Add image visualization as type of script to generate testcase images

[eldering]

Currently we support having testcase images, but only loaded statically. We should have a new type of script to both be able generate those during import and also to generate them from team output, in case the visualization depends on the output and then also display those in the jury interface for visual comparison.

[meisterT]

I seem to remember that you have a prototype of this, is that correct?

[eldering]

I started looking into it, but no prototype yet. All I have is https://github.com/eldering/domjudge/tree/testcase-image-gen

[nickygerritsen]

Some points:

• We want to visualize after the result is known to the team (and jury)
• We want to run the visualizer on the judgehost

[meisterT]

In the discussion just now, it came up that this could a judgetask.

[vmcj]

@eldering looking at the problem spec it seems to hint that a generator for testcases should be run before import, I would say that a (testcase)visualization_generator should by the same logic also be ran before the import.

So should we only visualize the output of teams? I see an usecase for that or do you want both features?

[eldering]

@eldering looking at the problem spec it seems to hint that a generator for testcases should be run before import, I would say that a (testcase)visualization_generator should by the same logic also be ran before the import.

So should we only visualize the output of teams? I see an usecase for that or do you want both features?

Yes, this only applies to team output in the current context.