# `MaterialSpec.side`

> Contract 2.0.0 · package sha256 `a857eca95b35921109faf997094bb4192f12527d9d0fcd4be7e97f06425bad6e` · generated from `configurator-runtime.d.ts` by `services/onsite-scripter/scripts/build-contract-docs.mjs`; edit the source, not this file.

Property of [`MaterialSpec`](MaterialSpec.md) · inherited by [`MaterialInput`](MaterialInput.md) · stable · since 2.0.0

```ts
side?: 'front' | 'back' | 'double';
```

Which faces draw: 'front' culls the back faces, as glTF's single-sided; 'double' draws both, for open shells and thin sheets seen from both sides (glTF `doubleSided`); 'back' only the back ones.

**Default:** 'front'

## Generic-API test (spec 3.1)

| Rule | Result |
| --- | --- |
| 1. Neutral name | pass: `side` names no product |
| 2. A precedent | pass: [glTF 2.0 doubleSided](https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#double-sided) (row `G12`); [Unity Material.renderQueue](https://docs.unity3d.com/ScriptReference/Material-renderQueue.html) (row `G12`); [Babylon.js Material.sideOrientation](https://github.com/BabylonJS/Babylon.js/blob/master/packages/dev/core/src/Materials/material.ts) (row `K11`); [glTF 2.0 mesh primitives (indices)](https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#meshes) (row `K4`); [Unity Mesh](https://docs.unity3d.com/ScriptReference/Mesh.html) (row `K4`) |
| 3. Two apps, or labs | pass: 4 apps (ledger: app-378d190f1b, app-b362a81c85, app-fc07850558, app-fc306ec3dc; fleet cross-check: app-fc07850558) |
| 4. The cheaper fix first | decided per need in Appendix B: rows `G12`, `K11`, `K4` at tier labs, stable (a member only where no rule, data, asset or app code serves the need) |