Curve Wall and Slab Problem

[Anonymous]

i have problem with Curved wall and slab at intersect.
i think a reason is difference resolution between wall and slab edge.
i draw slab with curve edge first, and then is Wall with outline Polygon with Magic Wand.
Problem appear with exterior plaster of this wall on below pict.
solution for this ? thanks

[Barry Kelly]

Are you referring to the line just up from the bottom of your image?
Is that the slab/wall join?

How did you match the slab and the wall curve?
Did you use the magic wand?
If so is it set to 'Best Match' rather than 'Linear' in the magic wand settings?

Barry.

[Barry Kelly]

There does indeed seem to be a problem here.
I placed a large slab under a wall and then used the magic wand (best fit) to cut away the slab to match the wall.
The outside of the curve matches perfectly - or I should say the reference line side of the wall matches perfectly.
But the inside (or non reference line side) does not quite match.


In this image I swapped the wall reference line to the other (inside) of the curve and did a much smaller radius just to try to exaggerate the problem.
Looking from below you can see how the non-reference side of the wall does not match the curve of the slab.


As I think you have assumed, there is no such thing as a true curve in Archicad.
I think the problem is that both sides of the curved slab are independent from each other, so the algorithm that creates the straight segments have no relationship to the other side.
The segments on each side are exactly the same length.

Whereas the wall, because it has just the one reference line, that is the line that is divided up into the straight segments.
The other side of the wall has just as many segments - creating essentially wedge shapes that join together to form the wall.
So one side of the wedge is slightly longer or shorter than the other side.
This will not match the slab.

If that side of the wall you show is 'critical' (has to be correct, then I would try swapping the reference line to that side and then re-create the slab curve.

Barry.

[Anonymous]

Thanks Barry.
That's exactly what I did with the wall.
means that I will have to draw on the reference line of the wall and not use the Offset command
a bit tired, but I think that would be the best way to draw with these shapes.
Archicad is still not perfect enough for free drawing