Provide a facility by which a filter can output one or more tuples for debugging can be displayed in the UI by moving the mouse over the preview image. The tuples that the filter outputs for the selected pixel will then be displayed somewhere in the UI.

The user should be able to select a point in the image which is passed into the filter as a user value. Useful for setting center points and probably lots of other stuff.

When adding a new node in the designer, automatically connect the currently selected node's output to the new node's input, if it has one.

Right now if the viewpoint is changed new nodes show up where the viewpoint was at the start, which might be a long way away from where it is now.

It should be possible to select an image for the first input image, i.e. it shouldn't be hard-wired to the image that MathMap was called on. This is necessary for doing operations which enlarge an image, for example.

Necessary to implement the "Color" Gimp layer mode.

Something similar to #include, but smarter, to build filters from others. Not sure how to deal with filters that have the same names.

That would simplify the installation and obviate the need for path-searching.

Right now convolution isn't very useful, because precise kernels are very hard to create. Figure something out.

Right now that argument is a boolean, and if it's true, the kernel is normalized to 1. It should be the value to normalize the kernel to, or 0 if it shouldn't be normalized.

Filter arguments should be assignable. See

http://groups.google.com/group/mathmap/browse_thread/thread/da0f0581309d60c4