# \#detection **URL:** https://forums.unrealengine.com/tag/detection/4258.md [Latest](https://forums.unrealengine.com/latest.md) · [Categories](https://forums.unrealengine.com/categories.md) · [Tags](https://forums.unrealengine.com/tags.md) --- ## [AI Perception inconsistent behavior.](https://forums.unrealengine.com/t/ai-perception-inconsistent-behavior/2672924)
**Author:** [@Extrahdmi](https://forums.unrealengine.com/u/Extrahdmi)\ **Replies:** 2\ **Last updated:** [November 8, 2025, 11:25am UTC](https://forums.unrealengine.com/t/ai-perception-inconsistent-behavior/2672924 "2025-11-08T11:25:20Z")
I’m confused by unexpected AI Perception behavior. Actors derived from a single class have identical AIPerceptionStimuliSource settings. So, These should detect these classes equally, but in reality it selectively detec… --- ## [Problem with Line Trace/Sphere Trace Fires in All Clients??](https://forums.unrealengine.com/t/problem-with-line-trace-sphere-trace-fires-in-all-clients/2311700)
**Author:** [@RAT\_Official](https://forums.unrealengine.com/u/RAT_Official)\ **Replies:** 1\ **Last updated:** [January 31, 2025, 12:54pm UTC](https://forums.unrealengine.com/t/problem-with-line-trace-sphere-trace-fires-in-all-clients/2311700 "2025-01-31T12:54:39Z")
Even though, i am running Custom Event “Run on owning Client”… it somehow runs on both other clients and server Somehow, other clients interact with other clients?? i mean in a way : Server : Works normal, only … --- ## [Spawn Actor - Not detecting collision correctly](https://forums.unrealengine.com/t/spawn-actor-not-detecting-collision-correctly/380967)
**Author:** [@ReckDev](https://forums.unrealengine.com/u/ReckDev)\ **Replies:** 4\ **Last updated:** [May 19, 2024, 9:42pm UTC](https://forums.unrealengine.com/t/spawn-actor-not-detecting-collision-correctly/380967 "2024-05-19T21:42:24Z")
I have been using Spawn Actor to spawn an actor at a random location inside a set area. All the spawning works fine but they were spawning and overlapping so I decided to use the “Collision Handling Override” on the Spaw… --- ## [Making a hovering ship that can follow hill slopes](https://forums.unrealengine.com/t/making-a-hovering-ship-that-can-follow-hill-slopes/343313)
**Author:** [@VoidGoat](https://forums.unrealengine.com/u/VoidGoat)\ **Replies:** 4\ **Last updated:** [December 4, 2022, 11:02pm UTC](https://forums.unrealengine.com/t/making-a-hovering-ship-that-can-follow-hill-slopes/343313 "2022-12-04T23:02:58Z")
I have created a ship using blueprints that will hover above the ground. However I can’t figure out how to get it to fly over hills and slopes. It is set up right now to move up more when it gets closer than its desired … --- ## [Detect if given actors are visible in shape-part of the screen](https://forums.unrealengine.com/t/detect-if-given-actors-are-visible-in-shape-part-of-the-screen/499487)
**Author:** [@dominique57](https://forums.unrealengine.com/u/dominique57)\ **Replies:** 10\ **Last updated:** [February 18, 2022, 5:21pm UTC](https://forums.unrealengine.com/t/detect-if-given-actors-are-visible-in-shape-part-of-the-screen/499487 "2022-02-18T17:21:30Z")
Hello there, very new programmer with unreal engine here ! First of all, I’m sorry if it isn’t in the correct category for this question, and since I am prototyping it in blueprint I thought it would be the most adequat… --- ## [Looking for Help with Custom Object Culling Tool](https://forums.unrealengine.com/t/looking-for-help-with-custom-object-culling-tool/481602)
