---
title: "Output"
url: "https://help.maxon.net/c4d/en-us/Content/html/OFPFLOCK-FP_FLOCK_OBJECT_OUTPUT.html"
section_path: "Simulate Menu > The Simulation System > Particle Modifiers > Flock > Output"
element_id: "OFPFLOCK"
group_id: "FP_FLOCK_OBJECT_OUTPUT"
description: "As of Cinema 4D 2025.1, it is also possible to attach custom properties to the particles, which can then be queried again in Conditions, in Math or Data …"
---

## Output

As of Cinema 4D 2025.1, it is also possible to attach custom properties to the particles, which can then be queried again in *Conditions*, in *Math* or *Data Mapper* modifiers, for example, or offset against other properties of the particles. The *Flock Modifier* offers two properties for storage.

To use the corresponding storage, activate the option to the right of its name. A new custom property whose data type is compatible with the output value is automatically created and entered. These automatically generated custom properties are stored within the *Scene Settings* and their *Particle Simulation* settings and get listed in the *Automatic Custom Properties* section.\
However, you can also go to the group for *Manual Custom Properties* and create your own custom properties there. You will find an arrow button behind the respective name field of the *Output* properties, which can be used to open a selection list of the available custom properties. These lists are automatically filtered to display only the custom properties of the simulation scene whose data types are compatible with the *Output* value.

You can find out more about the manual creation of custom properties for saving and processing particle properties in the section on [Particle Simulation Settings](https://help.maxon.net/c4d/en-us/Content/html/OPBDSCENE-PBDSCENE_FP_GROUP.html.md) within the *Scene Settings*.

When using the following outputs, please note that the setting for **Neighbour Search** is also evaluated for their determination. In simulations with a large number of particles, an incorrect **Particle ID** or an insufficient **Neighbour Count** may therefore be output in the *Fixed* or *Dynamic* modes if too low a value is used for **Maximum Checks**.

### Closest Particle ID

Parameter ID: `FP_FLOCK_OBJECT_OUTPUT_CLOSESTPARTICLE`

The Integer index number of the nearest neighboring particle is output here. If no particle can be found within the search radius, the value -1 is displayed instead. Activating the **Closest Particle ID** option automatically creates a custom property with a suitable *Index* data type. Alternatively, you can click on the arrow button next to the name field to select one of your manually created custom properties that also uses this data type.

### Neighbour Count

Parameter ID: `FP_FLOCK_OBJECT_OUTPUT_NEIGHBOURCOUNT`

This integer value specifies the number of neighboring particles that are within the search radius. Activating the **Neighbour Count** option automatically creates a custom property with a suitable *Integer* data type. Alternatively, you can click on the arrow button next to the name field to select one of your manually created user properties that also uses this data type.

The following video shows an example of a possible use. There, the number of particle neighbors in a Color Mapper is used to color the particles.

[Video: 2025-2_Particles_Flocking_NeighborCount_01.mp4](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2025-2_Particles_Flocking_NeighborCount_01.mp4)