Get started#

Your first AI in five minutes. Blueprint only: no C++, no Behavior Tree.

Five steps#

1. 1

   Install APS

   In the Epic Games Launcher, open Library → Fab Library, find APS - Advanced Perception System and click Install to Engine. Then, in your project: Edit → Plugins, search Advanced Perception, tick its box and restart the editor.

   

   Go deeperInstall it into one project instead

   1. Close the editor.
   2. Copy the APS folder into YourProject/Plugins/APS/. The APS.uplugin file must sit directly in that folder.
   3. Open APS.uplugin in a text editor and make sure it has the line "EnabledByDefault": false, (put it under "CanContainContent" if it's missing).
   4. Reopen the project. On a Blueprint-only project, accept when the editor offers to build the module.
   5. Edit → Plugins → APS → Enabled, and restart.

   Why step 3 matters: without it, the packager can't tell that a Blueprint-only project needs APS built into its game. Packaging then stops with "does not look like uproject file but no targets have been found!", or ships Unreal's prebuilt game, without APS, which logs "Plugin 'APS' failed to load". Installs from Fab already behave the right way.

2. 2

   Create a Perception Profile

   In the Content Browser: right-click → Miscellaneous → Data Asset → type Perception and pick PerceptionProfile → Select → name it DA_Profile_Guard.

   

   The profile is everything this AI perceives and how sharply. One profile per kind of AI: a guard, a dog, a camera.

   Go deeperWhy it works before you change anything

   A new profile already has Vision Sense and Hearing Sense in its Sense Classes, and every other setting has a working default. An empty list would make the AI perceive nothing at all, which is the most common first-run mistake, so the two senses almost every game wants are already in.

3. 3

   Add APS Core to your AI

   Open your AI character Blueprint (a Character or Pawn, for example BP_Guard). No AI yet? In the Content Browser: right-click → Blueprint Class → Character → name it BP_Guard. In the Components panel, click Add and type aps: every APS component is listed. Pick APS Core.

   

   It appears in the Components list as PerceptionCore. Select it and, in its Details, set APS › Config › Profile to DA_Profile_Guard. Tick APS › View › Show Visualizer to see what it sees while you play. Drawing it costs about 0.3 ms a frame per AI: fine for a few, but leave it off on a crowd (Performance).

   

4. 4

   React when it spots you

   Select PerceptionCore (the APS Core), and at the bottom of its Details, under Events, click + next to On AI Detect. The event appears in the graph, already connected. Add a Print String to it, or an AI MoveTo to send the guard after you. Do the same for On AI Lost.

   

   

5. 5

   Press Play

   Drop the guard in your level and walk into its view.

   You will see:

   • its view cone and lines to the points of you it can see,
   • a panel in the top right corner: its state, a confidence graph and one row per sense,
   • its state floating above you,
   • your Print String once it is sure enough to detect you.

   Step behind a wall and watch it go Detected → Lost, then fade to Remembered and Expired.

Play the demo#

The demo comes inside APS: a hub with one wing per feature, holding the rooms the feature pages point to.

1. In the Content Browser, click Settings and tick Show Plugin Content. Installed from Fab? Tick Show Engine Content too: APS is then an engine plugin.
2. Open Plugins › APS - Advanced Perception System › Demo › Maps. From Fab it is under Engine › Plugins; older engines add Content to the folder's name.
3. Double-click L_MainMenu and press Play.

The demo is lit with Lumen, the default for a new Unreal 5 project. If its rooms look washed out, or the screen shows a red line about distance fields, open Project Settings → Rendering and set Dynamic Global Illumination Method and Reflection Method to Lumen and tick Generate Mesh Distance Fields (the editor asks to restart).

Next steps#