Geometry Nodes: Metaball instances disappear on update or have delayed updating #99848

New Issue

Anon · 2022-07-19T21:33:07+02:00

Anon commented

2022-07-19 21:33:07 +02:00

System Information
Operating system: Windows-10-10.0.19044-SP0 64 Bits
Graphics card: NVIDIA GeForce RTX 3060/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 511.79

Blender Version
Broken: version: 3.2.1, branch: master, commit date: 2022-07-05 15:44, hash: a2d59b2dac
Worked: 3.1.2, branch: master, commit date: 2022-03-31 17:40, hash: cc66d1020c

Short description of error
Instanced metaballs using geometry nodes disappear when changing exposed values in the modifier itself or when you move the object that has the node tree, but seem to update to previous operation when changing values inside the node tree.

Exact steps for others to reproduce the error

Start a new file
Add Metaball
Shift select the default Cube and parent the Mball to it {key SHIFT LMB} > {key CTRL P}
For Cube switch Instancing from None to Vertices in object properties
Add new geometry nodes to Cube
Put Instance on Points node between input and output
Add Object Info node, pick Mball, check As Instance and connect it to the Instance socket of the Instance on Points node (at this point, everything works in 3.1.2)
Uncheck As Instance, the metaballs appear instanced on points now
Try moving the Cube or do any change in the geometry node tree: metaballs disappear

Metaballs show up, but update to previous operation:

Check As Instance
Change X scale on the Instance on Points node by clicking and dragging to something like 10, metaballs show up and update as expected
Change X scale again, but by typing in 1 manually, metaballs update in an unexpected way
Change X scale by typing again to 2, metaballs update to the previous value of 1

gn_metaball.blend

**System Information** Operating system: Windows-10-10.0.19044-SP0 64 Bits Graphics card: NVIDIA GeForce RTX 3060/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 511.79 **Blender Version** Broken: version: 3.2.1, branch: master, commit date: 2022-07-05 15:44, hash: `a2d59b2dac` Worked: 3.1.2, branch: master, commit date: 2022-03-31 17:40, hash: `cc66d1020c` **Short description of error** Instanced metaballs using geometry nodes disappear when changing exposed values in the modifier itself or when you move the object that has the node tree, but seem to update to previous operation when changing values inside the node tree. **Exact steps for others to reproduce the error** - Start a new file - Add **Metaball** - Shift select the default **Cube** and parent the **Mball** to it {key SHIFT LMB} > {key CTRL P} - For **Cube** switch *Instancing* from **None** to **Vertices** in object properties - Add new geometry nodes to **Cube** - Put **Instance on Points** node between input and output - Add **Object Info** node, pick Mball, check **As Instance** and connect it to the Instance socket of the Instance on Points node (at this point, everything works in 3.1.2) - Uncheck **As Instance**, the metaballs appear instanced on points now - Try moving the Cube or do any change in the geometry node tree: metaballs disappear Metaballs show up, but update to previous operation: - Check **As Instance** - Change X scale on the Instance on Points node by clicking and dragging to something like 10, metaballs show up and update as expected - Change X scale again, but by typing in 1 manually, metaballs update in an unexpected way - Change X scale by typing again to 2, metaballs update to the previous value of 1 [gn_metaball.blend](https://archive.blender.org/developer/F13301263/gn_metaball.blend)

Anon commented

2022-07-19 21:33:07 +02:00

Added subscriber: @vf986425

Omar Emara commented

2022-07-20 11:23:33 +02:00

Closed as duplicate of #87230

Omar Emara closed this issue

2022-07-20 11:23:33 +02:00

Omar Emara commented

2022-07-20 11:26:50 +02:00

Added subscriber: @OmarEmaraDev

Omar Emara commented

2022-07-20 11:26:50 +02:00

I have merged the report to #87230. since MetaBalls are not supported yet.
However, note that you have a dependency cycle in this file, which is causing the unexpected behavior you see:

Dependency cycle detected:
  OBMball/Transform Component/TRANSFORM_INIT() depends on
  OBCube/Geometry Component/GEOMETRY_EVAL() via 'Parent'
  OBMball/Geometry Component/GEOMETRY_EVAL() via 'Nodes Modifier'
  OBMball/Geometry Component/GEOMETRY_EVAL_INIT() via 'Object Geometry UberEval'
  OBMball/Transform Component/TRANSFORM_FINAL() via 'Metaball Motherball Transform -> Geometry'
  OBMball/Transform Component/TRANSFORM_SIMULATION_INIT() via 'Simulation -> Final Transform'
  OBMball/Transform Component/TRANSFORM_EVAL() via 'Transform Eval -> Simulation Init'
  OBMball/Transform Component/TRANSFORM_PARENT() via 'Eval'
  OBMball/Transform Component/TRANSFORM_LOCAL() via 'ObLocal -> ObParent'
  OBMball/Transform Component/TRANSFORM_INIT() via 'Transform Init'

I have merged the report to #87230. since MetaBalls are not supported yet. However, note that you have a dependency cycle in this file, which is causing the unexpected behavior you see: ``` Dependency cycle detected: OBMball/Transform Component/TRANSFORM_INIT() depends on OBCube/Geometry Component/GEOMETRY_EVAL() via 'Parent' OBMball/Geometry Component/GEOMETRY_EVAL() via 'Nodes Modifier' OBMball/Geometry Component/GEOMETRY_EVAL_INIT() via 'Object Geometry UberEval' OBMball/Transform Component/TRANSFORM_FINAL() via 'Metaball Motherball Transform -> Geometry' OBMball/Transform Component/TRANSFORM_SIMULATION_INIT() via 'Simulation -> Final Transform' OBMball/Transform Component/TRANSFORM_EVAL() via 'Transform Eval -> Simulation Init' OBMball/Transform Component/TRANSFORM_PARENT() via 'Eval' OBMball/Transform Component/TRANSFORM_LOCAL() via 'ObLocal -> ObParent' OBMball/Transform Component/TRANSFORM_INIT() via 'Transform Init' ```

Stay_Here referenced this issue

2023-06-27 05:22:19 +02:00

The number of metaballs suddenly increases more than they should be #109392

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Geometry Nodes: Metaball instances disappear on update or have delayed updating #99848