Colour by depth in HEAD: survey viewing blues.

[John P N Pybus]

Hi Olly,

I've built the pre-1.0.26 code from CVS head.  I like the new depth 
gradient in aven!  However the tones are considerably darker than the 
previous version.  The oranges/yellows are ok, but the blue is now 
pretty hard to see against the black background.

I think that ideally a gradient which is uniformly bright (in a 
perceptual sense) should be chosen.  For extra points it should be 
linear in perceived colour difference.  At the very least, can we 
brighten up those blues a little though?

On an unrelated note, I noticed screen shots of a colour by year 
version. I'd currently like to produce colour by survey grade.  No doubt 
I'll find a way to hack it in as is, but have you thought of creating 
general 'stylesheets' which could be used to specify all of the viewing 
parameters (and let you choose any depth gradient you fancy, of course)?

Yours,

John