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Fixed Constraint not actually fixed. Or is it?
When in sketch mode and you fix constraint on a line. the endpoints are not constrained only the angle of the line and where that line exists in space. Adding a single dimension to each endpoint will then finish fixing the line. BUT when I fix a spline it constrains everything about it even the end points. Any reason why a line does not behave the same way when fixed?
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bladec
Member Posts: 17 ✭✭
Seems like this is just due to the coincident constraints on the handles. If you delete those you can move the ends of the spline.
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Seems like this is just due to the coincident constraints on the handles. If you delete those you can move the ends of the spline.
Ah that does explain it....I suppose.
In geometry, the strict definition of a 'line' states that it has infinite length. So, I'm guessing it's something to do with that.
CADNurd's Linktree - find me everywhere else - https://linktr.ee/Liam.G
not so much asking about geometry. more so how onshape "thinks". or what assumptions are made and why
No, you're right. It doesn't make much sense. Also, why can't you box-select a line endpoint?
CADNurd's Linktree - find me everywhere else - https://linktr.ee/Liam.G
This is consistent with how constraints work for other sketch entities. For example a line can be black even if the endpoints can move. Same for an arc.
So if you select the line/arc/curve and "fix" it, the end points aren't necessarily fixed.
Splines are even weirder. The first and last control point can be independent of the actual endpoints of the curve. The default to being constrained, so this usually happens by mistake.
Offset curves also have independent end points which are oddly not constrained by default. This drives me nuts.
Intersection curves do have constrained end points by default, but those constraints are independent of the intersection constraint(s) on the edge(s).
Simon Gatrall | Product Development, Engineering, Design, Onshape | Ex- IDEO, PCH, Unagi, Carbon | LinkedIn