6
votes
Is it possible to create minimal glTF files with vertex and index buffers?
While creating a set of glTF models for a tutorial, I also intended to create THE minimal glTF file.
Update: The following referred to glTF 1.0/1.1. See below for an update of this example to glTF 2....
- 218
5
votes
Accepted
What's the simplest, open, animation format?
For what it's worth, the glTF Tutorials contain a section on Skinning that shows how the raw vertex and joint weight data feed into a vertex shader to distort the mesh.
If you do design your own ...
- 369
4
votes
Is it possible to store the plain buffer data in gltf files?
Embedding human readable data is not supported. However you can put the data into a data uri to store the data inline in base64 format.
...
- 5,920
4
votes
Is it possible to create minimal glTF files with vertex and index buffers?
You can put the data into a data uri to store the data inline in base64 format.
...
- 5,920
3
votes
Accepted
Is it possible to create minimal glTF files with vertex and index buffers?
After spending a hard time to understand the way how the binary buffers work in the gltf files I finally managed to generate a truely minimal gltf file. It's a single yellow triangle (demo).
I tried ...
- 703
3
votes
Accepted
glTF animation keyframe question
You're seeing channels and samplers there, not individual keyframes. In this case, one animation is simultaneously targeting the translation, rotation, and scale channels of the same node, with three ...
- 369
3
votes
Accepted
How mesh geometry data (vertex coordinates) stored in glTF?
The min and max values provide an outer bounding box for all POSITION data within a given ...
- 369
2
votes
How to encode/decode buffer data in glTF?
In addition to @russ' answer, I was able to decode the buffer with the gltf Utilities.
...
- 703
2
votes
Accepted
How to encode/decode buffer data in glTF?
The information you're looking for is defined in the 'accessors' and 'bufferViews' near the top of the source file you linked.
Bufferviews simply divide the buffer up into sub ranges and define ...
- 2,372
2
votes
Accepted
How to generate binary gltf array buffers?
I've finally managed to write the buffers myself using JavaScript.
The result is a base64 encoded String, like:
...
- 703
2
votes
How to generate binary gltf array buffers?
Technically any file format where you can dump the entire file into a VBO and then render from that will work for the .bin files. Unfortunately those formats are less well known than they should be.
...
- 5,920
2
votes
Accepted
Is it possible to store the plain buffer data in gltf files?
It's not possible to store the plain text array buffers in gltf, however, here is the code I use to generate buffers in JavaScript:
...
- 703
2
votes
Determining the Bounding Box values of a glTF file
There isn't a bounding box for the whole glTF file, but individual primitives have POSITION accessors that indicate min and <...
- 369
2
votes
Programmatically generating bin files for GLTF models
Building upon the answer by @shashankan and another answer in Blender, I wrote a Blender script to convert from FBX into a subfolder with GLTFs.
(You may want to remove my scaling code, which scales ...
2
votes
Programmatically generating bin files for GLTF models
The .bin file that goes with a .gltf only includes mesh data (position, normal, uv, other vertex attributes as needed). It does ...
- 369
2
votes
When and who introduced the idea of a scene graph?
Not 3D as such, but it seems in 1963 Ivan Sutherland's seminal "Sketchpad" (and wikipedia) had instancing. eg. See "Chapter VI RECURSIVE FUNCTIONS" of the 2nd reference.
IIRC ...
- 4,181
2
votes
Inspecting gltf animation data
I help maintain an open-source extension for VSCode called glTF Tools.
Find the sampler for your animation. The input values will point to a list of times, and <...
- 369
1
vote
Accepted
Uploading interleaved data in gltf buffers
It is slightly better to combine buffers since it reduces the amount of state that OpenGL has to track, which reduces memory usage overall, and helps reduce state changes.
But you only really get ...
- 3,030
1
vote
How to properly use the BRDF from glTF 2.0 specification in path tracing while using metallic/roughness materials?
In rendering, we want to integrate over the light paths (with Monte Carlo integration). The common simplification is that the emissive surfaces emit radiance and the camera is sensitive to radiance, ...
- 1,950
1
vote
How does one construct a 3D file format from pixels and vertices?
Here is an overview of how you would go about producing an glTF asset from your data.
First, write your index and vertex data arrays into files.
They can be all the same file, but for the ...
- 1,016
1
vote
How does one construct a 3D file format from pixels and vertices?
The list of pixels would typically be encoded as one of the popular image formats like ktx if it is going to be consumed by other rendering programs, or jpg if it is just for viewing. The vertices, ...
- 3,030
1
vote
How to apply transformation matrices from multiple primitives on a mesh
In the glTF format, "primitives" are just a way to specify separate draw calls (and hence, separate materials or shader programs) for a single mesh. There is no transform, as you've ...
- 369
1
vote
How to apply a linear transformation to gltf data
When transforming normal vectors we have to be careful to check that the transform itself is equal to its own inverse transpose. Or just do an inverse transpose on the matrix. This is usually the case,...
- 3,030
1
vote
Accepted
Why are these 2 buffers joint while extracting glTF information?
The accessor (model.accessors[accessor_index]) has its own byteOffset and count values that ...
- 369
1
vote
Convert a .X mesh to a modern format
Perhaps Assimp will work for you? In particular, it has a command line tool for converting between formats.
- 237
1
vote
Convert a .X mesh to a modern format
Blender appears to have a .X importer. It's a plugin that ships with Blender, but is disabled by default, so you have to enable it in User Preferences. See: https://blender.stackexchange.com/a/8749/...
- 369
1
vote
Accepted
Programmatically generating bin files for GLTF models
To anyone who is reading this in future:
I ended up taking an alternative route: Blender scripting.
Blender comes with a built-in GLTF / GLB exporter. Here is what the render pipeline looks like in ...
- 151
Only top scored, non community-wiki answers of a minimum length are eligible