**Author:** [@Uj6D76b95mR3W](https://forums.unrealengine.com/u/Uj6D76b95mR3W)\ **Replies:** 0\ **Last updated:** [April 8, 2021, 2:24pm UTC](https://forums.unrealengine.com/t/looking-for-help-with-custom-object-culling-tool/481602 "2021-04-08T14:24:17Z")
Hello! I currently work for a small indie group and they have an in-house culling tool to hide parts of a structure for people to look inside. Ive been pushing for a change but at the moment that will more than likely n… --- ## [Detecting pixel colors inside images](https://forums.unrealengine.com/t/detecting-pixel-colors-inside-images/476366)
**Author:** [@BladeDev](https://forums.unrealengine.com/u/BladeDev)\ **Replies:** 3\ **Last updated:** [January 15, 2021, 4:35pm UTC](https://forums.unrealengine.com/t/detecting-pixel-colors-inside-images/476366 "2021-01-15T16:35:50Z")
Hello, I require some assistance on this issue. I have a 32x32 image variable, and I need a way to get the colour value of each pixel. I never coded anything like this, so I have no clue how to execute this. I would ap… --- ## [Add new collision (for overlap check) for each instanced mesh?](https://forums.unrealengine.com/t/add-new-collision-for-overlap-check-for-each-instanced-mesh/476877)
**Author:** [@Lino\_Drieghe](https://forums.unrealengine.com/u/Lino_Drieghe)\ **Replies:** 3\ **Last updated:** [January 7, 2021, 8:41am UTC](https://forums.unrealengine.com/t/add-new-collision-for-overlap-check-for-each-instanced-mesh/476877 "2021-01-07T08:41:02Z")
Hello, I’m currently spawning trees as instanced meshes. I have at the moment a simple collision set up on my SM\_Tree to avoid walking through it. I’m looking for a way to check if actor’s (villagers in RTS-game) are i… --- ## [The detection system. Visibility from the hill.](https://forums.unrealengine.com/t/the-detection-system-visibility-from-the-hill/475148)
**Author:** [@OverkillBY](https://forums.unrealengine.com/u/OverkillBY)\ **Replies:** 1\ **Last updated:** [November 29, 2020, 12:31pm UTC](https://forums.unrealengine.com/t/the-detection-system-visibility-from-the-hill/475148 "2020-11-29T12:31:04Z")
Designing a vision system for characters. This works well until the character is at the top. I can finish the rays so that I get something like a cone with a convex base. But I don’t think this solution is elegan… --- ## [Edge detection](https://forums.unrealengine.com/t/edge-detection/294605)
**Author:** [@anonymous\_user\_4bbf8dca](https://forums.unrealengine.com/u/anonymous_user_4bbf8dca)\ **Replies:** 4\ **Last updated:** [November 11, 2019, 5:19pm UTC](https://forums.unrealengine.com/t/edge-detection/294605 "2019-11-11T17:19:20Z")
This is getting a bit hard, but since Im a beginner in UE4 im asking for some help. ¿How Do I detect a gap or an edge of a wall? I already did it with walls, just a single sphere trace, but now what with the edges?. Im … --- ## [How to detect which motion controller is connected](https://forums.unrealengine.com/t/how-to-detect-which-motion-controller-is-connected/452738)
**Author:** [@anonymous\_user\_b30f6442](https://forums.unrealengine.com/u/anonymous_user_b30f6442)\ **Replies:** 1\ **Last updated:** [July 24, 2019, 1:50pm UTC](https://forums.unrealengine.com/t/how-to-detect-which-motion-controller-is-connected/452738 "2019-07-24T13:50:55Z")
Hey all So unreal has a nifty ‘Get HMD Device Name’ node that returns which headset the user is wearing. From there I am able to change the controls to work with Oculus Touch or Vive wand controllers. But now with the i… --- ## [GamePad Not Detected By Ue4](https://forums.unrealengine.com/t/gamepad-not-detected-by-ue4/323635)
