rdInst Tutorial 38 – Using the rdPopulateActor

Last Updated: 14th July 2024
Tutorial created with rdInst version 1.41
Download Demo Project (32MB, UE5.3.2)

Version 1.35 of rdInst introduces a new tool based off the Population Blueprint from Tutorial 22.

This tool is Subclassed from the rdSpawnStuffActor and has all the placement settings and Scalability levels etc contained in that.

This Actor gives you the ability to place objects either in 3d space or on a landscape with many placement options including slope fixing, splatmaps, grid aligning and random positioning.

You also have the option to bake the position data down into a tight table which can be used to spawn on-the-fly and scan through for fast overlaps.

This tutorial creates a PopulateActor which populates a level with trees and plants.

Step 1. Create a new level and add your foliage assets to the project

Firstly, create a project and an Open World level. If you have your own foliage, add it to your project, or use the foliage linked to in the demo project at the top of this page.

Step 2. Add a rdProceduralActor to the level

Now go to Place Actors and search for “Procedural”. Drag the actor onto the level. Set the scale of the actor to fill the area you’re wanting to place objects in. A X&Y scale of 1000 fits nicely in the level area in the middle of the landscape. Make sure the bottom of the volume box is below the minimum height of the encompassed landscape.

Step 3. Add the meshes to the actor

Select the meshes you’re wanting to add to the ProceduralActor and drag them into the area labelled “Drag in Meshes” (the list will highlight). This fills in the populate data for each mesh you’ve dragged in.

Step 4. Set the populate settings

Now Expand the “Spawn Data” array and expand the “Items” array – there will be one item for each mesh you dragged in.

We’re just going to use the defaults in this tutorial, but it’s useful to know where to find these settings.

Now collapse the Items list and change the Grid Width and Height to 200 – the smaller the grid size, the more dense the population will be.

Step 5. Done.

Now you can use it like this, or click the “Bake SpawnStuff Data” to bake the mesh data into a compact table for fast spawning and proxy scanning.