What happened?

AF breaks in Complementary shaders when not on vanilla textures. I reported this to Emin but I suspect it might be an Iris (or sodium) issue for 2 reasons

1. The issue isn't present on optifine/optifabric
2. Once triggered the issue will persist even after removing the texture pack and reloading the shader. I don't think a shader can "remember" the texture pack so it must be something outside the shader that's broken like the texture atlas or something.

The issue manifests in 3 ways. (Ik it's not actually separate issues but I'm separating it into different symptoms for fun)

1. Artifacts appear on fire/soul fire. Most visible on right angles or very close to them (ie. 0 0 0 90 90 0 -90 0 180 0)
2. Artifacts appear on most blocks. Same condition as above except you also have to be a very specific distance away from the block (only on the axis you're facing).
3. You see weird noise when standing right next to a block. Most visible on fire. You don't need to be facing a right angle for this one.

One notable thing is that no. 3 gets worse depending on the frame of the fire texture. Makes me suspect its related to the color of the pixels? Also the artifacts from no. 2 look different depending on the texture and don't appear on some blocks at all. For example all concrete colors aren't affected but all wool colors are affected.

Reproduction Steps

• Remove your options.txt (just to get rid of any other texture packs, or other differences which might make reproduction harder)
• Remove every mod but iris and sodium from your mods folder
• Turn on texture filtering in the performance tab of Complementary 5.2.2
• Load Vanilla Tweaks in the provided configuration: Selected Packs.txt

Then in a world

• Place a fire somewhere
• Crouch and look at the fire. Move your camera and walk around till you see it. (You will see issue no. 3)
• Run command /tp @p ~ ~ ~ 0 0 (You will see issue no. 1)

To observe issue no.2

• Create a Debug World
• Set your FOV to 90 and FOV effects to 15%
• Disable waving effects (otherwise you won't see it on leaves)
• Run command /execute in minecraft:overworld run tp @s ~ y_value ~ 0.00 90.00 (this is quite inconsistent. Here's a few Y values that worked for me 73.495 73.497 73.511 73.5137 73.513)
• You will now be able to see the issue on most blocks.

Since issue no.2 is quite inconsistent to reproduce here's some other steps which might yeild it. (or just run /tp @p ~ ~ ~ 0 0 and fly foward and backwards in a world till you see it)

Hyper Specific Reproduction Steps

• Set your FOV to 90
• Set FOV effects to 15%
• Create a void superflat world
• Run these commands /execute in minecraft:overworld run tp @s 1035.70 77.00 -194.338 0.00 0.00 /fill 1023 70 -192 1045 85 -192 minecraft:grass_block /effect give @p minecraft:slowness infinite 5 true
• You will observe the textures break

After doing the steps above you can also do

• Run commands /setblock 1035 76 -195 minecraft:stone /execute in minecraft:overworld run tp @s 1035.70 77.00 -194.3715 0.00 0.00
• Crouch to exit fly mode (cuz it changes your FOV)
• You will observe the textures break

Screenshots

Examples of the issues

No.1

No. 2

No. 1 & 2 at the same time

No. 3

Minecraft Version

1.21

Iris Version

1.7.3

Operating System

Windows 10

What is your GPU?

GTX 1060 6GB

Additional Context

Link to the thread in Emins server: https://discord.com/channels/744189556768636941/1262903359304896532/1262903359304896532

I can now reproduce the issue on optifine (not sure why I couldn't before) so it's def not an iris issue