nodes are darker than node background when both are set to the same value #77293

New Issue

michael campbell · 2020-06-03T07:33:49+02:00

michael campbell commented

2020-06-03 07:33:49 +02:00

System Information
Operating system: Windows-10-10.0.17763-SP0 64 Bits
Graphics card: GeForce GTX 1070/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 442.92

Blender Version
Broken: version: 2.90.0 Alpha, branch: master, commit date: 2020-06-02 22:21, hash: 2e52b3206c
Worked: (newest version of Blender that worked as expected)

Short description of error
nodes are darker than node background when both are set to the same value

Exact steps for others to reproduce the error

**System Information** Operating system: Windows-10-10.0.17763-SP0 64 Bits Graphics card: GeForce GTX 1070/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 442.92 **Blender Version** Broken: version: 2.90.0 Alpha, branch: master, commit date: 2020-06-02 22:21, hash: `2e52b3206c` Worked: (newest version of Blender that worked as expected) **Short description of error** nodes are darker than node background when both are set to the same value **Exact steps for others to reproduce the error** ![image.png](https://archive.blender.org/developer/F8573576/image.png)

michael campbell commented

2020-06-03 07:33:49 +02:00

Added subscriber: @3di

Philipp Oeser commented

2020-06-04 10:15:51 +02:00

Added subscriber: @lichtwerk

Philipp Oeser commented

2020-06-04 10:15:51 +02:00

Changed status from 'Needs Triage' to: 'Confirmed'

Philipp Oeser commented

2020-06-04 10:15:51 +02:00

Can confirm the behavior.
#77340 (Nested frame nodes alpha issue) might be related (in that some alpha layering/blending does unexpected things).

Can confirm the behavior. #77340 (Nested frame nodes alpha issue) might be related (in that some alpha layering/blending does unexpected things).

Julian Eisel commented

2020-06-04 17:52:44 +02:00

Added subscriber: @JulianEisel

Julian Eisel commented

2020-06-04 17:52:44 +02:00

Node backgrounds are drawn with an old trick for anti-aliasing. Unfortunately this trick never ends up providing full opacity. So the background is always slightly transparent and you can see the the node shadow lurking through. One way to fix this would be drawing the background fill without AA, and only draw an outline with AA. That's also what widgets do, but will require corrections to the theme (since the effective color of the node background will change).

Harley Acheson commented

2020-06-04 18:31:04 +02:00

Added subscriber: @Harley

Harley Acheson commented

2020-06-04 18:31:04 +02:00

@JulianEisel - ...drawing the background fill without AA, and only draw an outline with AA...

That can look "okay", but can leave funny artifacts and splotchiness between the outline and the node body. The node background first gets drawn solid with "rounded" corners without AA so they are all blocky at the corner. The outline then drawn smoothly over top, since it is using AA is only itself about 66% opaque, so it doesn't cover those up very well.

So it is a bit of a tossup. How they are now looks nice but you can have trouble getting the exact colors you want. But in most cases you can still get the effect you want even if the color values differ. For them to match exactly they would look a little uglier.

Although I am a bit picky about these things. The timeline "playhead" had to be drawn that way (blue box with current frame) because it had to be full opaque (because it can overlay the other numbers sometime). The issues I am talking about effect that thing's outer edge at its corners. Bothers me to no end, but many people might not notice. LOL

> @JulianEisel - ...drawing the background fill without AA, and only draw an outline with AA... That can look "okay", but can leave funny artifacts and splotchiness between the outline and the node body. The node background first gets drawn solid with "rounded" corners without AA so they are all blocky at the corner. The outline then drawn smoothly over top, since it is using AA is only itself about 66% opaque, so it doesn't cover those up very well. So it is a bit of a tossup. How they are now looks nice but you can have trouble getting the exact colors you want. But in most cases you can still get the effect you want even if the color values differ. For them to match exactly they would look a little uglier. Although I am a bit picky about these things. The timeline "playhead" had to be drawn that way (blue box with current frame) because it had to be full opaque (because it can overlay the other numbers sometime). The issues I am talking about effect that thing's outer edge at its corners. Bothers me to no end, but many people might not notice. LOL

michael campbell commented

2020-06-05 02:38:39 +02:00

I've noticed that the nested frames are the wrong colour even if alpha is set to 1.

