Create: Backtank Trims & Dyes

A small standalone NeoForge mod for Create's diving gear. It does two things:

Armor trims — re-enables smithing-table trims on Create's diving helmets, diving boots and backtanks, and makes them render on the worn equipment.
Dyeable visors — lets you recolour the eye-visor of the diving helmets, with an optional slow pulsing effect.

I got annoyed after Create issue #6213 never got fixed, and just did it myself.

Armor trims

The problem

Create's copper/netherite diving helmets, diving boots and backtanks are armor, but Create explicitly opts them out of the minecraft:trimmable_armor tag. As a result:

the smithing table refuses to trim them, and
even if a trim is forced onto them (applied before conversion, NBT editors, Almost Unified, …), the trim never renders.

What the mod does

Re-enables trimming for all six pieces by re-adding them to the trimmable_armor tag. The mod loads after Create, so this addition wins over Create's removal.
Renders the trim on the netherite backtank. The five other pieces render through vanilla's armor layer, so their trims appear automatically once trimmable. The netherite backtank is drawn by Create's own custom renderer, which skips the vanilla trim pass — so the mod adds a dedicated render layer that draws the trim decal over the diving suit.
Adds inventory trim icons for the four flat diving items (helmets and boots), so a trimmed piece shows its trim overlay in inventories and tooltips.

Item Smithing table Worn trim Inventory icon Copper / Netherite Diving Helmet ✅ ✅ ✅ Copper / Netherite Diving Boots ✅ ✅ ✅ Backtanks ✅ ✅ ⚠️

⚠️ The backtank's inventory icon does not show a trim overlay — backtanks use a 3D block model, which vanilla's flat trim-overlay system cannot decorate. The trim still renders correctly on the worn backtank.

Dyeable visors

The copper and netherite diving helmets have a coloured band (a "visor") around the eyes. This mod lets you recolour just that visor, leaving the metal of the helmet untouched.

Dye it like leather armor: put a diving helmet and any dye(s) together in a crafting grid. Mix several dyes for blended colours.
Make it pulse by crafting a dyed helmet together with an amethyst shard. The visor then slowly breathes through lighter and darker shades of its colour, and a Pulsating line appears in the tooltip.
Wash it clean by right-clicking a water cauldron while holding the helmet. That removes the dye and the pulse.

Dyeing affects the worn helmet's visor only; the flat inventory sprite is unchanged.