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Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · 4d

gist.github.com/Matt54/f001a...

PLY to RealityKit with Grid-Based Decimation (Example: HD Skeleton Scan)

PLY to RealityKit with Grid-Based Decimation (Example: HD Skeleton Scan) - ModelIOLoader.swift

gist.github.com

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Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · 4d

RealityKit experiment #81
(code in the replies)

I found a scan of a human skeleton and wanted to try to visualize it in RealityKit. The PLY file had millions of triangles, so I had to decimate the mesh. It ended up being really satisfying to see the wireframe at different LODs

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Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · 6d

Thanks Clem! I would love to see that Gaussian Splat example

1

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · 7d

gist.github.com/Matt54/afc92...

RealityKit SDF Falling Sand Animation (Metal + LowLevelMesh + Marching Cubes)

RealityKit SDF Falling Sand Animation (Metal + LowLevelMesh + Marching Cubes) - EasingCurve.swift

gist.github.com

1

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · 7d

RealityKit experiment #80
(gist in the replies)

LowLevelMesh “Falling Sand” dissolution and reassemble effect created with SDF shapes and Marching Cubes. A Metal compute shader uses a spatial sweep to "release" triangles that rigidly start to fall

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Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · 14d

gist.github.com/Matt54/44177...

RealityKit Extruded Text to LowLevelMesh animated by Metal compute shader

RealityKit Extruded Text to LowLevelMesh animated by Metal compute shader - ExtrudedTextLowLevelMeshView.swift

gist.github.com

1

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · 14d

RealityKit experiment #79
(code in the replies)

Animating 3D text by converting the output of MeshResource(extruding:) to a LowLevelMesh and applying a Metal compute shader

The MeshResource was interesting to unpack since it had multiple models/parts plus instance transforms

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Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · 21d

Thank you! 🙏

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · 21d

gist.github.com/Matt54/87edc...

RealityKit Explode and Assemble SDF Shape (Metal + LowLevelMesh + Marching Cubes)

RealityKit Explode and Assemble SDF Shape (Metal + LowLevelMesh + Marching Cubes) - EasingCurve.swift

gist.github.com

1 2

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · 21d

RealityKit experiment #78
(gist in the replies)

LowLevelMesh explode-and-assemble animation created by meshing an SDF using Marching Cubes and rigidly pushing it’s triangles outward

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Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Aug 29

gist.github.com/Matt54/bcc31...

RealityKit Color-Blending Metaballs (Metal + LowLevelMesh + Marching Cubes)

RealityKit Color-Blending Metaballs (Metal + LowLevelMesh + Marching Cubes) - MarchingCubesColorBlobParams.h

gist.github.com

1 2

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Aug 29

RealityKit experiment #77
(gist in the replies)

Color-blending metaballs created from animated sphere SDFs via Marching Cubes. LowLevelMesh vertices store per-vertex color in the Geometry Color vertex attribute, read by ShaderGraphMaterial

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Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Aug 20

Ahhh, well I love that description 😆

1

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Aug 20

Is it the room?

1

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Aug 20

gist.github.com/Matt54/1a506...

RealityKit Marching Cubes Blob (Metal + LowLevelMesh)

RealityKit Marching Cubes Blob (Metal + LowLevelMesh) - MarchingCubesBlobParams.h

gist.github.com

3

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Aug 20

RealityKit experiment #76
(gist in the replies)

LowLevelMesh blob from meshing the smooth-min of animated sphere SDFs with marching cubes. Glassy ShaderGraphMaterial is based on Apple's "Implementing adjustable material" sample

4 3 17

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Aug 13

Haha exactly 😆

1

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Aug 13

gist.github.com/Matt54/aec7d...

gist.github.com

1

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Aug 13

RealityKit experiment #75
(gist in the replies)

LowLevelMesh shape shifting by interpolating between two signed distance fields and meshing with marching cubes

3 7 29

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Aug 8

gist.github.com/Matt54/881d7...

Marching Cubes Metaballs in RealityKit (Metal + LowLevelMesh)

Marching Cubes Metaballs in RealityKit (Metal + LowLevelMesh) - MarchingCubesParams.h

gist.github.com

3

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Aug 8

RealityKit experiment #74
(gist in the replies)

- LowLevelMesh with disconnected geometry
- Marching Cubes + SDF for vertex positions
- Vertex normals from SDF gradient
- Polynomial smooth-min to blend the shapes

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Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Jul 22

gist.github.com/Matt54/bf9d1...

RealityKit burn fade sphere: LowLevelMesh, ShaderGraphMaterial, and compute shader

RealityKit burn fade sphere: LowLevelMesh, ShaderGraphMaterial, and compute shader - BurnFadeParams.h

gist.github.com

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Jul 22

RealityKit experiment #73
(gist in the replies)

Here's a simple burn fade example. The ShaderGraphMaterial directly sets the color and opacity from the UV2 attribute of the LowLevelMesh vertices and the Metal compute shader updates those color/opacity values

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Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Jul 20

Yeah that makes sense

The idea came to me while building a glowing torus for a project and I just wanted to see how it would look as a spinner. Performance is probably not good 😆

1

Matt Pfeiffer ᯅ @mattpfeiffer.bsky.social · Jul 20

gist.github.com/Matt54/20595...

RealityKit LowLevelMesh Glowing Torus Spinner

RealityKit LowLevelMesh Glowing Torus Spinner. GitHub Gist: instantly share code, notes, and snippets.

gist.github.com