wp, circular, seenkao, thank you individually.
wp, I'm trying to run the demo you posted. I hope it works.
circular, I hope you add these features to a BGRAbitmap, and we pray for you.
seenkao, my path will definitely cross with the triangulation process one day. This is an issue that I am aware of but always avoid.
If I can't find an easier way, I'll gradually learn to triangulate.