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Colinearity constraint?

stefan_1stefan_1 Member Posts: 7
I may have inadvertently applied SolidWorks thinking to my problem, but is there anything like the "Colinear" contraint for line segments? "Parallel" is almost there, except I can't find how to also constrain a point to lie on the line supporting a line segment.


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    caradoncaradon OS Professional, Mentor Posts: 300 PRO
    edited March 2015
    A simple coincident constraint will do. Works for points/vertices/lines.

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    stefan_1stefan_1 Member Posts: 7
    Thanks a lot - that's what I needed.
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    andrew_troupandrew_troup Member, Mentor Posts: 1,584 ✭✭✭✭✭
    It's good to see OnS taking a hard look at the state of the art MCAD and identifying quite foundational redundancies most of us have never identified when using those packages.

    It reminds me how the elegant simplicity of the original Solidworks dimensioning tool came as a delightful and refreshing surprise. It replaced a whole quiver of dedicated tools in the likes of Microstation, ProE and Mechanical Desktop, not to mention the workstation grade packages like Unigraphics and IDEAS, with no loss of utility (in fact, generally a gain)
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    onshaperonshaper Member, Mentor Posts: 94 ✭✭✭
    edited April 2015
    Hey guys. I'm confused, how is colinear redundant to coincidence?

    Edit: Oh, I see. They put the colinear relationship inside the coincidence function. Clever!

    It does like to dance too!

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    paul_chastellpaul_chastell Onshape Employees Posts: 124
    edited April 2015
    By coincident we mean that the two geometries are in the same location, i.e. two points are 'coincident' if they are on top of each other (thats the obvious one). Two lines are 'coincident' if they are co-linear. Two arcs are 'coincident' if they have equal radius and are concentric, and so on. Rather than have multiple constraints that are essentially the same concept we have one: coincident. Note that in general constraints in Onshape refer to just the thing they are on: so 'coincident' on a line doesn't affect the end points. That's why if you 'use' a linear edge the resulting line has three coincident constraints: the line coincident to the edge and the ends of the line coincident to the vertices. Some of the constraints have to involve the end points by their very nature, such as equal or midpoint, but they are the exception.
    Paul Chastell
    TVP, Onshape R&D
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