Re: [Freeciv-Dev] Hex tileset

[Artur Biesiadowski <abies@xxxxxxxxx>]

trident@xxxxxxxxx wrote:

> The transition doesn't have to be linear alpha blending starting from 50%
> going upto 100%. It could reflect some characteristics of the terrain in
> question: patches of grass for grasslands, alpha blended dunes for deserts,
> rocks for tundra and mountains, etc.


Ok. So let's have images for hexes for which borders extends in all
directions - so it would look more like oval not hex. These borders
would have to be actually pixels copied from other side of hex, so for
uniform terrain they would be blending exactly. Now, when different
terrains are near, nothing has to be done - lower and/or right terrain
will overpaint part of other hex with it's border.

Problem is that some order of paitning is needed. Easiest is upper rows
first, left to right (It gives possibility of 3d feel extending into
upper hexes for free). But this way visual center of single tile of
desert surrounded by grassland will be sligtly displaced - it's borders
will overlay upper and left hexes and it will be overlaid by lower nad
right hexes. Ideally it should be bordered from all sides or extends to
all sides, but I doubt if it is possible to do this in geric manner -
there are too many possible combinations of layout of terrains and
sometimes it is not even clear what behaviour should be, not telling
about implementation.

Mask for "oval hex border" should be same for all terrains I think -
some would use it all, some will leave a bit of land with alfa. It
should not extend too much into neightbour hexes - because then real
center of hex would be too much away from visual one. I think that for
4x4 units hex (flattened) icon should be 5x5, with extra space extending
left and up. Or maybe 6x6 with extra space distributed evenly - it might
be easier to prepare. 

Oceans do not fit here well. Shores need special images, not rocks
extending and alpha blending with water :)
But with overlays, I think that just 6 shore images would be needed - 3
for ocean going into land (from down/right) and 3 for land going into
ocean (left/up). Plus the same for river deltas.

Hex images would be kept somewhere (not in program - on ftp) filling
entire square (5x5 or 6x6 units). Then same mask would be applied to
them all to prepare them to be used by program. This way when mask will
change a bit, regeneration of hexes will be straighforward.
Maybe even such mask could be applied at runtime - it shouldn't be much
work, as it is only alpha channel to add from other source.


Artur