Fourth and subsequent vertex color / UV layers displayed black #60684

New Issue

Marcelo Demian Gómez · 2019-01-20T21:58:23+01:00

2019-01-20 21:58:23 +01:00

System Information
Operating system: Ubuntu 18.04
Graphics card: GeForce GTX 1070

Blender Version
Broken: 2.8 2019-01-19 b0dee09a6d
Worked: 2.79

Short description of error
After creating more than 3 vertex color layers on an object, the fourth and all of the following are displayed completely black.

Exact steps for others to reproduce the error

Start blender with the default startup.
Switch to Vertex Paint Mode.
Open the "Object Data" Tab in the Properties Editor
In the Vertex Colors Panel, add three more Vertex Color layers -> The fourth is displayed black.

**System Information** Operating system: Ubuntu 18.04 Graphics card: GeForce GTX 1070 **Blender Version** Broken: 2.8 2019-01-19 b0dee09a6d55 Worked: 2.79 **Short description of error** After creating more than 3 vertex color layers on an object, the fourth and all of the following are displayed completely black. **Exact steps for others to reproduce the error** 1) Start blender with the default startup. 2) Switch to Vertex Paint Mode. 3) Open the "Object Data" Tab in the Properties Editor 4) In the Vertex Colors Panel, add three more Vertex Color layers -> The fourth is displayed black.

Marcelo Demian Gómez commented

2019-01-20 21:58:23 +01:00

Added subscriber: @MarceloGomez

blender-admin commented

2019-01-20 21:58:23 +01:00

#61223 was marked as duplicate of this issue

blender-admin commented

2019-01-20 21:58:23 +01:00

#60797 was marked as duplicate of this issue

Philipp Oeser commented

2019-01-21 10:49:58 +01:00

Added subscriber: @lichtwerk

Philipp Oeser commented

2019-01-21 10:49:58 +01:00

Confirmed, checking...

Philipp Oeser commented

2019-01-21 13:02:15 +01:00

Added subscriber: @fclem

Philipp Oeser commented

2019-01-21 13:02:15 +01:00

Same is true for UVMaps (fourth one is also displayed 'blank')

Note it actually renders fine on F12 [the vertex color case, for UVs, the fourth also fails on F12 render]

Before digging deeper: @fclem: do you want me to dive deeper or is this one for you right away?

Same is true for UVMaps (fourth one is also displayed 'blank') Note it actually **renders** fine on F12 [the vertex color case, for UVs, the fourth also fails on F12 render] Before digging deeper: @fclem: do you want me to dive deeper or is this one for you right away?

Clément Foucault commented

2019-01-21 15:19:15 +01:00

@lichtwerk You can go ahead and dig deeper. That does not ring any bell from me.

Philipp Oeser self-assigned this 2019-01-21 16:02:48 +01:00

Philipp Oeser commented

2019-01-21 16:02:48 +01:00

OK, will do some checking...

Philipp Oeser commented

2019-01-24 09:15:50 +01:00

Added subscribers: @0rAngE, @WilliamReynish

Philipp Oeser changed title from ~~Fourth and subsequent vertex color layers displayed black~~ to Fourth and subsequent vertex color / UV layers displayed black

2019-01-28 14:08:18 +01:00

Philipp Oeser removed their assignment 2019-02-01 14:04:45 +01:00

Clément Foucault was assigned by Philipp Oeser

2019-02-01 14:04:45 +01:00

Philipp Oeser commented

2019-02-01 14:04:45 +01:00

OK, this already turned into a major timesink for me, so I'm afraid I have to bounce this back to @fclem

But here are some findings (not sure if they are related though):

This was caused by the port to batch request (a68edaf11d). Prior to that, all layers displayed correctly.
I think I dont quite get the logic [here ]] (in conjunction with the alias [ https:*developer.blender.org/diffusion/B/browse/master/source/blender/draw/intern/draw_cache_impl_mesh.c$3228 | here ). For properly displaying vcol layers rdata->cd.layers.vcol_active is always decrementing to zero, not so for the "failing" ones...
also tried checking usages of mesh_cd_layers_type_merge and mesh_cd_layers_type_overlap in conjunction with local functions cd_lneeded[CD_MLOOPCOL] vs cache->cd_lneeded[CD_MLOOPCOL] but couldnt find anything suspicious there...

@fclem: mind taking over?

OK, this already turned into a major timesink for me, so I'm afraid I have to bounce this back to @fclem But here are some findings (not sure if they are related though): - This was caused by the port to batch request (a68edaf11d). Prior to that, all layers displayed correctly. - I think I dont quite get the logic [here ]] (in conjunction with the alias [[ https:*developer.blender.org/diffusion/B/browse/master/source/blender/draw/intern/draw_cache_impl_mesh.c$3228 | here ](https:*developer.blender.org/diffusion/B/browse/master/source/blender/draw/intern/draw_cache_impl_mesh.c$892)). For properly displaying vcol layers `rdata->cd.layers.vcol_active` is always decrementing to zero, not so for the "failing" ones... - also tried checking usages of `mesh_cd_layers_type_merge` and `mesh_cd_layers_type_overlap` in conjunction with local functions `cd_lneeded[CD_MLOOPCOL]` vs `cache->cd_lneeded[CD_MLOOPCOL]` but couldnt find anything suspicious there... @fclem: mind taking over?

Clément Foucault commented

2019-02-01 16:03:03 +01:00

taking this over