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Generic Rendering

Egon++ is continuing the process of merging the CDK-JCP rendering core into CDK master. Some proposed generification of the classes was made on the mailing list, and here is a sketch of some of the classes and interfaces:
I realise that this looks horribly complex, but the question is : "Is it just complex enough, or too complex?". One of the things missing from the diagram is layout - there may be a need for classes like LinearMoleculeSetLayout or GridMoleculeSetLayout. Oh, and yes (you guessed it!) an IMoleculeSetLayout and ChemObjectLayout classes :)

The goal here is not to make convoluted code, but to avoid repeating stuff. A reaction renderer should know how to layout and paint molecule sets, and then pass on the task to the molecule set renderer, and so on. Some key things to avoid will be a) not to relayout on each paint and b) generate the diagrams in the right places, at the correct scales. I think that this will be possible.

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