Hi,
Here is how to reproduce the bug:
bug or limitation of the history system?
j
I’m seeing the dimension update here when scaling the first line and the dimension does not leave the intersection, see my attached 3dm. If this is not what you set up and I messed up the steps post a 3dm file and I’ll try to help more. Thanks!
Dimension_Update.3dm (35.7 KB)
I Brian,
When scaling the line so that the intersection point remains in place, the dimension sticks to the intersection.
However, when scaling makes the intersection move, the dimension stays in place and doesn’t follow the intersection.
Dim-IntersectionPoint.3dm (41.8 KB)
Thanks for helping to explain the issue. Will this workflow using Intersect with History help? I can file the report as a bug but thought this solution is pretty easy. We need the intersection to be it’s own object rather then a set coordinate at one time which is what the Osnap does.
I guess it all depends on the situation. In a quick test here, that won’t work - if you have a specific distance along the x-axis that that one curve needs to have and you want to scale 1D from start, then horizontally snap to end and then type distance. If you start the scaling from a point in the middle, you’ll have to figure out another way of finding the correct scaling. But I haven’t yet come across a real-life situation where this applies…
Yes, please 
You mention starting the Scale1D at the start of the line and then later say the scaling starts from a point in the middle. I’m not following after a few attempts here, can you make a GIF? Also how does the scenario relate to the intersection point object created with Intersect and History?
I’m having trouble thinking of one as well… but hoped the method I came up with would suffice. I’ll can file a feature request nonetheless, I just want to understand how creating the intersection point object doesn’t work 
Brian,
perhaps you should ask @julien_roger for the real-world application of this problem. I’m just making things up to find a case where the workaround doesn’t work…
In the attached, I’ve put some constraints on the system.
Dim-IntersectionPoint.3dm (52.5 KB)
Let’s say that the start point and the y-value of the end point of the black line is correct but the x-value needs to be on the border line on the right.
By 1D scaling from the start point, you can easily snap to the end point for second entry and the border line for third entry into the command. This will make the intersection with the red line move and the dimension will be left hanging.
If you scale from the intersection as you suggest, the dimension will change correctly but the start point of the black curve will be wrong:
Hi Wim, I understand, it is fun to do that.
However, in the scenario you explained further (thanks), the intersection point and left side end point of the black line cannot remain where they both are while also moving the right side end point of the black line and additionally maintaining it’s Y axis height. The only option I can see to satisfy the new right side end point X location is to change the angle of the black line and therefore the intersection location with the red line. I don’t believe it’s possible to maintain the other conditions with a Scale1D. If an intersection point object is created with history and the aligned dimension created from that point, you will get the correct updated dimension but the intersection point will have to change.
If @julien_roger has more info on the real world application of this request that’s great. I’d like to know how my proposed technique works for them as well.
Yes, that was my point. And I read @julien_roger problem as being just that.
But I could be wrong…
Hi Brian,
it is not a real problem for me, I just supposed it could be a bug.
Thanks
