the canvas object seems really basic at the moment, it cant darw elipses, or polygons between points, also perhaps set the possibility of removing from the canvas, so lets say you want to draw detructible terrain, you simply plot an elipse, and set it to erase from canvas object (value 1 is no value 2 is yes) something like that., if u were to say erase from canvas object with an ellipse/polygon that was lets say 50% transparent, it would leave a 50% transparent spot on the canvas, which you could see through.
i really believe polygons which u set the point for like draw shape with points 1.x,1.y,2.x,2.y,3.x,3.y ect ect, (no limit so you can make any number of points that youd like.)
should exist also, mmf2's overlay object is quite better than the canvas object, not enough properties are defineable. and essential features like drawing circles and erasing certain areas with those shapes or pasted sprites are inexistant.
a canvas object is really good if you want breakable terrain, and you cant do that with it!