[Pgfplots-features] Centered color bars

[Philipp A. <fly...@we...>]

hi,

i have a picture that uses a diverging color map.

but minimum and maximum don’t have the same absolute value (but -0.2 and
+0.5 instead)

i want to be able to do a centered color map, where “0” is the middle
color, all points >0 use the upper half of the map, and all <0 the lower
half.

the color bar should be skewed according to the real values (i.e. the lower
half of the map should take up 2/7 of the bar,a nd the upper half the
remaining 5/7)

maybe a point meta center=[auto,<scalar>] key, with auto meaning a
calculated value of (point meta max + point meta min) ÷ 2

best,

philipp