Mask questions

Hi,

I have read as much as I can about masks, but I still have a couple of questions.

I am drawing a line chart, the line is a sprite.

Over this, each point is plotted as a sprite these are children of the line. These points change onMouseOver and have onClick etc.

This shows what I am trying to do, but at the moment I am using the background colour:

http://teethgrinder.co.uk/open-flash-chart/gallery-data.php

I would like to make the points hollow so they cut out the line below. So say I have a point at 5,5 currently the line will go to 5,5 and a child sprite is placed there. I would like to cut a hole out of the line so you can see the background grid through it.

I tried using a mask, but the mask erases both the line and the child.

Is there a way of drawing a circle with alpha 0 that ‘erases’ part of the line?

Can I somehow use the alpha of the child sprite to erase part of the line?

I think what I want to do is fill the mask with 0x000000 and punch out holes in it.

Or something.

Many thanks,

monk.e.boy