@sozap the problem with scaling is that some of those assets are narturally big & bushy, but some have very small versions of themselves, so the idea with the bounding box size and swapping for a smaller asset from the pool of scattered items sounds good to me, but will ultimately depend on the asset type.
Another application would be a rooftop garden with a layer of grass. I’m using GeoScatter for all those things, and it does a mighty good job giving me lots of options - I can define collections the scatter keeps a defined distance around, with a defined transition area. So with grass, this works well, and depending on the size of the scattered grass clump I get a reasonably small gap.
Large clumps/models would get pushed away too far in their entirety. Hence the thoughts on clipping.
If realizing the instances is the only key, or permanently altering the asset shaders, OK. The “problematic” assets are limited in number. Sometimes my clients want to swap foliage, just one type of asset. OK, I could still keep the scatter system hidden on a separate hidden emitter, delete the realized instances and swap out the specific item.
I’m very much for cutting (clipping)! I’m looking for a simple solution, and @zeroskilz’ seems very straightforward. Now, Terrascape’s Grass Scapes pack has around 260 (gr)assets using around 200 materials in total (very roughly counted), of which I realistically would only have to modify the leaf materials, i.e. 2/3 of those materials.
My problem: I’m a node dummy. There is not one single texture coordinate node in those specific materials, just a “group input”, 1 color map, 2 bump maps, a couple of adjustment & mixing nodes, I understand all but the group input node. HOWEVER, I suspect that could not work, especially not automagically, since, I’m guessing, the materials, depending on who created them, have very different builds - so I, with my limited understanding, am back to square 1 
Maybe the bounding boxes can be clipped and with them the contained mesh?
I’m really sorry, I’m trying to grasp and/or “modify” very complex scenarios with primitive, uninformed input. I understand this isn’t Lego. I just thought clipping ojects/instances would be a lot easier. But then people would already be doing it…
@Okidoki it’s not just for one balcony with some planters. It’s every single house plant placed in a corner or wherever. You get a HUGE bounding box dropping items from the asset browser, that sometimes reflects the size of the asset, sometimes doesn’t. If I could easily just have them clipped by the adjacent walls, that would save me trying 6 different assets. In real life (I DO understand the difference, still ) you just push the plant where you want it and the leaves will bend away, if necessary. physically, I’m sure this is very hard to achieve, but maybe it can be faked easily…
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