Symbols and Elements

I have made attempts over the years to draw triangles and circles like, for example, this:

(in fact, this was drawn by David Westhead's code). There is a small design decision to be made between representing drawing elements as basic geometry or as symbols. A symbol may be the same as a geometric element (like a circle), but it might be a combination of them. Consider the 'N' and 'C' in boxes, above. Or this image:

where the mass number and charge are separate text elements on the left, and part of the whole symbol on the right. Neither is a 'better' way of doing things; they each have their advantages - and disadvantages.

It can be a lot clearer to use symbols, as each model object (atom, bond, helix, gene, cell) has a corresponding representation, and then a diagram composes the symbols into a manageable whole. On the other hand, you can re-use elements in different combinations for diagrams. A general vector drawing package would have Line, Text, Rectangle, Triangle, and so on.

So my vote would be to use symbols for the CDK/JCP renderer. The JCP application is not intended to be a full vector drawing package, but a specialised chemical editor.

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Adamantane, Diamantane, Twistane

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