Tilecache and Aerial Layers

When generating a TileCache for Aerial layers where there are regions without Aerial Photo Data, in addition to the Layer for the Aerial Photography itself, an additional layer needs to be set up to cover the blank/empty regions (built in a similar way to creating OutOfArea masks - i.e. subtracting the Aerial data from a polygon covering the whole region).

See below for an example:

LAYER
# WMS vvvvvvv      
  METADATA
    WMS_TITLE "Council @ NO aerial"      
  END
# WMS ^^^^^^^
  NAME "NoAerial"
  GROUP "aerial"
  STATUS DEFAULT
  DATA "Base/Aerialphotos/no_aerial.shp"
  LABELITEM "ID"
  TYPE POLYGON
  CLASS
     STYLE
      COLOR 200 200 200
      OUTLINECOLOR 0 128 0
     END
   LABEL
      FONT "arial"
      TYPE TRUETYPE
      ANTIALIAS TRUE
      COLOR 0 0 0
      OUTLINECOLOR 230 230 230
      SIZE 10
      POSITION AUTO
      FORCE TRUE
      PARTIALS FALSE
      WRAP "¬"
   END   
   TEXT "Sorry...¬No Aerial¬Photography¬Available..."
  END
END

The WRAP parameter needs to be in the LABEL node - using a character that is NOT likely to be used elsewhere.

The TEXT parameter needs to be in the main CLASS node - and be formatted using the selected WRAP char (in this example, the char “¬”)

An alternative approach could be to define the custom text in an image/symbol that can then be tiled across the polygon.