A trim is a greyscale stencil and a palette swap, not a coloured texture
Armour trims look like 198 separate textures. They are not. The game ships one greyscale image per pattern per armour layer, and recolours it at runtime using an eight-pixel palette belonging to the material. Understanding that split explains almost every question people have about trims.
Two files, two jobs
A finished trim needs exactly two things, and they never touch each other:
| Part | What it is | What it controls |
|---|---|---|
| Pattern | Greyscale PNG, one per armour layer | Shape and placement |
| Material | An 8-pixel palette strip | Colour only |
The pattern texture uses eight shades of grey. Each shade is an index. At render time the game reads the index and looks up the colour at that position in the material palette. Grey level 0 becomes palette colour 0, grey level 7 becomes palette colour 7.
Why every combination works
Because the pattern never stores a colour, there is nothing to clash. Any of the 18 patterns composes with any of the 11 materials, and the game does not need a texture for each pairing — it needs 18 patterns plus 11 palettes, not 198 images. Add a nineteenth pattern and it works with all eleven materials on the day it ships, with no extra art.
That is also why a trim can never change the outline of a piece. The stencil is drawn inside the armour texture’s own bounds; there is no geometry involved, no extra model, no thickness. A netherite chestplate with a Silence trim occupies exactly the same pixels as one without.
The darker-armour rule
One palette is not enough. A gold trim on iron armour and the same gold trim on gold armour would vanish into the base metal, so each material carries a second palette used when the trim material matches the armour material. It is the same eight indices pointing at a darker set of colours, which is why a gold-on-gold trim reads as an engraved line rather than an applied stripe.
This is a lookup swap, not a blend. There is no opacity, no multiply, no tint maths in between — which is why trims stay crisp at every resolution and why a resource pack can replace a palette with eight arbitrary colours and get a clean result.
What this means when you are building a look
- Judge the pattern first, in one material. The shape is the decision; colour is a second, independent pass. Rerolling both at once is how people end up scrolling forever.
- Check it on the armour you will actually wear. The darker-armour rule means a pairing you liked on diamond can read completely differently on netherite.
- Look at all four pieces together. Patterns are cut per layer; a motif that dominates the chestplate may be a single stripe on the boots.
The 3D viewer exists for exactly this: it applies the real palette swap on a real player model, so what you see is what the game renders — not an approximation drawn in a flat preview.