Questions tagged [gltf]

The GL Transmission Format (glTF) is a runtime asset delivery format for GL APIs: WebGL, OpenGL ES, and OpenGL. glTF bridges the gap between 3D content creation tools and modern GL applications by providing an efficient, extensible, interoperable format for the transmission and loading of 3D content.

The GL Transmission Format (glTF) is a runtime asset delivery format for GL APIs: , , and . glTF bridges the gap between 3D content creation tools and modern GL applications by providing an efficient, extensible, interoperable format for the transmission and loading of 3D content.

The need for a network-enabled 3D content delivery format such as glTF has been compared to the need for JPEG for images, and MP3 for audio.

Specification

The glTF specification is maintained by the Khronos Group. This standards organization is also responsible for OpenGL, WebGL, COLLADA, and others.

Sample Models

A collection of Sample models are available for learning glTF, and testing runtime engines and content pipeline tools.

Converters and Exporters

glTF files can be created by converting from other popular formats such as , OBJ, , and others. View the list of converters.

As support for glTF grows, 3D authoring packages may gain the ability to export to glTF directly. For example, a exporter is in early stages of development.

Loaders and Viewers

Support for glTF is available for , , , , and others. Khronos maintains a list of glTF loaders and viewers.

File Structure

A structural overview diagram (by Marco Hutter) shows an at-a-glance view of the structure of a glTF file and its contents.

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Is it possible to store the plain buffer data in gltf files?

The GL Transmission Format comes along with a JSON styled main file which basicly describes the scene and binary files which contain the buffers. I'm currently writing a WebGL library and I need to work alot with the vertex and index buffers. So,…
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Is it possible to create minimal glTF files with vertex and index buffers?

I am currently looking into glTF to use as a transfer format for my WebGL project. I already have the geometries I wish to render on my WebGL client available as preprocessed vertex and index buffers (and color buffers, but let's ignore them for…
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Determining the Bounding Box values of a glTF file

Is there a way when looking at the source of a glTF file that you can determine what the boundingBox values of the object are?
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Programmatically generating bin files for GLTF models

I have a need to generate a series of GLB files. I have a base template for a GLTF file which I have to derive off of. The models thus generated will only have varying textures on them. The base mesh doesn't change at all. What Im stuck with Im able…
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How mesh geometry data (vertex coordinates) stored in glTF?

I've read the reference guide about the file but I am really confused. Why the hell are there "min" and "max" values ?? A single vertex has only one coordinate array not min and max.. Also in the structure of the meshes why is there an "indices"…
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Are there any gltf example datasets available?

I'm currently researching my options on effeciently exchanging data for a webgl application. I understand the gltf format is still being drafted but I need some example data to understand whether this format is really useful for my application. I'm…
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How to encode/decode buffer data in glTF?

I'm playing around with base64 embedded data URI's and tried to analyze the buffer data of the gltf box sample model, as defined in this example here (line 76). "uri":…
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How to generate binary gltf array buffers?

I'm looking for any way which enables me to quickly generate gltf files including the conversion of plain array buffers (vertex, index, color, etc.) into binary (bgltf, glb, bin) files. I'm asking because it currently looks like there are only high…
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How to apply transformation matrices from multiple primitives on a mesh

I'm working on some code to convert a 3d geometry from IFC to gltf/glb. One of the challenges I'm facing with this is that - IFC provides transformations for each primitive separately i.e., if I have a mesh (MeshA) which has 4 primitives, i'm…
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glTF animation keyframe question

I have an animated cube with 5 keyframes and when I export it to glTF with blender, in the file I can only see 3 keyframes: But when I viewed the gltf model with viewer all 5 keyframes worked well in the animation. Whats the explanation of this ?…
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Double quaternion skinning artifacts

This is technically about PGA motors, but dual quaternions are a subalgebra of PGA so for all given purposes it's the same idea. I have an animation in gltf, specified as inverse bind pose matrices, quaternions and translations. I am turning that…
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Inspecting gltf animation data

I am trying to load gltf data onto an engine I am making and I am noticing that something is wrong with the rotations. I want to be able to see the raw numeric values of the animation data in the gltf source file to compare against what my code is…
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When and who introduced the idea of a scene graph?

Simple question: is there a source that precedes the idea of presenting graphical application or 3D scene in a scene graph? I came across Hierarchical geometric models for visible surface algorithms which introduces the idea of having the geometry…
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What's the simplest, open, animation format?

I have an obj parser that handles triangle meshes specifically. I want to extend it (and the rest of my system) to handle animations as well. However, I don't think I am ready to tackle the glTF format. Because it seems to encompass much more than…
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Convert a .X mesh to a modern format

I have a bunch of meshes in the .X format, which isn't supported by many 3D applications today. Therefore, I would like to convert these to a modern format like fbx or gltf/glb. Since these meshes are proprietary, an offline solution would be…
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