L16 images render as black until edit panel is open

[woelper]

Describe the bug
I suspect there is an issue with the texture / display of L16 images. It works if the edit panel is open and a Rgba8 operator is automatically added.

Tagging @B-LechCode for visibility.

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[B-LechCode]

Do you know the min and max pixel values in your L16 images?
I suppose the values are just too low?

[woelper]

Oh, that could be a possibility. I am testing Dicom support and they could be out of visual range. I am not sure, but even if that was the case I don't know if converting them to rgba8 would compress them into 8bit per channel so they become visible - not sure if image is doing anything along those lines. I can check that!

[B-LechCode]

Okay, I checked it up:
Using the edit panel sets the data type to 8 bit - that's why it works. As a workaround: change it to rgba32f if you need more dynamic range.
Using 16 Bit data with values up to 2^16-1 always results in a black rendering.

Will look more deeply into in the evening.

I think it's linked to the texture type. R16 is missing, so I used R16Uint

I suggest a 2 level fix:

1. Convert 16 Bit types to float in texture wrapper - we know that float is working fine (short term fix, will do it by this evening so you can carry on with dicom)
2. Add R16 type to notan and bring up a pull request to them (long term fix to save memory and cpu cycles)

I'm still kinda a newbie to rust. Is there an option to clone notan from github and use that source code directly to compile oculante with it? So I would have a good setup to test everything together :)

[B-LechCode]

@woelper created the fix: #616

[woelper]

Thank you so much!
I had one change request as this seems to change a CI file. If possible we could use a different texture format, but I would also be fine with float first and then do a proper fix later.

[B-LechCode]

Thank you so much! I had one change request as this seems to change a CI file. If possible we could use a different texture format, but I would also be fine with float first and then do a proper fix later.

You're welcome!

I'm still kinda a newbie to rust. Is there an option to clone notan from github and use that source code directly to compile oculante with it? So I would have a good setup to test everything together :)

Do you maybe have some hints for me? :)

[Stoppedpuma]

I'm still kinda a newbie to rust. Is there an option to clone notan from github and use that source code directly to compile oculante with it? So I would have a good setup to test everything together :)

Do you maybe have some hints for me? :)

We were actually just discussing this the other day as Notan is behind in egui version which seems to be a bit of an annoyance. I emailed the dev a day or two ago asking about the status of updates in Notan since the entire repo seems to be quite inactive since around September. I will get back to you as well on this if I get a response!

[Stoppedpuma]

@B-LechCode Good news! Notan is still actively being developed, the creator is just focusing on some other things at the moment. If you had a PR in mind on Notans side, it should be fine to do so!