Re: Terrain images proposal

[mskala@ansuz.sooke.bc.ca]

On Sun, 26 Sep 2004, Eric McDonald wrote:
> Another issue is "z-ordering". You would probably have to provide some 
> mechanism so that the order in which redraws were stacked could be 
> determined (not only can regular hexes and embedded images overlap with 
> one another, but multiple embedded images can overlap with one another 
> as well).

What I had in mind was that each cell has only one override image, if any,
and if it has one, that completely replaces the regular terrain image.  So
when XConq wants to draw the cell terrain in a cell, at present it looks
up the cell's terrain type and then looks up the image for that terrain
type.  With my change, it would look for the image for that terrain type
and that cell position; if there was one, it would use that, otherwise it
would use the default image for that terrain type.  If you attempt to
define more than one override image for a cell position, that's either a
syntax error, or the last one you define overwrites any previous
one.  Stacking order is never an issue - there is only one in the stack.
It does become an issue for aux terrain, but it always was.

If you attempt to define an override image for a cell that is "normal"
terrain, that's fine, no problem, then it stops being "normal" terrain.  
If you tell XConq you are defining an override image for a given cell but
the image you specify doesn't cover the cell, then (depending on
implementation) that's either a syntax error, or it fills in the extra
space with black or some other well-defined pattern, or it's undefined,
and in any case, the solution is not to do that if you don't like the
result.

A critical point here is that the entire rectangle in the image would not
necessarily appear on the map.  When you tell XConq "take this cell out of
this image" then that cell becomes a hexagonal window into the image, so
unless you do that with a cell that goes over the edge of the image (and
normally you wouldn't), you don't see the edge of the image.  That's not
so unusual, because it's the way that terrain images already work; you
specify a recantangle in an image, but only the hex shape is actually
visible.
-- 
Matthew Skala
mskala@ansuz.sooke.bc.ca                    Embrace and defend.
http://ansuz.sooke.bc.ca/