I'm trying to make a big triangle made with smaller triangles with spaces in between (kinda like the triforce but with 9 triangles per side). Thing is the "triangles" have actually other stuff underneath, so I want to use array. How do I stack them without ending up with a parallelogram?
Sorry for the low quality picture but I can't upload from my computer right now. This is how the top should look like, but just half of it (so a triangle, not a parallelogram).
I don't think there is a way to do this with modifiers alone, apart form applying them and edit the result manually.
You can Apply your modifiers (from the top down), then go into Edit mode and select and delete the parts you don't want.
Alternatively you could download, install and activate the Array Tools add-on. It allows for a variation for each new row (like -1 triangle). The add-on however does not work with modifiers and every triangle would be a separate object.
Example of the add-on:
Add an empty and position it exactly at the same x as the tip of your pyramid. Add a mirror modifier with Bisect and Flip enabled. Set the mirror object to your empty.
This will mirror every geometry sitting on the left of the x plane but ditch everything on the right of this plane.
If you don't want to have a seam in the middle, add a decimate modifier set to planar after the mirror.
Before :
After :
