Trying to array a group of curves, but it's only arraying one of them. What's wrong?

The “X” shape is two lines grouped together. I’m trying to array the “X” along a group of other curves which make up a contour map.

My setup is almost working, except it’s only arraying one line from the “X” curve group. On the [CRV] node, I clicked Set multiple curves and selected my curve group. As you can see, when [CRV] is selected, the whole group is selected in the viewport.

So why is it only arraying a single curve within the group?

If I understand it correctly, your curves are grouped together in Rhino but grasshopper doesn’t know/care about that. You’ll need to run those curves through a “group” component in grasshopper.

Other than that it’s hard to give you much help since you’re not providing your file (with internalised geometry) to look at.

I fed the [CRV], which is 2 curves ( the \ and /), into a group element. It had no affect. It’s still only arraying one of the curves from this group.

That’s not the component that groups geometry. That’s the component that contains a collection of groups. When you feed it geometry which is not groups of geometry, it converts each object to a group.

Orient placed one of your curves at the beginning and repeated the second curve for all the other positions. This happens when you don’t understand data trees. Without posting your file, you’re lucky to get this much of a hint.

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X (8.7 KB) test.3dm (306.7 KB)

But you’ve already solved it since posting these 2 files. I had no idea there were two “GROUP” nodes (not exactly instantly intuitive…)

Adding the group node to the two X curves solved it. Thanks.

There are several ways to solve this. Here is the simplest way, without Group. Geometry is internalized so no need for the Rhino 7 file, this GH file can be opened in Rhino 6. (143.0 KB)

Here is another way using a single point (which defaults to World XY at the intersection point) as the Orient ‘A’ input.

X_marks_2020Aug25b (143.1 KB)

Thank you for both of these options. Could I lob one more Q your way?

I’d like to force the orientation of the X to always face the active perspective camera, such that the X’s are always perfectly straight (no rotation) and perpendicular (facing directly at the camera). Therefore, they would appear more like 2D elements, placed on top of the 3D contour lines below.

Any additional insight on how I might approach this?

You could use the PCharge (Point Charge) symbol instead of your “X”. (140.0 KB)

Otherwise, I have no idea.