[Therion] Wishlist - colouring control improvements

[Stacho Mudrak]

Wookey wrote:
> Colour scrap by altitude is nice but the abrubt joins can look nasty in the
> middle of wide, nominally horizontal passage.  It works really well in the
> 'soundriver' area where there are nicely-merging shades of green, but
> nastily in other some other areas. Some way to graduate the join a bit would
> make it look a lot nicer. Or apply more detailed colour control to a scrap
> like 'nearly the same as neighbour scrapname'.

This I have to discuss with MartinB. As far as I know PDF - some 
gradient colorings are possible, but only for triangles. Not for bezier 
curves. So in principle, there are two possibilities:

1. Triangulate the outline = huge problem of contrained Delaunay 
triangulation. All algorithms I have are GNU incompatible, or parts of 
huge non-standard libraries or both :).

In any case - triangulation is also important for 3D (current algorith 
fails at some cases, especially on non Intel processors :) so this 
problem must be solved somehow in the future. We will probably leave GPL 
and come to some other license type (I prefer no licensing at all :)

> Also my users have complained that the colours are 'too random and garish'
> and I am inclined to agree. They like the depth colouring in Aven, so could
> we try to use the same gradient colours? 
> 
> Probably what is really needed is a way to specify the colour set/gradient,
> and proably a way to specify it for individula scraps too. Perhaps I already
> can?

No, it is in TODO only. When I will fix the bugs, I can start working on 
it. It should be no problem. User must be able to define own colors for 
altitudes, maps, surveys, dates and use multiple color gradients (aven 
like for example). It is in TODO, but nobody was asking for this and my 
main problem is 3D.

> I think the colouring is a major step forward, but some more detailed
> control is needed. There are a lot of ways this could be done and input for
> others is welcome.

Yes. 100% agree. I will put it higher priority.

> Also having blue water would make a lot of sense for water areas, streamflow
> arrows etc. 

This you can do by redefinition of symbols. See "Rabbit-cave" example - 
extended elevation. There the water should be blue. Simmilar way you can 
redefine colors of other symbols in layout.

S.