Sometimes a particle system is just to much for a simple scattering of objects. In these cases the scatter objects add-on is a neat package that give us just enough control for scattering of objects on a surface.
How to use the scatter objects add-on in Blender? Enable the Scatter Objects add-on. Select objects to scatter while holding shift, select the object to scatter your selection on last. Press F3 and type "scatter" and enter. Paint on your target object. Press enter to confirm.
We will continue to look at use cases for the scatter objects add-on and have some fun exploring its possibilities.
The scatter object add-on works by painting one or more paint strokes on the surface of an object. A set of other objects will be scattered along the stroke. Depending on some settings the objects can be scattered along the line.
We can have the objects lined up on the stroke or scattered. With random rotation and distributed in an area around the stroke or all lined up in the same direction. There are few settings, but for a quick scattering this is great. No need to fire up a full particle system.
We can start by enabling the add-on. In the current release we do this by going to Edit-> Preferences and find the add-on section. Type "scatter" in the search box and the list should filter.
Check the checkbox next to the add-on name to enable it.
The add-on has some settings under the workspace tab in the properties panel. The section is called "Object scatter".
To use the add-on we need to select one or more objects to be scattered. In the same selection we need to select the object that we want to scatter our objects on.
Shift select the objects, and last select the object that you want to scatter on. The last selected object will be the active object. It will have a light orange outline as opposed to the selected, but not active, objects. They will instead have a darker orange color outline. These colors are also reflected in the outliner.
Once you nailed the selection, hit F3 with your mouse in the 3D viewport and type "scatter". This will filter the search down to the scatter object operation that is added by the add-on.
Press enter to confirm. Just remember that when you have hit enter the scatter object settings can no longer be used.
If you find yourself using scatter objects often, you can add it to your quick favorites. Right click the search entry and select "add to quick favorites". To later access quick favorites, press "q".
Back to the scatter objects add-on. From the search, chose the scatter object entry in the list and nothing will appear to have happened. However, you can now start to paint on the active object with your mouse and blue cubes will appear around the stroke as a preview.
This is also the stage where you can use the settings in the properties panel to adjust how the objects are scattered. Once you hit enter the settings will be confirmed. Each cube will then be replaced with one of the objects in your selection.
Let's now have a look at the available settings.
|Density||The amount of objects that will be scattered.|
|Radius|| How far away from the line the objects will be added.|
Scale how large these objects will be.
|Randomness||Adds randomness to the scale of the objects.|
|Rotation||The objects already have a random rotation in the normal direction of the object they are scattered on. Rotation will add rotation for the other axis as well.|
|Offset||How far above the active object surface the objects will be scattered.|
|Seed||Changes the random distribution.|
These are all the available options. Together they are quite powerful for quick and random distribution of objects. Much faster than setting up a particle system but also a bit limited.
You will notice that we are not completely done at this point. If your active object is in the middle of the scene you will notice that a copy of each object that is being distributed is also created here.
These copies are also children of the instances that is being duplicated across the surface. You can't move them without moving the entire distribution.
There are a couple of ways we can get around this. The first way is to select all the distributed instances without selecting the objects positioned in the middle. Then hit "ctrl+a" and choose "Make instances real" at the bottom.
Now all the instances are separate objects, but they still contain linked data to all other instances.
The second method is to be a bit more proactive about this. We know that the duplicates will be copied to the center of the world. If we therefore make sure that the active object that we distribute instances on top is located somewhere else, we won't have this problem. Keep in mind that the copies will still need to be located in relation to the active object.
So, when do we use the scatter objects add-on and when do we go to a particle system? I would generally say that when you need something more advanced than scattering a handful of objects around, a particle system is the way to go. But this add-on is great when we need to add some detail or scatter anything in lower quantities.
Think about rubble or garbage lying around or certain spices of flowers on the forest floor. There are quite a lot of use cases for just simple scattering of objects.
For heavy tasks though, particle systems are still the best bet. They bring many more options and for anything that uses moving parts like forces, physics or animation particle system is the only option.
A cool trick that you can use is to combine scatter object with metaballs. This way it is easy to create some spilled liquid or splattered oatmeal. I also found this useful when creating frosting on digital cakes.
Scatter objects uses instancing to duplicate the objects and metaballs can become really weird when combined with instancing.
Still, there are ways we can get around this and have our metaballs be useful with the scatter objects add-on.
You can now work with your metaballs distribution like any regular mesh.
This method is not very compatible with animation though.
What is the grease scatter object add-on?
The grease scatter object add-on has been replaced with this add-on in 2.80 and later. It used the grease pencil tool to draw the line instead and scattered a group of objects around the strokes. The scatter objects add-on is way quicker to use though.