Suggestions for building a level editor

[edzillion]

Hi

Had a look at your engine, and it's very useful. Thanks!
I had a quick go at building a really simple level editor by just making a loop to dump a button for each glyph to the screen. The thing is, apparently it's impossible to determine whether a glyph is present in the font or not.

There is a technique of writing the font to the screen and then matching the pixels of the glyph to the (browser & platform dependent) 'missing glyph' character. I am not even sure I could get the implementation working, but even so it seems an inefficient solution.

The other option is to export the 'cmap table' using something like font-cmap which (I think) is a list of all the glyphs present with their unicode values.

Any suggestions here? Can't seem to find an editor built with this, any examples you know of?

thanks for your time