Discrepancy between material preview & render in Cycles and EEVEE with specific node setup #70775

New Issue

XanTheDragon · 2019-10-13T01:04:08+02:00

XanTheDragon commented

2019-10-13 01:04:08 +02:00

n.b. This is NOT an issue related to the known differences between Cycles and EEVEE regarding material node compatibility or appearance due to the presence (or lack of) raytracing.

System Information
Operating system: Windows 7 64-bit
Graphics card: Nvidia GTX 1070

Blender Version
Broken: v2.80

Short description of error
A node setup that replaces certain colors on a texture is functional in the Material Preview (on both Cycles and EEVEE), but shows incorrectly in Cycles renders.

Exact steps for others to reproduce the error
To reproduce:

Open the attached .blend file. The image texture necessary should be packed inside.
Ensure the model has the proper material applied to it, Material.001. Its node layout should be an image texture, a custom group node, a Principled BSDF, and a material output from left to right.
Ensure the current renderer is set to Cycles.
Change the viewport shading mode to Look Dev. The stripe on the top of the head and rings on the ears should appear red.
Change the renderer to EEVEE. The appearance should remain unchanged.
Change the viewport shading mode to Rendered. The appearance should remain unchanged.
Change the renderer to Cycles. The stripe on the top of the head and rings on the ears will now appear pink (as shown in the original texture) rather than displaying the red color created by the material's node output.

BugRepro.blend

n.b. This is *NOT* an issue related to the known differences between Cycles and EEVEE regarding material node compatibility or appearance due to the presence (or lack of) raytracing. **System Information** Operating system: Windows 7 64-bit Graphics card: Nvidia GTX 1070 **Blender Version** Broken: v2.80 **Short description of error** A node setup that replaces certain colors on a texture is functional in the Material Preview (on both Cycles and EEVEE), but shows incorrectly in Cycles renders. **Exact steps for others to reproduce the error** To reproduce: 1) Open the attached .blend file. The image texture necessary should be packed inside. 2) Ensure the model has the proper material applied to it, *Material.001*. Its node layout should be an image texture, a custom group node, a Principled BSDF, and a material output from left to right. 3) Ensure the current renderer is set to Cycles. 4) Change the viewport shading mode to *Look Dev*. The stripe on the top of the head and rings on the ears should appear red. 5) Change the renderer to EEVEE. The appearance should remain unchanged. 6) Change the viewport shading mode to *Rendered*. The appearance should remain unchanged. 7) Change the renderer to Cycles. The stripe on the top of the head and rings on the ears will now appear pink (as shown in the original texture) rather than displaying the red color created by the material's node output. [BugRepro.blend](https://archive.blender.org/developer/F7811440/BugRepro.blend)

XanTheDragon commented

2019-10-13 01:04:08 +02:00

Added subscriber: @XanTheDragon

XanTheDragon changed title from ~~Extreme discrepancy between material preview, Cycles, and EEVEE with this node setup~~ to Extreme discrepancy between material preview, Cycles, and EEVEE with specific node setup

2019-10-13 01:04:26 +02:00

XanTheDragon changed title from ~~Extreme discrepancy between material preview, Cycles, and EEVEE with specific node setup~~ to Discrepancy between material preview & render in Cycles and EEVEE with specific node setup

2019-10-13 01:06:55 +02:00

Jacques Lucke commented

2019-10-14 10:25:22 +02:00

Added subscriber: @JacquesLucke

Jacques Lucke commented

2019-10-14 10:25:22 +02:00

The issue could be related to color management, but I'm not sure.

Besides that, I wonder if a simplified node setup like this would work for you as well (the Map Range node only exists in Blender 2.81):

You can also try if the problem still exists when you set the color space to linear. This is not a fix, but might give a hint for what's wrong.

The issue could be related to color management, but I'm not sure. Besides that, I wonder if a simplified node setup like this would work for you as well (the Map Range node only exists in Blender 2.81): ![image.png](https://archive.blender.org/developer/F7815916/image.png) You can also try if the problem still exists when you set the color space to linear. This is not a fix, but might give a hint for what's wrong.

XanTheDragon commented

2019-10-15 05:30:18 +02:00

The setup you gave doesn't work.

There is only one very subtle difference from my original setup as opposed to the one you provided, which is that your setup causes a very slight, almost imperceptible red shift across the entire texture at high thresholds (>0.97) in both Cycles and EEVEE (So at least there's consistency between the two renderers now), and does nothing when at lower threshold values. With the exception of this effect, it has no bearing over the appearance of the texture.

Under both my original setup and your new setup, changing the color space did very little or nothing to the texture, and all changes were not closer to the desired effect.

Update made before post: I did upgrade to 2.81 to make use of the Map node, and I noticed that after reorganizing my node setup so that it had a lot less messy intersecting lines, it has mysteriously started working in Cycles. The only major difference right now is that the "Length" node under the Color Similarity Comparator frame was created because of 2.81's changes to the Cross Product operation under Vector Math (rather than having the "Value" output, it only exports a vector, so Blender added the Length node when upgrading the file to compensate for this change. See attached image).

I spent some great score of time reviewing my previous work and I cannot find any method of reproducing this issue at all in 2.81. Perhaps this is an issue exclusive to 2.80? Seeing that 2.81 has done clear reworks to certain node systems, including one that I made use of (Cross Product), this issue could have been unintentionally resolved with the beta release. I can still get the error to happen in 2.80.

Given that I am unable to cause this issue to occur in 2.81, it may be viable to close this seeing that it has already been resolved in an upcoming build.

The setup you gave doesn't work. There is only one very subtle difference from my original setup as opposed to the one you provided, which is that your setup causes a very slight, almost imperceptible red shift across the entire texture at high thresholds (>0.97) in both Cycles and EEVEE (So at least there's consistency between the two renderers now), and does nothing when at lower threshold values. With the exception of this effect, it has no bearing over the appearance of the texture. Under both my original setup and your new setup, changing the color space did very little or nothing to the texture, and all changes were not closer to the desired effect. **Update made before post:** I did upgrade to 2.81 to make use of the Map node, and I noticed that after reorganizing my node setup so that it had a lot less messy intersecting lines, it has mysteriously started working in Cycles. The only major difference right now is that the "Length" node under the Color Similarity Comparator frame was created because of 2.81's changes to the Cross Product operation under Vector Math (rather than having the "Value" output, it only exports a vector, so Blender added the Length node when upgrading the file to compensate for this change. See attached image). ![image.png](https://archive.blender.org/developer/F7819296/image.png) I spent some great score of time reviewing my previous work and I cannot find any method of reproducing this issue at all in 2.81. Perhaps this is an issue exclusive to 2.80? Seeing that 2.81 has done clear reworks to certain node systems, including one that I made use of (Cross Product), this issue could have been unintentionally resolved with the beta release. I *can* still get the error to happen in 2.80. Given that I am unable to cause this issue to occur in 2.81, it may be viable to close this seeing that it has already been resolved in an upcoming build.

Jacques Lucke commented

2019-10-15 08:16:32 +02:00

Changed status from 'Open' to: 'Archived'

Jacques Lucke closed this issue

2019-10-15 08:16:32 +02:00

Jacques Lucke self-assigned this 2019-10-15 08:16:32 +02:00

Jacques Lucke commented

2019-10-15 08:16:32 +02:00

Closing because it is probably solved in the newest build. Please create a new report, when you find the issue again.

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Discrepancy between material preview & render in Cycles and EEVEE with specific node setup #70775