Terrain images proposal

[mskala at ansuz dot sooke dot bc dot ca]

Here's what I think should happen for terrain images:

* associate with each cell of the map an optional "override" image name
  and x,y coordinate.
* when looking for the image for that cell, first check whether there is
  an override; if so, look in the specified image *at* the specified x,y
  coordinate
* new subform of "area", which takes as input an image name and some x,y
  coordinates specifying a starting point in the image and in the
  map.  When this is specified it overlays the map cells on the image,
  computes the x,y coordinates of each cell in the image, and sets the
  override coordinates accordingly.  The result is that the image appears
  on the map in that region instead of the auto-generated hex grid cells
  that would otherwise appear.  Note that the image has not been processed
  except maybe by being converted to GIF or whatever - it isn't pre-cut
  into hexes and re-arranged.  Note that this subform could be specified
  multiple times, so that you could re-use the same customized image in
  multiple parts of the map and/or only customize an image for part of the
  map while sticking to auto-generation elsewhere.

I think that would be pretty simple to implement and I'm willing to try if
people would like me to.  An issue I forsee is what happens when terrain
changes during a game.  One solution might be to simply blow away the
"override" values as soon as the terrain changes in a cell; then the
designer, if they're going to allow terrain changes while also having a 
custom image map, had better provide default images that will look good 
combined with the custom map.  Another possibility might be to make these
overrides be per terrain type; that mixes badly with per-cell terrain
types, but if we had for each terrain type the ability to specify an
"override map image" then the system could show the appropriate slice of
the large image for each terrain type.
-- 
Matthew Skala
mskala@ansuz.sooke.bc.ca                    Embrace and defend.
http://ansuz.sooke.bc.ca/