Incorporating the availability of screen and depth textures for the GLES3 backend

[the-brickster]

The PR is for the implementation of SCREEN_TEXTURE and DEPTH_TEXTURE for the GLES3 backend.

The link for the testbed for this PR can be found here: https://github.com/the-brickster/Godot4Testbed/tree/master

[BastiaanOlij]

Generally looks good, just need to remove the changes to the build files and undo the break in projection matrix values.

If multiview could be taken along that would be a bonus, but we can add that later as well.

[BastiaanOlij]

cc @clayjohn @dsnopek

[akien-mga]

This seems to go directly against #70967...?

[BastiaanOlij]

This seems to go directly against #70967...?

Ah I overlooked that, most of this PR is still valid but it indeed reintroduces the renames.

So yeah, @the-brickster we don't need to re-add actions.renames["SCREEN_TEXTURE"] and related things. There is a new way of doing this by adding a uniform with a hint in your shader.

So in your test project, in your shader simply add:

uniform sampler2D my_screen_texture : hint_screen_texture; 

Have a look at how things have changed in the Vulkan renderer if you're not sure. The PR Akien mentions should provide you all the further background.

[the-brickster]

Ahh ok, so that's why I needed to change it in my test project. I will get the required changes within the next day.

[the-brickster]

This seems to go directly against #70967...?

I have integrated those changes into my PR

[Riteo]

@the-brickster I don't get it... How can this PR be "fixed" if the whole concept of SCREEN_TEXTURE and DEPTH_TEXTURE has been scrapped in #70967?

[the-brickster]

@the-brickster I don't get it... How can this PR be "fixed" if the whole concept of SCREEN_TEXTURE and DEPTH_TEXTURE has been scrapped in #70967?

It hasn't been scrapped per se, it's just been replaced in favor of using hint_depth_texture and hint_screen_texture, you can confirm this by using the following test project I use:
https://github.com/the-brickster/Godot4Testbed/tree/master
Within the scene splat_test.tscn

[aaronfranke]

@the-brickster To avoid confusion, you can edit the title and description of the PR. It would also be a good idea to include a link to the test project you're using in the PR description.

[Riteo]

@the-brickster

It hasn't been scrapped per se, it's just been replaced in favor of using hint_depth_texture and hint_screen_texture

Oh all right. Makes sense then. I'd change the title like aaron proposed since otherwise things get pretty confusing.

[the-brickster]

@aaronfranke @Riteo title changed and testbed project added

[clayjohn]

Running the code locally did not work with this current version. I had to make some changes myself to get it working. I have added those changes as suggestions.

Once those changes are applied and this PR is rebased it should be ready to go (and can be merged shortly after we release Godot 4.0).

[the-brickster]

@clayjohn changes pushed and rebased against master

[clayjohn]

This looks good to go now. We can go ahead and merge it shortly after releasing 4.0 with an aim to get it into 4.1 and perhaps cherry pick to 4.0.1

[YuriSizov]

Thanks! And congrats on your first merged pull request, I think! Ah, I was mistaken. But still, great work :)

[YuriSizov]

Cherry-picked for 4.0.2.