Point Distribute inconsisntency #86085

New Issue

Iván Barták · 2021-02-28T15:30:47+01:00

Iván Barták commented

2021-02-28 15:30:47 +01:00

System Information
Operating system: Windows-10-10.0.18362-SP0 64 Bits
Graphics card: GeForce GTX 1060 with Max-Q Design/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 457.51

Blender Version
Broken: version: 2.92.0, branch: master, commit date: 2021-02-24 16:25, hash: 02948a2cab

Short description of error
Point Distribute node seems to work inconsistently with transformations, in relative mode:

Rotation affects only Z axes (rotates around the normal vector of the object).
Scale effects the distribution distance and the scattered object size as well.
Location does not have any effect.

User story
I tried to animate markers on the map, they appeared by scaling up, and I scattered random lines from the marker to different, random points on the map. And the number of scattered lines changed with the scale animation. (at zero scale it was around infinite lines, and Blender froze). I separated the lines to a different object, and parented both to an empty, and scaled the marker separately for workaround.
Exact steps for others to reproduce the error
Open the attached blend file, and examine the cubes.
scatter_relative_point_distribution.blend

**System Information** Operating system: Windows-10-10.0.18362-SP0 64 Bits Graphics card: GeForce GTX 1060 with Max-Q Design/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 457.51 **Blender Version** Broken: version: 2.92.0, branch: master, commit date: 2021-02-24 16:25, hash: `02948a2cab` **Short description of error** Point Distribute node seems to work inconsistently with transformations, in relative mode: - Rotation affects only Z axes (rotates around the normal vector of the object). - Scale effects the distribution distance and the scattered object size as well. - Location does not have any effect. ![scatter_node_inconsistency.jpg](https://archive.blender.org/developer/F9852292/scatter_node_inconsistency.jpg) **User story** I tried to animate markers on the map, they appeared by scaling up, and I scattered random lines from the marker to different, random points on the map. And the number of scattered lines changed with the scale animation. (at zero scale it was around infinite lines, and Blender froze). I separated the lines to a different object, and parented both to an empty, and scaled the marker separately for workaround. **Exact steps for others to reproduce the error** Open the attached blend file, and examine the cubes. [scatter_relative_point_distribution.blend](https://archive.blender.org/developer/F9852302/scatter_relative_point_distribution.blend)

Iván Barták commented

2021-02-28 15:30:47 +01:00

Added subscriber: @Montaire

Philipp Oeser commented

2021-03-17 12:06:30 +01:00

Added subscriber: @lichtwerk

Philipp Oeser commented

2021-03-17 12:06:30 +01:00

Changed status from 'Needs Triage' to: 'Needs User Info'

Philipp Oeser commented

2021-03-17 12:06:30 +01:00

I think this is all expected behavior.

To compensate, you have Location, Rotation and Scale exposed to you via the Object Info node and with some calculations, you can achieve what you want using the Point Rotate, Point Scale and Point Translate nodes.
The case of distribution when scaling can be tamed to some extend (using some fiddling with Distance Min & Distance Max), but this wont work stable with scaling I think (and is not really supposed to , so that wont be considered a bug I think).

scatter_relative_point_distribution_tweak.blend

Does this work for you?

I think this is all expected behavior. To compensate, you have `Location`, `Rotation` and `Scale` exposed to you via the `Object Info` node and with some calculations, you can achieve what you want using the `Point Rotate`, `Point Scale` and `Point Translate` nodes. The case of distribution when scaling can be tamed to some extend (using some fiddling with `Distance Min` & `Distance Max`), but this wont work stable with scaling I think (and is not really supposed to , so that wont be considered a bug I think). [scatter_relative_point_distribution_tweak.blend](https://archive.blender.org/developer/F9896260/scatter_relative_point_distribution_tweak.blend) Does this work for you?

Iván Barták commented

2021-03-21 15:59:56 +01:00

Thank you! It is working well with the Point nodes.

It is still not clear, how attributes different from Point nodes exactly.
Maybe it would be nice to have a description what exactly a Point is, and how different from the mesh attributes.

Than I may could understand why those transformations act so differently, and use this behaviour purposely.

(Till now I tough they are both just modifying vertexes.
So Mesh attributes modifying the vertexes in the distributed meshes, Points are the origins of distributed objects?)

Thank you! It is working well with the Point nodes. It is still not clear, how attributes different from Point nodes exactly. Maybe it would be nice to have a description what exactly a Point is, and how different from the mesh attributes. Than I may could understand why those transformations act so differently, and use this behaviour purposely. (Till now I tough they are both just modifying vertexes. So Mesh attributes modifying the vertexes in the distributed meshes, Points are the origins of distributed objects?)

Ankit Meel commented

2021-03-30 16:27:12 +02:00

Added subscriber: @ankitm