# `Cauldron3D.Billboard`
[🔗](https://github.com/jaman/cauldron/blob/v0.2.2/cauldron_3d/lib/cauldron_3d/billboard.ex#L1)

A flat picture standing in the world, turned to face the camera.

    Cauldron3D.Billboard.polygon(view, {128.0, 0.0, 32.0}, texture, origin: {16, 32})

The picture's pixel `origin` (default its centre) sits at `position`; one pixel is one
world unit times `:scale`. `:upright` (default false) keeps it standing straight up
and only turned about `z`, as a tree or a torch flame is.

# `polygon`

```elixir
@spec polygon(
  Cauldron3D.View.t(),
  Cauldron3D.Vec.t(),
  Cauldron3D.Texture.t(),
  keyword()
) ::
  Cauldron3D.Polygon.t()
```

The picture as a polygon facing `view`. Options: `:origin`, `:scale`, `:upright`,
`:light` (as `{:texture, texture, light}` takes, default `nil`), `:clear` (default 255)
and `:depth`.

---

*Consult [api-reference.md](api-reference.md) for complete listing*