Simulation nodes freeze subframe movement of points when new points are added #115387

New Issue

Dave Whitney · 2023-11-25T01:01:12+01:00

Dave Whitney commented

2023-11-25 01:01:12 +01:00

System Information
Operating system: Windows-10-10.0.22631-SP0 64 Bits
Graphics card: NVIDIA RTX A5000/PCIe/SSE2 NVIDIA Corporation 4.6.0 NVIDIA 537.58

Blender Version
Broken: version: 4.0.1, branch: blender-v4.0-release, commit date: 2023-11-16 16:40, hash: d0dd92834a08
Worked: unknown

Short description of error
GeoNodes setup adds moving points to a scene on command. When new points are added, the existing point freeze for a single frame.

Exact steps for others to reproduce the error
Load the attached file, select the Emitter object and switch the Physics tab and click Bake. Ensure Playback has Subframes enabled. Slowly drag the playback slide from frame 4 to frame 7 and note that the green beam is sliding smoothly along. As you drag into frame 7 and toward frame 8, the beam stops moving. When you enter frame 8, a 2nd beam appears (by design) and they both being moving smoothly again. Note that the first beam abruptly jumps to where it should have been if it had been sliding smoothly all along.

Note the same happens with both beam as you slide from frame 11 to 12. The problem occurs for the preceding frame where new beams are to appear.

I have tried numerous different variations of the GeoNodes setup and I haven't found any workaround.

Note also that instead of deleting the "old" beams I am setting their scale to "very small". This is because deleting points also messes things up - usually causing some beam to slide across space to where some other beam is already.

This all seriously messes up motion blur. The problem is entirely invisible if only rendering w/o MB, or only viewing the whole frames (not subframes).

There seems to be a problem keeping the attribute values for a given point actually stuck to that point, but that doesn't explain the freezing.

**System Information** Operating system: Windows-10-10.0.22631-SP0 64 Bits Graphics card: NVIDIA RTX A5000/PCIe/SSE2 NVIDIA Corporation 4.6.0 NVIDIA 537.58 **Blender Version** Broken: version: 4.0.1, branch: blender-v4.0-release, commit date: 2023-11-16 16:40, hash: `d0dd92834a08` Worked: unknown **Short description of error** GeoNodes setup adds moving points to a scene on command. When new points are added, the existing point freeze for a single frame. **Exact steps for others to reproduce the error** Load the attached file, select the Emitter object and switch the Physics tab and click Bake. Ensure Playback has Subframes enabled. Slowly drag the playback slide from frame 4 to frame 7 and note that the green beam is sliding smoothly along. As you drag into frame 7 and toward frame 8, the beam stops moving. When you enter frame 8, a 2nd beam appears (by design) and they both being moving smoothly again. Note that the first beam abruptly jumps to where it should have been if it had been sliding smoothly all along. Note the same happens with both beam as you slide from frame 11 to 12. The problem occurs for the preceding frame where new beams are to appear. I have tried numerous different variations of the GeoNodes setup and I haven't found any workaround. Note also that instead of deleting the "old" beams I am setting their scale to "very small". This is because deleting points also messes things up - usually causing some beam to slide across space to where some other beam is already. This all seriously messes up motion blur. The problem is entirely invisible if only rendering w/o MB, or only viewing the whole frames (not subframes). There seems to be a problem keeping the attribute values for a given point actually stuck to that point, but that doesn't explain the freezing.

GeoNodes Subframes bug.blend

1.5 MiB

Dave Whitney added the

labels 2023-11-25 01:01:12 +01:00

Pratik Borhade commented

2023-11-25 05:37:36 +01:00