**Author:** [@anon54496231](https://forums.unrealengine.com/u/anon54496231)\ **Replies:** 2\ **Last updated:** [November 11, 2018, 7:14pm UTC](https://forums.unrealengine.com/t/gamepad-not-detected-by-ue4/323635 "2018-11-11T19:14:38Z")
GamePad which is cheap generic type works fine on system in other apps and games but is not detected in ue4(4.7 and 4.8), is there some setting i am missing or does only an xbox controller work, these seem to work fine f… --- ## [Tron Effect on Static Meshes (Edge Detection)](https://forums.unrealengine.com/t/tron-effect-on-static-meshes-edge-detection/349599)
**Author:** [@kickassitus](https://forums.unrealengine.com/u/kickassitus)\ **Replies:** 3\ **Last updated:** [October 17, 2018, 1:13am UTC](https://forums.unrealengine.com/t/tron-effect-on-static-meshes-edge-detection/349599 "2018-10-17T01:13:09Z")
Hi, I’ve been working with a Tron Material (Tut’s Here: watch?v=KHiZfy5OlO8) and I’ve tried applying it to a Static Mesh which I created in Maya (See Below). Now, despite my strong amount of hope and believing, the obv… --- ## [Detect light perceived by player camera](https://forums.unrealengine.com/t/detect-light-perceived-by-player-camera/433061)
**Author:** [@palinoia\_gamedev](https://forums.unrealengine.com/u/palinoia_gamedev)\ **Replies:** 2\ **Last updated:** [September 4, 2018, 2:30pm UTC](https://forums.unrealengine.com/t/detect-light-perceived-by-player-camera/433061 "2018-09-04T14:30:49Z")
Is there a way to detect the sunlight intensity at a given spot? I want my character to look away when facing the sun or another intense light source but couldn’t find a good approach for this yet. --- ## [SweepMultiByChannel Returns same Actor multiple times](https://forums.unrealengine.com/t/sweepmultibychannel-returns-same-actor-multiple-times/425614)
**Author:** [@PlayerOneBo](https://forums.unrealengine.com/u/PlayerOneBo)\ **Replies:** 5\ **Last updated:** [September 3, 2018, 8:15pm UTC](https://forums.unrealengine.com/t/sweepmultibychannel-returns-same-actor-multiple-times/425614 "2018-09-03T20:15:55Z")
Hello, I’m having a problem using the function SweepMultiByChannel. I am creating an Sphere using SweepMultiByChannel to detect nearby actors within an specific radius. When I place a pawn actor with basic mesh, collisio… --- ## [Is there anyway I can use the lines that project from a spotlight when adjusting the attenuation radius to detect collision?](https://forums.unrealengine.com/t/is-there-anyway-i-can-use-the-lines-that-project-from-a-spotlight-when-adjusting-the-attenuation-radius-to-detect-collision/403351)
**Author:** [@RagingPanic](https://forums.unrealengine.com/u/RagingPanic)\ **Replies:** 2\ **Last updated:** [August 31, 2017, 4:45pm UTC](https://forums.unrealengine.com/t/is-there-anyway-i-can-use-the-lines-that-project-from-a-spotlight-when-adjusting-the-attenuation-radius-to-detect-collision/403351 "2017-08-31T16:45:52Z")
I would like to use these lines to detect collision with the player for a stealth game. I would be open to any C++ solutions or even a way to re-create these lines as vectors or traces to detect collision with the env… --- ## [Collisions with Static Meshes](https://forums.unrealengine.com/t/collisions-with-static-meshes/329361)
