Material Nodes break in Eevee #56010

New Issue

Julien Kaspar · 2018-07-17T11:57:42+02:00

Julien Kaspar commented

2018-07-17 11:57:42 +02:00

Blender Version
Broken: dc3b3d9453

Description of error
When I work with the Eevee Material View to work on complex materials that have many nodes influence multiple different material inputs, at some point the complexity gets to high and the material breaks for Eevee. When rendered in Cycles this bug doesn't happen.

I first saw this with the red jacket for the character Spring: /media/data/spring/lib/char/spring/spring.blend
When only, for example, the node tree is plugged into the diffuse and normal inputs of the Principled BSDF shader, then everything looks like it's supposed to.

Add the node tree to the Specular input and I believe one of the "Hue Saturation Value" Nodes breaks (in the red "Texture: Main Color" node frame).

Connect the node tree to the roughness input and the same or more nodes start to break:

If I start changing the node tree, muting certain nodes that I think cause the bug, other nodes seem to break instead:

In another file, the alpha creature, this happened as well: /media/data/spring/lib/char/alpha/alpha.blend

The material became more and more complex and once I added another Color Mix node to add more white frost to certain areas, some other node mixing the darker parts of the diffuse color gave up.

I added another mask for the frost and it got even worse:

**Blender Version** Broken: dc3b3d94538 **Description of error** When I work with the Eevee Material View to work on complex materials that have many nodes influence multiple different material inputs, at some point the complexity gets to high and the material breaks for Eevee. When rendered in Cycles this bug doesn't happen. I first saw this with the red jacket for the character Spring: /media/data/spring/lib/char/spring/spring.blend When only, for example, the node tree is plugged into the diffuse and normal inputs of the Principled BSDF shader, then everything looks like it's supposed to. ![Selection_069.png](https://archive.blender.org/developer/F3977231/Selection_069.png) Add the node tree to the Specular input and I believe one of the "Hue Saturation Value" Nodes breaks (in the red "Texture: Main Color" node frame). ![Selection_070.png](https://archive.blender.org/developer/F3977245/Selection_070.png) Connect the node tree to the roughness input and the same or more nodes start to break: ![Selection_071.png](https://archive.blender.org/developer/F3977257/Selection_071.png) If I start changing the node tree, muting certain nodes that I think cause the bug, other nodes seem to break instead: ![Selection_072.png](https://archive.blender.org/developer/F3977263/Selection_072.png) In another file, the alpha creature, this happened as well: /media/data/spring/lib/char/alpha/alpha.blend ![Selection_066.png](https://archive.blender.org/developer/F3977284/Selection_066.png) The material became more and more complex and once I added another Color Mix node to add more white frost to certain areas, some other node mixing the darker parts of the diffuse color gave up. ![Selection_067.png](https://archive.blender.org/developer/F3977288/Selection_067.png) I added another mask for the frost and it got even worse: ![Selection_068.png](https://archive.blender.org/developer/F3977294/Selection_068.png)

Julien Kaspar commented

2018-07-17 11:57:42 +02:00

Added subscriber: @JulienKaspar

Bastien Montagne commented

2018-07-17 14:48:17 +02:00

Added subscribers: @fclem, @mont29

Clément Foucault was assigned by Bastien Montagne

2018-07-17 14:48:17 +02:00

Bastien Montagne commented

2018-07-17 14:48:17 +02:00

You may just hit the limitation of GPU shaders… ;)
@fclem shall know more about that!

You may just hit the limitation of GPU shaders… ;) @fclem shall know more about that!

Clément Foucault commented

2018-07-17 17:10:05 +02:00

Long story short, you only have between 16 and 32 available texture slots when rendering with opengl (depending on the GPU).
Eevee's shadowmaps and other utility texture already take up 5+ of them so you have even less to work with.

The real bug here is that there is nothing telling the user there is a limitation that has been reached.

Ah and remember that color ramp and curves count as textures :)

Long story short, you only have between 16 and 32 available texture slots when rendering with opengl (depending on the GPU). Eevee's shadowmaps and other utility texture already take up 5+ of them so you have even less to work with. The real bug here is that there is nothing telling the user there is a limitation that has been reached. Ah and remember that color ramp and curves count as textures :)

Brecht Van Lommel commented

2018-07-17 17:56:29 +02:00

Added subscriber: @brecht

Brecht Van Lommel commented

2018-07-17 17:56:29 +02:00

Bindless textures can solve that limitation on modern GPUs, though that probably goes beyond a bug report and into new features.

Julien Kaspar commented

2018-07-17 18:12:34 +02:00

This is weird to me since I am only using 7 custom textures in the alpha creature material and I believe even less in the jacket. What qualifies as a texture? Do procedural textures count? If a texture is used for multiple different channels like diffuse, bump, specular, does it count as one for each? If yes then that seems like a big problem to me since the most efficient way to texture paint is to use one map for as many material inputs as possible.

Edit: Just now read that color ramps and curves count too. My question about the channels still stands though.

This is weird to me since I am only using 7 custom textures in the alpha creature material and I believe even less in the jacket. What qualifies as a texture? Do procedural textures count? If a texture is used for multiple different channels like diffuse, bump, specular, does it count as one for each? If yes then that seems like a big problem to me since the most efficient way to texture paint is to use one map for as many material inputs as possible. Edit: Just now read that color ramps and curves count too. My question about the channels still stands though.

Clément Foucault commented

2018-07-17 20:17:00 +02:00

@brecht yes I'm aware and did not want to talk about this here.

@JulienKaspar It seems that if the texture is the same it uses the same sampler. I will take a look at what causes the problem on your specific files. There should be an error message in the terminal if you have this sampler limit problem.

Something I would like to do is to group all the color ramps and curves into one texture. That would lower the sampler count drastically on production shaders.

@brecht yes I'm aware and did not want to talk about this here. @JulienKaspar It seems that if the texture is the same it uses the same sampler. I will take a look at what causes the problem on your specific files. There should be an error message in the terminal if you have this sampler limit problem. Something I would like to do is to group all the color ramps and curves into one texture. That would lower the sampler count drastically on production shaders.

Julien Kaspar commented

2018-07-17 20:40:59 +02:00

I counted on the alpha material and with the colorramps and curves it leads to 28 textures. That should match with the texture limit. We use colorramps and curves a lot, so I agree it would be fantastic if those could be grouped. If that even makes the jacket material work, then that would be great. That one is needlessly complicated anyway but I think this will happen rather often when texturing and if Eevee can handle that then that would make it even more powerful for texturing/shading previews!

blender-admin commented

2018-08-10 15:13:39 +02:00

This issue was referenced by bf6a22ed6f

This issue was referenced by bf6a22ed6f6bbe7db3e7796e83d32e071aae93cc

Clément Foucault commented

2018-08-10 16:20:54 +02:00

Changed status from 'Open' to: 'Resolved'

Clément Foucault closed this issue

2018-08-10 16:20:54 +02:00

Sign in to join this conversation.

No Label

Download

What's New

Blender Studio

Manual

Developers Blog

Documentation

Benchmark

Blender Conference

Development Fund

One-time Donations

Material Nodes break in Eevee #56010