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.
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Issues understanding rotations exported from Blender to gltf
I am trying to write a raytracer in Rust that is able to load a .gltf file and render it. To do this I model a scene in Blende, export it to gltf (y up) and use my renderer to render the scene.
The ...
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How to properly use the BRDF from glTF 2.0 specification in path tracing while using metallic/roughness materials?
I've built a renderer which should render glTF materials, as they are defined in their specification. So I should be able to render satisfying (similar to Cycles and Ospray) results just from the base ...
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How does one construct a 3D file format from pixels and vertices? [closed]
I have searched around in a lot of places but I have yet to find some place that explains 3D file formats in a way that aligns with the model I have right now. I have a simple problem (I think) but it'...
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Loading Gltf model pbr texture produces insane results
I built a gltf-viewer on my own, but the functionality for loading glf was implemented by referencing gltf-viewer-tutorial, the result is not correct. Below is my ouput for ToyCar.gltf .
The ouput of ...
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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, ...
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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 ...
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Starting from a basic glTF (such as a static sphere or plane) exported from Blender how can I add an animation manipulating its JSON?
I'm working on a glTF, precisely I'm trying to animate a "static" mesh exported from Blender directly acting on its JSON.
In doing so, I'm following the logic used in this tutorial , where a ...
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How to apply a linear transformation to gltf data
I am trying to transform the mesh data in a gltf file and then modify the skin and animation data accordingly.
Let's say we want to transform the data using a 4x4 homogeneous matrix. For ...
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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 ...
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Uploading interleaved data in gltf buffers
Suppose a GLTF file provides a single N byte buffer which includes all vertex data for multiple meshes. The first m bytes are ...
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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 ...
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Why are these 2 buffers joint while extracting glTF information?
I am using tinyGLTF to parse gltf files and then render them in my program.
I am currently during the third example in this page.
In particular I am trying to extract the 2 animation buffers:
My code:...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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).
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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 ...
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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 ...
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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 (...
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Are there any gltf example datasets available? [closed]
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 ...
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