Large image files load to black texture about notan

[Quackdoc]

commenting here since I was not clear. the patch is used to allow notan to load the image directly. it doesn't fix the bug.

[Nazariglez]

Hello, thanks for the heads up, I'll take a look and come back soon!

[Nazariglez]

Well, your investigation at woelper/oculante#152 saved me a lot of time, thanks!

I did some changes (here) to allow loading any image no matter the size. And the issue we have with large texture is 99% because the texture is bigger than allowed by OpenGL. I added a warning to inform this. Although I am not sure how to manage this. There are some options:

• Leave a warning, allowing to load the image even if it's displayed as a black rectangle.
• Return an error when creating the texture. Forcing the dev to manage the error or panic.

My main worry is that this is not something that we can know at compilation time, with that kind of issue I am always prone to panic fast in debug mode. However this case depends on the user's hardware, a panic can be the worst for the user, and a warning log can be insufficient for the app's dev.

We can go for now with the warning (for 0.9.5) and change the behavior for 0.10.0, but I don't know what will be a good solution, to be honest...

Any thoughts?

[Quackdoc]

I think returning an error should be the appropriate solution. It would be best to let the application handle the error, this works well since a potential solution for this would be to tile textures until you have enough space to work with. returning the max size is certainly useful for this

[woelper]

I also think an error would be best. In a game, I'd be forced to care about the texture and make sure it has the correct size. In Oculante's case we could either pass the error up or even decide to resize the texture on the fly and display a message.

[Nazariglez]

It makes sense, I am doing the change and 0.9.5 will be out this week. Thanks!

[woelper]

Amazing, thank you so much! I will build a release for oculante afterwards, lots of other good things in 0.9.5, too!

[woelper]

I did some more investigation, and at least on my system the texture limit is 16384x16384px. Is there any way in notan I can get the maximum supported texture size before loading fails? I am thinking of creating multiple textures or resizing the texture to fit before attempting to display it.

[riverfr0zen]

Is the info returned by Graphics::limits() reliable for this?
https://docs.rs/notan/latest/notan/app/struct.Graphics.html#method.limits

[woelper]

Thanks @riverfr0zen - I should have read the docs more thoroughly. This does exactly what I want and - at least in my case - returns the same value. I'll use that!

[Nazariglez]

Is the info returned by Graphics::limits() reliable for this? https://docs.rs/notan/latest/notan/app/struct.Graphics.html#method.limits

Yep, this is the value returned by the GL driver. Should be reliable.

[Nazariglez]

This should be done with the latest version on crates.io and the main branch, let me know otherwise, thanks for the help!

[woelper]

Thanks!