A method and system for digitally coloring, compositing, selecting, or segmenting, anti-aliased or grayscale or multi-color line art or graphics, uses a set of acquired “image points” with properties such as coordinates, color, “paint” and “flow” status, etc. According to preferred embodiments of the invention, “unpainted” and “painted” “image points” are acquired by a processing device, which iterates through an ordered set of “reference colors”, in descending order. For each “reference color”, the device determines “unpainted image points” for which: the point's color is “greater than or equal to” the current “reference color”, except for “lesser flow” or “list” status, and: the point is “threshold adjacent” to a “painted image point”. The point's status thus changes to “painted”, and the point takes the color or “segment affiliation” of the “threshold adjacent” point, with optional prioritization. The user can adjust “image point” properties, e.g. when performing color flatting.