Drawing shapes in Flex / Actionscript

I want to develop an image editing application in Flex 4. My initial requirement is to draw various shapes like Line, Rectablge, Triangle, Circle, Star etc in appication. I want to facilitate user to draw shapes using rubber banding like professional applications do.

All shapes would be vector and should look smooth in an size. So, can't use bitmap and scale them.

What are better开发者_如何转开发 methods to achieve this?

if you don't want to start from scratch with the basic shapes, there is this framework called degrafa: http://www.degrafa.org/

they have plenty of parametric shapes & curves and advanced features to organize them together.

Make shape editor with some control points. Control points are draggable sprites (circles or squares as you like). When control point is moved, editor must be updated - it may be resize or move action. On resize, draw your vector shape according to new size. The easiest way to make sprite draggable is startDrag() function - you can also set limits there (to stay in editor area or to disable negative sizes).

I have done such editors based on Sprites, added into Flex application with rawChildren.addChild, but you can try to use Canvases instead of Sprites if you wish.