3ds max-like Array Tool?

[essimoon]

Hi there fellow UE4 users,

I'm pretty new to the engine and just experimenting a bit with blueprints. I think the concept behind it is just amazing!
Now after getting through the tutorial series on youtube I ended up with a tool that can fill a given distance between two points with meshes right inside the editor. Pretty cool to build walls and stuff.
Now I wondered if I can manage to modifiy this tool to also arrange objects in a circle like the array tool in 3ds max does.
After some time I noticed I seem to lack some knowledge of the math necessary for this.

Could anyone please give me a hint on how to do that?

[Michael Noland]

Hi essimoon,

A parametric equation for a circle is:

Position = (UnitX * Radius * cosine(Theta)) + (UnitY * Radius * sine(Theta))

Where you vary Theta from 0 to 2*Pi radians (or 0 to 360 degrees).

UnitX and UnitY are the basis vectors of the plane you want the circle to be in (e.g., (1,0,0) and (0,1,0) if you want it in the XY plane).

Run a for loop for the number of objects you want to create and figure out what Theta should be for each one based on the total number (e.g., if you have 4 objects, you want 90 degrees between them, starting at 0).

Cheers,
Michael Noland

[DotCam]

For an example of how this is done, download the Content Examples demo from the marketplace if you haven't already, and create a project, then open it.
In the project's content browser you will find a blueprint called "BP_RadialArray" in the "ExampleContent -> Blueprints -> Blueprints" folder that does pretty much everything you are looking to achieve. It shows how to set this up in the construction script so that you can change the number of elements in the array, as well as the radius and other options.

Hope this helps!