Bug: SegFault on conversion (k-means webgpu)

Segfault during k-means webgpu on v0.8.0 Linux

GPU segfault

Summary: Running splat-transform v0.8.0 on a .ply crashes with a segmentation fault right after the k-means step.

The run also floods stdout with millions of Dawn/Node-WebGPU getWgslLanguageFeatures: Unknown WGSLLanguageFeatureName lines. Maybe not causing direct issue, but could be relevant.

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Command used

splat-transform <REDACTED_INPUT>.ply --filterNaN -i 2 <REDACTED_OUTPUT_DIR>/meta.json
# (original run redirected to a log file)

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Expected behavior

Process completes and writes outputs without crashing.

Actual behavior

Process ends with Segmentation fault (core dumped) immediately after the k-means log line.

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Console output (redacted excerpt)

splat-transform v0.8.0
reading '<REDACTED_INPUT>.ply'...
writing '<REDACTED_OUTPUT_DIR>/meta.json'...
writing '<REDACTED_OUTPUT_DIR>/means_l.webp'...
writing '<REDACTED_OUTPUT_DIR>/means_u.webp'...
writing '<REDACTED_OUTPUT_DIR>/quats.webp'...
/home/runner/work/node-webgpu/node-webgpu/third_party/dawn/src/dawn/node/binding/GPU.cpp:337 getWgslLanguageFeatures: Unknown WGSLLanguageFeatureName WGSLLanguageFeatureName::0xbd06e060
/home/runner/work/node-webgpu/node-webgpu/third_party/dawn/src/dawn/node/binding/GPU.cpp:0x151 getWgslLanguageFeatures: Unknown WGSLLanguageFeatureName WGSLLanguageFeatureName::0x574d
/home/runner/work/node-webgpu/node-webgpu/third_party/dawn/src/dawn/node/binding/GPU.cpp:0x151 getWgslLanguageFeatures: Unknown WGSLLanguageFeatureName WGSLLanguageFeatureName::0xb7396080
/home/runner/work/node-webgpu/node-webgpu/third_party/dawn/src/dawn/node/binding/GPU.cpp:0x151 getWgslLanguageFeatures: Unknown WGSLLanguageFeatureName WGSLLanguageFeatureName::0x574d
/home/runner/work/node-webgpu/node-webgpu/third_party/dawn/src/dawn/node/binding/GPU.cpp:0x151 getWgslLanguageFeatures: Unknown WGSLLanguageFeatureName WGSLLanguageFeatureName::0xbf8bef3a
/home/runner/work/node-webgpu/node-webgpu/third_party/dawn/src/dawn/node/binding/GPU.cpp:0x151 getWgslLanguageFeatures: Unknown WGSLLanguageFeatureName WGSLLanguageFeatureName::0xbf8bf80a
/home/runner/work/node-webgpu/node-webgpu/third_party/dawn/src/dawn/node/binding/GPU.cpp:0x151 getWgslLanguageFeatures: Unknown WGSLLanguageFeatureName WGSLLanguageFeatureName::0xbf8c0683

/... (≈98,555,568 similar lines omitted) ...

/home/runner/work/node-webgpu/node-webgpu/third_party/dawn/src/dawn/node/binding/GPU.cpp:0x151 getWgslLanguageFeatures: Unknown WGSLLanguageFeatureName WGSLLanguageFeatureName::0xb1e1d35d
/home/runner/work/node-webgpu/node-webgpu/third_party/dawn/src/dawn/node/binding/GPU.cpp:0x151 getWgslLanguageFeatures: Unknown WGSLLanguageFeatureName WGSLLanguageFeatureName::0xb1e9720e
/home/runner/work/node-webgpu/node-webgpu/third_party/dawn/src/dawn/node/binding/GPU.cpp:0x151 getWgslLanguageFeatures: Unknown WGSLLanguageFeatureName WGSLLanguageFeatureName::0x33110f6c

WEBGPU features: float32-filterable, float32-blendable, texture-compression-bc, timestamp-query, depth-clip-control, depth32float-stencil8, indirect-first-instance, bgra8unorm-storage, rg11b10ufloat-renderable, clip-distances
Warning: DawnTexelCopyBufferRowAlignmentLimits is not supported in required limits
Warning: hostMappedPointerLimits is not supported in required limits
Powered by PlayCanvas 2.11.2 853d4aa
Running k-means clustering: dims=1 points=599745 clusters=256 iterations=2...
Segmentation fault (core dumped)

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Environment

• splat-transform: v0.8.0
• OS: Linux | Ubuntu 25.04
• GPU/Driver: RTX 3090 | nvidia driver 575.64.03
• Node version: v24.7.0
• Vulkan Instance Version: 1.4.304
• PlayCanvas (reported by splat-transform): 2.11.2 (853d4aa)

CPU only run works (Albeit it takes forever)

I also tried a CPU only run with the command:

splat-transform --no-gpu -w /input_path/input.ply --filterNaN -i 2 /output_path/meta.json

It works but takes forever (44mins on a ~45MB input ply with ryzen 7900X). The step that takes the most time is the k-mean clustering on centroid:

Running k-means clustering: dims=45 points=199915 clusters=65536 iterations=2...

So it seems to be a gpu bug only...

Start by reproducing the reported splat-transform command on Linux with the WebGPU path and compare it with the working --no-gpu run. Investigate the k-means step identified by the final log line, alongside the repeated Dawn/Node-WebGPU warnings. Done means the GPU run completes without a segmentation fault and writes its expected outputs.