OpenGL: ReflectionProbe is not reimplemented yet

[Lasuch69]

Tested versions

Godot v4.2.1.stable

System information

Fedora Linux 38.20231205.0 (Silverblue) - Wayland - GLES3 (Compatibility) - AMD Radeon RX 550 / 550 Series (polaris12, LLVM 16.0.6, DRM 3.54, 6.6.3-100.fc38.x86_64) () - AMD Ryzen 5 3400G with Radeon Vega Graphics (8 Threads)

Issue description

Reflection Probe makes a huge difference in fidelity at a really low cost, which makes it a good choice for mobile games.

However Reflection Probe is still missing in Compatibility backend.

Compatibility backend:

Mobile backend:

Steps to reproduce

Create Reflection Probe while using Compatibility backend to see that nothing happens. Which isn't the case with backends using RenderingDevice (Mobile and Forward+).

Minimal reproduction project (MRP)

N/A

[Lasuch69]

Started working on this.

Edit: This doesn't look like an easy task at all lol

[Lasuch69]

Just a quick update.

I feel like I am so close to having anything rendered into the reflection probe, however I am not sure how to deal with render targets and framebuffers yet. I am literally learning OpenGL as I go.

Now I need to figure out how to render to the texture. This is fun! :)

[daustria]

how is this going? Feel free to share some of the implementation details, either here or maybe DMs on the contributors chat. i am really interested the implementation of this but seems overwhelming with my background, i hardly know where to start.

[Lasuch69]

how is this going? Feel free to share some of the implementation details, either here or maybe DMs on the contributors chat. i am really interested the implementation of this but seems overwhelming with my background, i hardly know where to start.

I feel lost at shaders and atlases.

[daustria]

that's okay! it took me a long time to get comfortable with even the basics of opengl, and im still new to graphics and dev work in general. youve been learning it on the fly for a couple of weeks or less, and brave enough to take on such a task. so i think youre doing great. i hope you can stay motivated, seek help where you can, and do what you need to do, whether you decide to put this task on the backburner or keep at it.

[Lasuch69]

Now that I know how to bind data to a scene shader, sending the data into it is my main priority. However atlases are still the biggest problem for me lmao.

Learning Vulkan first was the best thing I could've done! :)

[Lasuch69]

Giving up on it for now. I will try to understand Godot's shader pre-processing, if I do then I will work on it further and give an update.