locationtech
Add InterpolatedColorMap
There are currently some very good tools for computing breaks and interpolating colors but these facilities are relatively low level and primarily exercised either by rendering via ColorMap, which explicitly maps values to colors and establishes some rules for deciding what happens above and below the explicitly provided break, or by rendering via ColorRamp, which computes a histogram, and associates the provided ramp with colors such that more colors are distributed over the densest regions in the value-space as represented by the histogram. These are both useful, high level ways to specify rendering behavior but they are by no means sufficient to some common rendering scenarios.
GT Server and RasterFoundry has explored the space of rendering definitions a bit more fully and some of that work deserves to be ported upstream to GT. In particular, the InterpolatedColorMap, which selects a color via a linear interpolation on a per-cell basis (rather than computing the colors based on a preconceived notion of how much chromatic resolution is desirable)
https://github.com/geotrellis/geotrellis-server/pull/224
This issue likely demands a bit of reorganization so that low-level rendering facilities can be reused by these higher level abstractions and so that there's a consistent, predictable API for using these rendering-descriptions
