use Makie.automatic in lighting docs

MakieCore/src/basic_plots.jl

@@ -79,7 +79,7 @@ end
 """
 ### 3D shading attributes
 
-- `shading = automatic` sets the lighting algorithm used. Options are `NoShading` (no lighting), `FastShading` (AmbientLight + PointLight) or `MultiLightShading` (Multiple lights, GLMakie only). Note that this does not affect RPRMakie.
+- `shading = Makie.automatic` sets the lighting algorithm used. Options are `NoShading` (no lighting), `FastShading` (AmbientLight + PointLight) or `MultiLightShading` (Multiple lights, GLMakie only). Note that this does not affect RPRMakie.
 - `diffuse::Vec3f = Vec3f(1.0)` sets how strongly the red, green and blue channel react to diffuse (scattered) light.
 - `specular::Vec3f = Vec3f(0.4)` sets how strongly the object reflects light in the red, green and blue channels.
 - `shininess::Real = 32.0` sets how sharp the reflection is.

docs/reference/scene/lighting.md

@@ -34,6 +34,7 @@ The possible options for `shading` are:
 - `shading = NoShading` disables light calculations, resulting in the plain color of an object being shown.
 - `shading = FastShading` enables a simplified lighting model which only allows for one `AmbientLight` and one `DirectionalLight`.
 - `shading = MultiLightShading` is a GLMakie exclusive option which enables multiple light sources (as set in the `ScreenConfig`, default up to 64) as well as `PointLight` and `SpotLight`.
+- `shading = Makie.automatic` derive one of the above options based on the lights in `scene.lights`
 
 !!! note
     You can access the underlying scene of an `Axis3` with `ax.scene`.

src/lighting.jl

@@ -240,7 +240,7 @@ function default_shading!(plot, lights::Vector{<: AbstractLight})
         else
             shading = automatic
         end
-        @warn "`shading = $prev` is not valid. Use `automatic`, `NoShading`, `FastShading` or `MultiLightShading`. Defaulting to `$shading`."
+        @warn "`shading = $prev` is not valid. Use `Makie.automatic`, `NoShading`, `FastShading` or `MultiLightShading`. Defaulting to `$shading`."
     end
 
     # automatic conversion