How to create a DAE file to use in SceneKit?

Question

How do you create a .dae file from a 3D model? I've created a 3D model from a drone areal mapping and now have a very large file I can import in to Photoshop, but I can't figure out how to create a .dae file I can use in SceneKit.

The default game example for Xcode has a SceneKit that shows a rotating aircraft, and the asset is a .dae file, but I don't see any documentation on how to create one of those from a 3D model, and how to correctly apply a texture to it.

Answer 1

To create a 3D model and export it as a Collada .dae file you can use any of the following 3D authoring tools: Autodesk Maya, Blender, Autodesk 3dsMax, The Foundry Modo, Maxon Cinema 4D, SideFX Houdini, etc. The simplest way is to use a non-commercial student version of Autodesk Maya 2024. It's free. You can download it from HERE.

There are countless examples in YouTube how to model and uv-map in Maya software. Look at this example of UV-mapping in Maya. So, when your 3D model (and its UV-texture) is ready for use, you can export it as one of the five formats supported by SceneKit:

• animated Collada DAE
• animated Pixar USDZ
• animated Autodesk FBX
• single-frame Sony Alembic
• single-frame Wavefront OBJ with MTL

For exporting DAE models, in Maya Export Type choose DAE_FBX export:

You can export a 2K UV-mapped texture as JPEG or PNG file.

You must assign this UV-mapped square texture to a Diffuse slot of properties in Lighting Model (shader) in Show the Material Inspector.

And here's how you can do it programmatically:

import SceneKit

let scene = SCNScene(named: "art.scnassets/mushroom.scn")!

let mushroom = scene.rootNode.childNode(withName: "mushroom", 
                                     recursively: true)!

let mushroomMaterial = SCNMaterial()
mushroomMaterial.diffuse.contents = UIImage(named: "mushroom.png")
mushroom.geometry.materials = [mushroomMaterial]

P. S.

Working with Pixar's USDZ file format:

If you need to generate .usdz file, use the following command in Terminal:

usdzconvert file.fbx

Here you can read about usdzconvert command.