All nested frames are the correct colour, but the top level frame is darker, looks to be something to do with the top level frame having a shadow and a highlight at the top.

Could it be that it's actually the shadow causing the issue with the alpha rather than the anti-aliasing when alpha is set to 0?

I've noticed that the nested frames are the wrong colour even if alpha is set to 1. All nested frames are the correct colour, but the top level frame is darker, looks to be something to do with the top level frame having a shadow and a highlight at the top. Could it be that it's actually the shadow causing the issue with the alpha rather than the anti-aliasing when alpha is set to 0? ![image.png](https://archive.blender.org/developer/F8577833/image.png)

Harley Acheson commented

2020-06-05 03:05:16 +02:00

Yes, now that I look at it (LOL), it is just the shadow that is always darkening things.

Although things can always be changed, we'd still need more information on what the real error is. It is true that the node will never completely match the background color exactly, except when background is black of course. But that is (currently) a limitation of the design and implementation, not strictly a bug to correct.

But what is the effect that you wish to achieve? Were you just wanting the same for any arbitrary color? Or white on white? Or transparent on some arbitrary color? Maybe just having control over the shadow opacity would be enough.

If you have a mockup of what you are trying to do just add it to this thread.

Yes, now that I look at it (LOL), it is just the shadow that is always darkening things. Although things can always be changed, we'd still need more information on what the real error is. It is true that the node will never completely match the background color exactly, except when background is black of course. But that is (currently) a limitation of the design and implementation, not strictly a bug to correct. But what is the effect that you wish to achieve? Were you just wanting the same for any arbitrary color? Or white on white? Or transparent on some arbitrary color? Maybe just having control over the shadow opacity would be enough. If you have a mockup of what you are trying to do just add it to this thread.

michael campbell commented

2020-06-05 03:34:32 +02:00

maybe an option to turn off shadows? The aim is to hide the wires by setting the wires to the same colour as the background and frames unless selected. So as soon as I have nodes inside frames the wires become immediately visible because of the colour mismatch.

I'm going to have my first go at making a revision to the blender source in a day or so to make the wires rgba instead of rgb.....well I think i've already made the necessary changes in code, just need to build test and then research how to get it over to the blender gods to see if they'll accept it into master.

maybe an option to turn off shadows? The aim is to hide the wires by setting the wires to the same colour as the background and frames unless selected. So as soon as I have nodes inside frames the wires become immediately visible because of the colour mismatch. I'm going to have my first go at making a revision to the blender source in a day or so to make the wires rgba instead of rgb.....well I think i've already made the necessary changes in code, just need to build test and then research how to get it over to the blender gods to see if they'll accept it into master.

michael campbell commented

2020-06-05 03:39:26 +02:00

I'm also going to try and modify the frame nodes so that they have sockets that can accept multiple wires. I'll need to try and make a new wire type that can plug into the new sockets...they won't transmit data, just for layout purposes like below. Using annotations temporarily, but they're very limited, and cant move if you move the frame node:

then you can show just the wires for the selected nodes, makes it a bit easier to read and less messy:

I'm also going to try and modify the frame nodes so that they have sockets that can accept multiple wires. I'll need to try and make a new wire type that can plug into the new sockets...they won't transmit data, just for layout purposes like below. Using annotations temporarily, but they're very limited, and cant move if you move the frame node: ![image.png](https://archive.blender.org/developer/F8577900/image.png) then you can show just the wires for the selected nodes, makes it a bit easier to read and less messy: ![image.png](https://archive.blender.org/developer/F8577902/image.png)

Pablo Vazquez commented

2021-11-02 15:51:25 +01:00

Added subscriber: @pablovazquez