**Author:** [@LCCoombs\_1](https://forums.unrealengine.com/u/LCCoombs_1)\ **Replies:** 1\ **Last updated:** [July 17, 2017, 8:25pm UTC](https://forums.unrealengine.com/t/collisions-with-static-meshes/329361 "2017-07-17T20:25:59Z")
Hey now, So ive been Making a Two stick shooter and ive created a ship that shoot projectiles, Ive began to create Enemies but they do not detect/react to collisions from the Projectiles from the player. For example i h… --- ## [Detecting axis if user dragging mouse](https://forums.unrealengine.com/t/detecting-axis-if-user-dragging-mouse/390955)
**Author:** [@Khubur](https://forums.unrealengine.com/u/Khubur)\ **Replies:** 2\ **Last updated:** [April 18, 2017, 3:04pm UTC](https://forums.unrealengine.com/t/detecting-axis-if-user-dragging-mouse/390955 "2017-04-18T15:04:17Z")
Hey, there is any detection function or something like for if user is pressing left button and dragging mouse. How do I do detect it? I want to rotate right if user is pressing and rotating to right. ( I have rotation fu… --- ## [AI Perception Component not working as expected](https://forums.unrealengine.com/t/ai-perception-component-not-working-as-expected/315424)
**Author:** [@Stormrage256](https://forums.unrealengine.com/u/Stormrage256)\ **Replies:** 3\ **Last updated:** [April 6, 2017, 12:33pm UTC](https://forums.unrealengine.com/t/ai-perception-component-not-working-as-expected/315424 "2017-04-06T12:33:31Z")
Hi, I just started working on AI Perception component. I have a base character blueprint which is the parent of all units from player team. At Event begin play, I’m making it register perception stimuli source. I add… --- ## [OnBeginCursorOver - detect even if obscured?](https://forums.unrealengine.com/t/onbegincursorover-detect-even-if-obscured/337601)
**Author:** [@Slavq](https://forums.unrealengine.com/u/Slavq)\ **Replies:** 3\ **Last updated:** [April 6, 2017, 12:27pm UTC](https://forums.unrealengine.com/t/onbegincursorover-detect-even-if-obscured/337601 "2017-04-06T12:27:23Z")
Is it possible to detect OnBeginCursorOver on a collider that is e.g. behind a wall? --- ## [Detecting what actor touches](https://forums.unrealengine.com/t/detecting-what-actor-touches/386473)
**Author:** [@anonymous\_user\_e9b03a28](https://forums.unrealengine.com/u/anonymous_user_e9b03a28)\ **Replies:** 1\ **Last updated:** [February 28, 2017, 11:51am UTC](https://forums.unrealengine.com/t/detecting-what-actor-touches/386473 "2017-02-28T11:51:42Z")
I want to make an ingot that knows which fire it touched. --- ## [AIPerception : how to use "detection by affiliation"](https://forums.unrealengine.com/t/aiperception-how-to-use-detection-by-affiliation/329281)
**Author:** [@zigziglagirafe](https://forums.unrealengine.com/u/zigziglagirafe)\ **Replies:** 6\ **Last updated:** [December 18, 2016, 1:59am UTC](https://forums.unrealengine.com/t/aiperception-how-to-use-detection-by-affiliation/329281 "2016-12-18T01:59:17Z")
Hi, How do we use “detection by affiliation” on AIPerception component please? It proposes “detect ennemy” / “neutral” / “friendly”, but how am i supposed to tag an actor as one of this ? Is there an interface to impl… --- ## [How do I deal damage ONLY when collision boxes have overlapped for a certain amount of time?](https://forums.unrealengine.com/t/how-do-i-deal-damage-only-when-collision-boxes-have-overlapped-for-a-certain-amount-of-time/376019)
**Author:** [@anonymous\_user\_68623ae7](https://forums.unrealengine.com/u/anonymous_user_68623ae7)\ **Replies:** 5\ **Last updated:** [November 11, 2016, 11:29pm UTC](https://forums.unrealengine.com/t/how-do-i-deal-damage-only-when-collision-boxes-have-overlapped-for-a-certain-amount-of-time/376019 "2016-11-11T23:29:39Z")
I have collision damage working fine , but I want the damage to only be dealt when the players and enemies collision boxes over lap for 2 seconds. (If my player escapes the enemies collision box before two seconds he tak… --- ## [AFK detection](https://forums.unrealengine.com/t/afk-detection/345137)
