[BUG] Enhanced batching breaks ETF skin-feature render layers under Photon shader (MC 26.1.x) — invisible player skins

[Raconteur32]

Hello !

Human part

First I want to be honest, I found the origin of this problem witht he help of AI. I know that AI reporting can be bullshit, so I will begin with this human part with the facts that I know are 100% true:

Description of the bug

For ETF Skins with emissive features, if the shader photon is applied with and enhanced_batching is activated, the skin will have weird renderings. You can see the screenshots below with what the skin should look like, and what I see when the option is activated:

EDIT: The circular texture is a custoom item placed on the head and is not a mood feature

Environment

• Minecraft 26.1.2 (Fabric Loader 0.19.3)
• ImmediatelyFast 1.15.3+26.1
• Iris 1.11.3+mc26.1.2, Sodium 0.9.1+mc26.1.2
• Shader pack: Photon v1.3b
• Entity Texture Features (ETF) 7.1, Entity Model Features (EMF) 3.2.4

Why an IF report ?

It seems that similar issues with enhanced_batching were fixed in IF side in the past, and the AI interpretation seems to point in this direction. If I'm wrong, I'm apologize.

AI report

Describe the issue

With Photon active on MC 26.1.2, player skins using ETF skin features (emissive / "enchanted" pixels, added via ETF's skin tool) render with the base skin completely invisible — only the emissive overlay pixels are visible, in both first- and third-person view. The rest of the player model (arms, body, head) is transparent.

This affects multiple players on our server.

Test matrix (minimal instance, everything else identical)

ImmediatelyFast	enhanced_batching	Photon shader	Base skin renders?
not installed	—	✅	✅ yes
installed	true	✅	❌ no — only emissive pixels visible
installed	false	✅	✅ yes
installed	true	❌ (shaders disabled)	✅ yes

The bug requires all three: ImmediatelyFast enhanced_batching + Photon + ETF skin-feature skins.

Probable cause

Photon on MC ≥ 26.1 force-enables its separate-entity-draws pipeline (USE_SEPARATE_ENTITY_DRAWS is a hard #define guarded by MC_VERSION >= 260100 in shaders/settings.glsl; translucent entities are composited from a dedicated buffer, cf. blend.gbuffers_entities_translucent.colortex13 = ONE ONE_MINUS_SRC_ALPHA ... and d4_deferred_shading.fsh).

ETF renders skin-feature skins through a custom translucent render layer. With enhanced_batching, the batched draw of that custom translucent layer appears to lose its blend state / ordering when Photon composites it in the deferred pass → the base skin vanishes, while the emissive overlay (rendered through a different path) survives.

Workaround

Set "enhanced_batching": false in config/immediatelyfast.json — fixes the issue completely while keeping ImmediatelyFast's other optimizations.

Similar issues in this repo (already fixed)

Past ETF/EMF conflicts with enhanced batching have been fixed here before by excluding ETF's custom render layers from the batching path — hopefully this can be fixed the same way:

• #412 — Conflict with ETF 7.0.0 on 1.21.1 NeoForge (closed, fixed)
• #454 — Hullbreaker's emissive glow does not work with ImmediatelyFast (closed, fixed)
• #179 — Incompatibility with ETF/EMF and custom entity models (closed, fixed)
• #518 — Render compatibility with Melody's Cute Villagers RP [ETF/EMF] (open, same mod family, no shader involved there)

Related issues (other GitHub repos)

• Photon #539 — armor translucent when using separate entity draws (1.21.11)
• Photon #562 — problem displaying transparent player skin
• Photon #649 — transparency issue with Figura
• ETF #280 — BRIGHTER emissive mode caused transparent pixels on player skin
• ETF #351 — emissive textures only work if Iris is disabled
• ETF #475 — player emissive texture incompatibility with Iris

[Raconteur32]

Examples of affected skins:

[RaphiMC]

Please provide exact steps to reproduce this issue

[Raconteur32]

Steps

1. Create a new 26.1.2 game instance with this list of mods:

• Cloth Config v26.1 [26.1.154]
• Entity Model Features [3.2.4]
• Entity Texture Features [7.1]
• Fabric API [0.155.2+26.1.2]
• Forge Config API Port [26.1.5]
• ImmediatelyFast [1.15.3+26.1]
• Iris [1.11.3+mc26.1.2]
• Mod Menu [18.0.0]
• Placeholder API [3.0.0+26.1]
• Searchables [1.0.2]
• Sodium [0.9.1+mc26.1.2]
• YetAnotherConfigLib [3.9.6+26.1-fabric]

2. Add photon 1.3b to your shaders

3. Put one the skins I gave on your Minecraft account

4. Launch the game and join a word

5. Enable shaders with photon selectioned

6. You should have a rendering problem when you switch to third person view with F5

[RaphiMC]

Is there a way to test this without changing the skin on my account?

[Raconteur32]

Instead of changing your own skin, you can spawn a fake player with my skin in a world where you have command access:

/summon minecraft:mannequin ~ ~ ~ {profile:"Cynrid1"}

I will keep the problematic skin on until you are done testing.

