Documentation Talk:Reference Section 5

The section on image_map should reference function images...

IMAGE_MAP:
  image_map {
    FUNCTION_IMAGE | [BITMAP_TYPE] "bitmap[.ext]"
      [IMAGE_MAP_MODS...]
  }
FUNCTION_IMAGE:
  function I_WIDTH, I_HEIGHT { FUNCTION_IMAGE_BODY }
FUNCTION_IMAGE_BODY: 
  PIGMENT | FN_FLOAT | pattern { PATTERN [PATTERN_MODIFIERS] } 
BITMAP_TYPE:
  gif | tga | iff | ppm | pgm | png | jpeg | tiff | sys
IMAGE_MAP_MOD:
  map_type Type | once | interpolate Type | 
  filter Palette, Amount | filter all Amount |
  transmit Palette, Amount | transmit all Amount

For syntax of function images see "Function Image".

After the optional BITMAP_TYPE keyword is a string expression ... etc.