Load glTF model into RealityKit scene? - augmented-reality

I'd like to load a glTF file generated by another program into RealityKit. I get the impression that the only way to load models into RealityKit is via USD or Reality files.
Anyone know a way to get some other model into RealityKit? Not necessarily as a file -- I'd be happy to be able to generate a MeshResource and array of Materials myself and load them in that way.

Reality Converter
Apple discussed this in the WWDC20 video "The artist’s AR toolkit".(link)
They show how to convert FBX, OBJ, USD and GLTF files to USDZs for use in Reality Composer.
Reality Converter is still in beta and needs to be downloaded from the Apple Developer website. I used it and it is quite nice.
There is also other tools you can use on the command line if this is more your thing. At WWDC 2019, Apple announced the USDZ Tools or also called USD Python Tools.
USDZ Tools is a pre-compiled Python library containing binaries of Pixar’s USD library for macOS. This is the link. You will need to download and install the library.
I would give a try to the Reality Converter first. I think it is here to stay since probably Apple has no intention to add support for glTF files in Reality Composer in the future, since they love USBZ!

I ended up using GLTFKit, an open source library by Warren Moore. It does exactly what I want -- lets me load a glTF file into SceneKit/RealityKit.
https://github.com/warrenm/GLTFKit

Alas, as you said, at the moment the only way to load your .gltf model in RealityKit scene – is firstly to convert it into .usdz model via Xcode command line tools. Also in RealityKit you can use .reality format (use it for a much faster uploading time) and .rcproject format that can be exported from Reality Composer app. These two file formats allow you store not only PBR shaders and animation but also a dynamics.
Please, read this post for further details.

Related

Convert ( .obj / .fbx ) to .dae runtime which must support iOS SceneKit

I am facing trouble to find a way to convert .obj / .fbx to .dae (iOS scenefit Supported) automatically in background.
In python, it may be available to convert the file from .obj / .fbx to .dae file format. This process should run in background, immediately run after we will get .obj / .fbx file on server.
Here is the sample file, which we are trying to convert.
https://s3.ap-south-1.amazonaws.com/p9-platform/DAE/barware_s11624.obj
Please help me, if you have any suggestion.
Scenekit on IOS doesn’t support dae unless it was included in the app. So because of the “iOS Scenekit Supported” requirement there is no right answer, sort of. Although there are third party libraries (like https://github.com/dmsurti/AssimpKit ) to read and convert many 3d model formats, it won’t change the fact dae isn’t properly supported on IOS Scenekit .
That said, it is possible to convert OBJ to DAE in SceneKit using the following steps (in IOS 11.2 and later)
Load the obj file into a SCNScene.
Write the scene to a file with .dae extension using SCNScene’s writeToURL method.
That will create a .dae file SceneKit can support (but not directly, i.e. would need to be included in xcode or converted first) that starts with the following:
<?xml version="1.0" encoding="UTF-8"?>
<COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
<asset>
<contributor>
<authoring_tool>SceneKit Collada Exporter v1.0</authoring_tool>
</contributor>
I would second the recommendation for using Assimp or AssimpKit (I’ve only used the former but the latter might be an easier starting point).
I believe the DAEs on iOS aren’t DAEs at all, they just left the suffix the same and the actual files are SceneKit archives. I’m not sure if the API to write them is exposed yet, but I think it might be now since Xcode is now willing to load DAEs and write out SceneKit archives (but it adds the “.scn” suffix, not “.dae”).
It’s possible that iOS SceneKit can just load “.scn” files — it won’t load true DAEs because the DEA-reading/writing framework was licensed from Sony and is HUGE and the iOS team just doesn’t want that giant ugly framework on its system.
Another option would be to just link the iOS app against Assimp — it can load a ton of formats natively so you could skip all the intermediate stuff. It’s not NEARLY as huge as Sony’s DAE library so it might be acceptable to ship it with your app.