[RaphiMC]

Could not reproduce the issue:

Here is my mod list:

	- cloth-config 26.1.154
	   \-- cloth-basic-math 0.6.1
	- entity_model_features 3.2.4
	- entity_texture_features 7.1
	- fabric-api 0.155.2+26.1.2
	   |-- fabric-api-base 2.0.3+ece063234c
	   |-- fabric-api-lookup-api-v1 2.0.12+d5a053b64c
	   |-- fabric-biome-api-v1 18.0.5+2fa62b4e4c
	   |-- fabric-block-api-v1 3.0.2+ec56b6014c
	   |-- fabric-block-getter-api-v2 2.0.6+ec56b6014c
	   |-- fabric-command-api-v2 3.0.5+e2bdee784c
	   |-- fabric-content-registries-v0 11.3.0+0082c9664c
	   |-- fabric-convention-tags-v2 4.6.2+4f11f7994c
	   |-- fabric-crash-report-info-v1 1.0.3+9f78a5a84c
	   |-- fabric-creative-tab-api-v1 5.0.11+d871b99e4c
	   |-- fabric-data-attachment-api-v1 2.2.9+44a0bd1d4c
	   |-- fabric-data-generation-api-v1 24.3.3+cda368334c
	   |-- fabric-debug-api-v1 1.0.1+c792624d4c
	   |-- fabric-dimensions-v1 5.1.7+ad343a8d4c
	   |-- fabric-entity-events-v1 5.0.2+e2bdee784c
	   |-- fabric-events-interaction-v0 5.2.2+07b380be4c
	   |-- fabric-game-rule-api-v1 4.0.5+d871b99e4c
	   |-- fabric-item-api-v1 14.3.0+6d1aaa724c
	   |-- fabric-key-mapping-api-v1 2.0.4+e2bdee784c
	   |-- fabric-lifecycle-events-v1 4.1.1+df84eb3d4c
	   |-- fabric-loot-api-v3 3.0.12+00a1fba64c
	   |-- fabric-menu-api-v1 2.0.14+d871b99e4c
	   |-- fabric-message-api-v1 7.0.5+dae8ce3e4c
	   |-- fabric-model-loading-api-v1 8.0.11+c80601bb4c
	   |-- fabric-networking-api-v1 6.3.1+554860db4c
	   |-- fabric-object-builder-api-v1 23.1.0+abb459f14c
	   |-- fabric-particles-v1 5.0.15+b61fef434c
	   |-- fabric-permission-api-v1 1.0.2+7437387b4c
	   |-- fabric-recipe-api-v1 9.0.16+be4b75ae4c
	   |-- fabric-registry-sync-v0 7.1.0+2fa62b4e4c
	   |-- fabric-renderer-api-v1 13.0.8+c80601bb4c
	   |-- fabric-renderer-indigo 8.1.5+1403e82c4c
	   |-- fabric-rendering-fluids-v1 6.0.1+d871b99e4c
	   |-- fabric-rendering-v1 23.3.1+e9207d814c
	   |-- fabric-resource-conditions-api-v1 6.1.0+83dd0ba34c
	   |-- fabric-resource-loader-v0 3.3.17+4fc5413f4c
	   |-- fabric-resource-loader-v1 2.0.10+7c44c7324c
	   |-- fabric-screen-api-v1 5.1.0+981dd9b24c
	   |-- fabric-serialization-api-v1 2.0.3+11a26f314c
	   |-- fabric-sound-api-v1 2.0.4+11a26f314c
	   |-- fabric-tag-api-v1 2.1.1+371cf5db4c
	   |-- fabric-transfer-api-v1 8.0.6+357ea7334c
	   \-- fabric-transitive-access-wideners-v1 8.1.3+3ff549fb4c
	- fabricloader 0.19.5
	- forgeconfigapiport 26.1.5
	   |-- com_electronwill_night-config_core 3.8.3
	   \-- com_electronwill_night-config_toml 3.8.3
	- immediatelyfast 1.15.4-SNAPSHOT+26.1
	- iris 1.11.3+mc26.1.2
	   |-- fabric-api-base 2.0.3+ece063234c
	   |-- io_github_douira_glsl-transformer 3.0.0-pre3
	   |-- org_anarres_jcpp 1.4.14
	   \-- org_antlr_antlr4-runtime 4.13.1
	- java 25
	- minecraft 26.1.2
	- mixinextras 0.5.5
	- sodium 0.9.1+mc26.1.2
	   \-- fabric-api-base 2.0.3+ece063234c
	- yet_another_config_lib_v3 3.9.6+26.1-fabric
	   |-- com_twelvemonkeys_common_common-image 3.12.0
	   |-- com_twelvemonkeys_common_common-io 3.12.0
	   |-- com_twelvemonkeys_common_common-lang 3.12.0
	   |-- com_twelvemonkeys_imageio_imageio-core 3.12.0
	   |-- com_twelvemonkeys_imageio_imageio-metadata 3.12.0
	   |-- com_twelvemonkeys_imageio_imageio-webp 3.12.0
	   |-- org_quiltmc_parsers_gson 0.2.1
	   \-- org_quiltmc_parsers_json 0.2.1

I am also using the photon_v1.3b shader and default ImmediatelyFast config

[Raconteur32]

You said that you have the default config for IF, can you confirm that you have the default config for EMF and ETF as well ? Can you see the glowing / enchanted pixels on the skin ? (the blue ones)

If yes, I will try to find more informations about what could trigger the bug. Maybe it's hardware specific.

EDIT: I tested with your exact mod list again and with default config for all mods, and I still have the problem. The only thing I can't match in your test is your version of IF: 1.15.4-SNAPSHOT+26.1

Could you have any change in your local version that could resolve this kind of bug ? Could you test with 1.15.3+26.1 out of the dev env to confirm the harware problem theory ?

[RaphiMC]

I created a new prism instance with only the mods previously mentioned installed (And ImmediatelyFast 1.15.3) and I still couldn't reproduce it (Or is the bug already visible in that image and I didn't see it?)

[Raconteur32]

Seems to be fixed with the last version off EMF and ETF

I will confirm and come back when I'm 100% sure