intersection constraint in sketcher?

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dimitar
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intersection constraint in sketcher?

Postby dimitar » Thu Jul 11, 2019 5:51 pm

Hi I am wondering if there is a way to create a constraing based on two intersecting lines in sketcher. I know it can be done with two constraints for each of the lines, but I am wondering whether it can be done with a single constraint?
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saso
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Re: intersection constraint in sketcher?

Postby saso » Thu Jul 11, 2019 6:37 pm

add a point?
chrisb
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Re: intersection constraint in sketcher?

Postby chrisb » Thu Jul 11, 2019 10:16 pm

Can you elaborate what you want?
In Sketcher many of the constraints work on infinite lines rather than on the line segments which you draw in sketcher, e.g. point-on-object: a point on the line does not have to lie between the endpoints; or tangency: the "tangent" lines don't even need to touch (which ca be seen as a contradiction to the term "tangent").

Following that concept all non parallel lines would intersect, so it would not be a very helpful solution.
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dimitar
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Re: intersection constraint in sketcher?

Postby dimitar » Fri Jul 12, 2019 12:17 am

this is what i mean by snapping at an intersection
line.gif
line.gif (90.74 KiB) Viewed 86 times
But your point is well taken, and it makes sense. Thanks for explaining :)
chrisb
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Re: intersection constraint in sketcher?

Postby chrisb » Fri Jul 12, 2019 6:01 am

For this you have to follow saso's recommendation and and add a point with point-on-object on both lines.
openBrain
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Re: intersection constraint in sketcher?

Postby openBrain » Fri Jul 12, 2019 12:25 pm

Or in the case where the line ends just at the intersection, simply constrains the line endpoint to the 2 intersecting lines with "point-on-object" constraints. ;)
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DeepSOIC
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Re: intersection constraint in sketcher?

Postby DeepSOIC » Fri Jul 12, 2019 1:09 pm

The two
dimitar wrote:
Thu Jul 11, 2019 5:51 pm
I know it can be done with two constraints for each of the lines, but I am wondering whether it can be done with a single constraint?
Select the TWO edges and the point, and apply point-on-object constraint. This creates two constraints in one go. You can also constrain several points to be on one edge, similarly.
chrisb
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Re: intersection constraint in sketcher?

Postby chrisb » Fri Jul 12, 2019 2:28 pm

DeepSOIC wrote:
Fri Jul 12, 2019 1:09 pm
Select the TWO edges and the point, and apply point-on-object constraint. This creates two constraints in one go. You can also constrain several points to be on one edge, similarly.
Every day there is something to be learned from here: I knew the latter, but never thought of the former.

Thanks for telling!