Merge branch 'spatial_start' of https://github.com/teunbrand/ggsql into spatial_start

Author: teunbrand

doc/syntax/layer/type/spatial.qmd

@@ -5,7 +5,7 @@ title: "Spatial"
 > Layers are declared with the [`DRAW` clause](../../clause/draw.qmd). Read the documentation for this clause for a thorough description of how to use it.
 
 The spatial layer is used to render geographic geometries consisting of polygons, lines and points used to make maps like choropleths.
-It differs from other layers in that uses a special [simple features](https://en.wikipedia.org/wiki/Simple_Features) geometry column that defines the shapes.
+It differs from other layers in that it uses a special [simple features](https://en.wikipedia.org/wiki/Simple_Features) geometry column that defines the shapes.
 
 ## Aesthetics
 The following aesthetics are recognised by the spatial layer.
@@ -48,37 +48,39 @@ Note that the geometry column is automatically detected.
 
 ```{ggsql}
 VISUALISE FROM ggsql:world
-  DRAW spatial
+DRAW spatial
 ```
 
 If the geometry column isn't automatically detected —for example because it has a non-standard name— you may need to declare the mapping explicitly.
 
 ```{ggsql}
 SELECT geom AS foo FROM ggsql:world
 VISUALISE
-  DRAW spatial MAPPING foo AS geometry
+DRAW spatial 
+  MAPPING foo AS geometry
 ```
 
 Filtering on other columns.
 
 ```{ggsql}
 VISUALISE FROM ggsql:world
-  DRAW spatial FILTER continent == 'Asia'
+DRAW spatial 
+  FILTER continent == 'Asia'
 ```
 
 Filtering based on spatial operations.
 
 ```{ggsql}
 VISUALISE FROM ggsql:world
-  DRAW spatial 
-  FILTER ST_Intersects(geom, ST_MAkeEnvelope(-20.0, -35.0, 55.0, 38.0))
+DRAW spatial 
+  FILTER ST_Intersects(geom, ST_MakeEnvelope(-20.0, -35.0, 55.0, 38.0))
 ```
 
 Make a choropleth map by mapping a variable to a fill aesthetic.
 
 ```{ggsql}
 VISUALISE FROM ggsql:world
-  DRAW spatial 
-    MAPPING population AS fill
-    SETTING opacity => 1
+DRAW spatial 
+  MAPPING population AS fill
+  SETTING opacity => 1
 ```