Dynamic 3DObject use in ARKit-SceneKit

I want to download the 3D Object-dae(collada) file from server and want to display on surface dynamically so can please share how can I achieve this in ARKit via SceneKit or else?
You can check this link: https://the-nerd.be/2014/11/07/dynamically-load-collada-files-in-scenekit-at-runtime/ it is old post but I don't think something is changed since that
According to this (see the Discussion section): https://developer.apple.com/documentation/modelio/mdlasset/1391813-canimportfileextension?language=objc
dae is not supported at runtime (ModelIO).
Additionally I'm working on a library called AssetKit (In Progress) and it will full support COLLADA and glTF, it is too early to say that but after initial release, you will be able to load dae files dynamically. It is written with C99 but I'll optimize it for Swift (by writing wrappers or integration with SceneKit...). Since it is still in progress I suggest that follow the first link

Use FBX file with 3D model in iOS native app

I have a requirement to display an interactive 3D model (the client supplies few FBX files) in one of the screens in a native Objective-C/Swift app.
I know that there's a possibility to work with Unity/Cocos3D but then the entire app will have to be Unity/Cocos3D based. In my case the app has to be native and only one screen (one of the tabs in the tab bar controller) should integrate the 3D model that the user can move/rotate etc.
Thanks.
The FBX SDK is available on iOS and I wrote a little tutorial to demo how to use it here. However, the FBX SDK does contain a viewport/canvas for displaying FBX file on any OS. For displaying FBX you would need to create your own view. There is couple of solutions you can use here:
without programming, you can use the 'FBX Review'. This tools is free and designed to display FBX, DAE, OBJ, ... files
you can implement your own viewport/view such as an obj view like I did here, but it would probably need to be rewritten. I wrote it overnight for a hack, so it needs to be optimized.
you use the iOS SceneKit library which would be a better approach than implementing your own view.
If you go with option 3 above, you can use Unity to export a Collada (.dae) file for importing into SceneKit thru the collada exporter. You can buy the exporter on the Unity Asset Store directly; there's one for Unity 5.x and one for Unity 2017.

ios : Displaying a simple 3D model with GLEssentials sample code

My goal is to display a simple 3D model and apply a texture on it.
I've downloaded the GLEssentials ios sample project to learn how to develop this (i'm new in ios OpenGL-ES API)
But the example model is a .model file, which I never heard about and which never appear in model bank websites.
What is this kind of file?
is the sample code compatible with other common model types (.obj, .c2d, .3ds)?
is it a good idea to start from this project?
Have a look at this question:
How to convert Blender blend (or obj) file to Qualcom Vuforia .h file
In my answer, I describe a script and accompanying Xcode project that converts .obj/.mtl files to header files suitable for OpenGL ES on iOS [link].
In response to your questions:
I believe the .model file is only appropriate for the sample project and is a proprietary Apple extension. It most likely contains simple data such as vertex positions.
I think you'd struggle to fit other model types into the sample code, which is very complex for OpenGL ES beginners. You might want to have a look at .pod files on Cocos2D here. I've seen and heard great things about it.
I wouldn't recommend it :)

Loading 3D model in iOS

I'm creating a game application from scratch with xcode for iOS, and I've use the OpenGL Game projet template to create mine.
I've searched a lot in the past few days, but I can't find any tutorials or example as to how I would load 3D model (via .obj files) in my application. I've found some documentation on loading them onto an app with a console script, but I need to do it programmatically.
Any help would be very appreciated
Also, my 3D models are created using blender
The future will be here momentarily — SceneKit, available in OS X since v10.8, will be in iOS 8. It can build and render a scene with COLLADA (.DAE) models directly. No need for third-party tools or code, nothing complicated to learn.
Apple's documentation is pretty good but if you prefer then other tutorials are available.
OpensceneGraph has support for iOS and a lot of prebuilt code which can help you develop the game. It supports loading OBJ models.
I recommend to use an Engine (like isgl3d, nineveh, Cocos3D, ...) for creating a 3D game, it will be hard if you use Opengl for a start.
Note: you can search for a list of game engine to choose the suitable one for you game, cause there is a lot of game engine, open-source or paid engine.
You can download the zip file from here and then run ./obj2opengl.pl 3DModel.obj in terminal .It will give you 3DModel.h file as output.
You need to use glDrawArrays instead of glDrawElements as the .h file contains array.
Obj files are simple to parse and are well described on wikipedia. You should be able to load them in one or 2 hours. But if you want to load the materials you need to invest some more time in your engine and into loading the obj file.

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