https://github.com/KhronosGroup/glTF/tree/master/model/duck https://github.com/KhronosGroup/glTF/tree/master/model/duck for an example.

jjoonathan 12y ago

From TFA: > There are industry-standard interchange formats, namely COLLADA, that allow sharing assets between modeling tools and within the content pipeline in general. However, these formats are not optimized for size or runtime use and neither are modeling-tool-specific formats. At runtime, an application wishing to render an asset needs to do a significant amount of processing to transform the asset's content into data appropriate for the GL APIs.