Sorry if my first posting above was a bit off-topic !
As well as border corners, it would also be nice to see an ellipse property.
Obviously, the layout of non-rectangular shapes in a browser is going to be alot more difficult than plain boxes.
I would like to propose that an ellipse object would be automatically assigned to living inside it’s own unique parent block object.
The four center points of each side of the parent block that an ellipse object lives in, could be used to calculate the arc of the ellipse’s sides.
So for a parent block that is say, 200px high, by 200px wide, the ellipse object inside it would be drawn by the browser as a perfect circle, with a diameter of 200px, +- 1 or 2 px.
The shape and size of the ellipse would be dependent on the dimensions of the parent block the ellipse object lives in.
As the ellipse object lives inside a block object, all the browser has to do to position the ellipse object, is to layout the parent block object that the ellipse object lives in.
The ‘live area’ of the ellipse, eg for mouse-overs, should only extend to the border of the ellipse, and not the parent block’s outer border.
I hope this all makes sense!