* I doubt anyone will notice the file->open filter unless they look for
it so it's no good for 'discovering' the image viewing capability, but
it might be convenient for people who know about it.
* This will allow the adding of things like 'redundant api call' for calls
that have no effect, as well as potential problems like drawing with an
empty viewport, or similar things that are common problems. Reading out-
of-bounds on buffers etc is a good example of 'defined' behaviour that
is probably not desired.
* These heuristics could also identify potential performance problems.
* It also supports adding debug messages after log-load time, so you could
do an additional extra-strength pass, or do a detailed check of one
draw call (e.g. a broken draw, to try and figure out the problem). If
there are any unread debug messages, the status bar will flash and the
debug messages window will show a count as (N).