opExtrude UP_TO_FACE Issue

aaron_skidmore

Hi there, when I opExtrude as per below if the regionToExtrude is within the boundaries of the bottomface, it works ok, but if the regionToExtrude is outside the boundaries of the bottomface it doesnt work, is this expected behavior?  

opExtrude(context, id + "extrude1",
       { "entities" : regionToExtrude, 
        "direction" : zDirection *-1,
        "endBound" : BoundingType.UP_TO_FACE,   
        "endBoundEntity" : qNthElement(bottomface, 0),
        "operationType" : NewBodyOperationType.NEW,

        "defaultScope" : true

    });

NeilCooke

Yes it is. If in doubt, try to replicate your use case using the regular modelling tools. 

aaron_skidmore

Thanks Neil, so would I need to create a plane on the bottomface, then set endBoundEntity to that plane?

NeilCooke

Is bottomface planar? If so, that would work. If bottomface is parallel to your sketch plane, measure the distance and use blind. 

aaron_skidmore

Thanks Neil, I will go with measuring the distance and blind

Jake_Rosenfeld

@aaron_skidmore

UP_TO_FACE is a deprecated option.  Please use UP_TO_SURFACE instead, which will expand the given face to its infinite boundary, if possible.  See: https://cad.onshape.com/FsDoc/library.html#BoundingType

Internally, when selecting the "Up to face" option in the extrude feature, you are actually selecting UP_TO_SURFACE enum.  See the implementation here:
https://cad.onshape.com/documents/12312312345abcabcabcdeff/w/a855e4161c814f2e9ab3698a/e/0ef5bec0909d4235a5ca1ebb

aaron_skidmore

Thanks I have that all running now.

I am now struggling to find a way to get a solid bodies that intersection another solid body, via evCollision ? Or qIntersection ?

NeilCooke

evCollision tells you if the bodies collide. If you want to find the resultant body created by the intersection of two bodies use opBoolean. qIntersection is the intersection of two queries (not what you want here). 

aaron_skidmore

Ni Neil, I am not after the intersection between the 2 bodies, I need given bodyA, what other bodies are intersecting bodyA, do I need to get all bodies and  recursively run evCollision to test which ones intersect bodyA? 

NeilCooke

evCollision will return an array of all collisions.

aaron_skidmore

So I could try to cycle through bodies 1 at a time testing evCollision against the selected body - if there is any collision arrays then that body intersects? Could the same thing be done with multiple qIntersextion?

Jake_Rosenfeld

@aaron_skidmore

qIntersection is not a geometric concept.  It is just a simple set intersection.  For example if I had two queries that represented:

[face1, face3, face5] and [face1, face2, face3]

The intersection of those two queries is [face1, face3]

Similar to qUnion and qSubtraction, it is just a way to combine, find the overlap, or remove queries from each other.  See: https://cad.onshape.com/FsDoc/library.html#qIntersection-array

evCollision ( https://cad.onshape.com/FsDoc/library.html#evCollision-Context-map ) will happily collide with multiple bodies at once.  

const collisions = evCollision(context, { "tools" : bodyA, "targets" : qEverything(EntityType.BODY) -> qBodyType(BodyType.SOLID) });

var targetBodyArray = [];
for (var collision in collisions)
{
    targetBodyArray = append(targetBodyArray, collision.targetBody)
}

// To de-duplicate, since collisions are per-face/edge
const allTargetBodies = qUnion(targetBodyArray);

debug(context, allTargetBodies);

Jake_Rosenfeld

The weird -> thing is supposed to just be "->".  Not sure what's going on there...

aaron_skidmore

Thanks for you help guys - I will try and get that to work - i think I have bitten off more than I can chew for my first go at a FeatureScript!