Half thickness polylines.

[Anonymous]

I am having to mark up a lot of "Plan Edged Red" type drawings for Land Reg for a bunch of apartments.
In AutoCAD, there is a "half width polyline" option, so the centreline is on the boundary and the wide-half-line extends inwards. It remains exactly on the edge regardless of output scale.
Can't find an equivalent in AC11.
I can set a red line 2.0 or 3.0mm wide but it overhangs.
I can offset the polyline inwards 1.5mm so it works at one scale, but it is still wrong at any other.

Am I missing something?
How do you deal with this problem?

[Thomas Holm]

I don't think there is an offset polyline option in Archicad. A custom linetype might be able to get close, but still it's precision would depend on the lineweight and scale chosen.

A workaround might be to use the wall tool. With a solid fill and both edge and fill pens with 0 (zero) width and the reference line at one side, you'll get the appearance and precision you want. You'll of course have to draw the segments of a segmented line individually (or split the line and delete every other segment), but it's doable. The Multiply command with the Distribute option might be helpful.

[Anonymous]

Thanks Tom,
Not thought of that but it should work ok.
Ended up using a gradient fill over the whole area, pale pink centre to red at the periphery, which worked for the big site areas but not so good for the Apartments.
Will change them all to the Red Walls tomw.
Good Call.
Thanks.

[Thomas Holm]

You're welcome!