Need some advice on my suggestion of recolor-artwork tool based on Illustrator's similar tool.
Advantages of the tool: 
1.) Lets you manage interdependence of colors. For example, you select a circle and a rectangle respectively colored RED and ORANGE. For some reason you want to port the whole 'tone' to something cooler. You select the two objects on the canvas, lock their nodes on the color wheel and rotate the rays of the objects to the blue wedge area of the wheel. Now with a single step you can manage the color tones and relationship of different objects. This should prove very beneficial for designers/artists. 

My Blueprint:

1.) Get the colorwheel drawn using the source files "gimpcolorwheel.c" as reference.
2.) Get the GUI for selected objects (based on the XML Tree) [First prototype will only handles solid colors]
3.) Functions for locking the nodes, rotation, dragging etc. 

Any inputs / advice / suggestions are heartily welcome. 
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