**Author:** [@anonymous\_user\_c44ea37c](https://forums.unrealengine.com/u/anonymous_user_c44ea37c)\ **Replies:** 2\ **Last updated:** [January 24, 2016, 7:40pm UTC](https://forums.unrealengine.com/t/afk-detection/345137 "2016-01-24T19:40:21Z")
Hi, I am having a hard time devising a “away from keyboard” detection for a single player game which originates from the third person template. basically I have tried storing the player’s location, followed by a retrigg… --- ## [What is better: collison box or line trace for RPG?](https://forums.unrealengine.com/t/what-is-better-collison-box-or-line-trace-for-rpg/342311)
**Author:** [@Taratus](https://forums.unrealengine.com/u/Taratus)\ **Replies:** 1\ **Last updated:** [December 28, 2015, 8:10pm UTC](https://forums.unrealengine.com/t/what-is-better-collison-box-or-line-trace-for-rpg/342311 "2015-12-28T20:10:25Z")
Hello I need to get information about items lying on the ground and NPC’s standing in front of my pawn. Should I use collison boxes, but I think they are not blocked by walls and that’s bad or line traces with event tick… --- ## [How to make HUD bob? (and more.)](https://forums.unrealengine.com/t/how-to-make-hud-bob-and-more/342487)
**Author:** [@IceCubeCat](https://forums.unrealengine.com/u/IceCubeCat)\ **Replies:** 1\ **Last updated:** [December 27, 2015, 9:42pm UTC](https://forums.unrealengine.com/t/how-to-make-hud-bob-and-more/342487 "2015-12-27T21:42:09Z")
Hey guys, have a few questions for my third person shooter. I have a HUD, and I want to make it bob when my character moves. So here’s the questions I need answered. How do I detect movement and set it as a variable? (… --- ## [Unreal Engine not detecting Oculus /Ubuntu/](https://forums.unrealengine.com/t/unreal-engine-not-detecting-oculus-ubuntu/341166)
**Author:** [@anonymous\_user\_87acc680](https://forums.unrealengine.com/u/anonymous_user_87acc680)\ **Replies:** 0\ **Last updated:** [December 11, 2015, 2:02pm UTC](https://forums.unrealengine.com/t/unreal-engine-not-detecting-oculus-ubuntu/341166 "2015-12-11T14:02:02Z")
Hello, I am working on my bachelor thesis and would like to create extended positional tracking based on RGB camera attached to Oculus (infinite positional tracking). I have algorithms already up and running and would l… --- ## [Perception is inconsistent?](https://forums.unrealengine.com/t/perception-is-inconsistent/339458)
**Author:** [@Gmi](https://forums.unrealengine.com/u/Gmi)\ **Replies:** 0\ **Last updated:** [November 23, 2015, 6:51pm UTC](https://forums.unrealengine.com/t/perception-is-inconsistent/339458 "2015-11-23T18:51:48Z")
I have a problem where my perception component does not seem to be updating correctly. With the debug tools on, I can see that it does notice my AI, but for some reason it’s not updating my blueprint correctly. screensh… --- ## [HTML5 Supported Browser Detector](https://forums.unrealengine.com/t/html5-supported-browser-detector/332171)
**Author:** [@asmrpuppy](https://forums.unrealengine.com/u/asmrpuppy)\ **Replies:** 4\ **Last updated:** [October 1, 2015, 8:53pm UTC](https://forums.unrealengine.com/t/html5-supported-browser-detector/332171 "2015-10-01T20:53:36Z")
Hi Epic/Community, I’m currently loving HTML5 development with UE, but I’ve hit a snag. I want to, similar to the Tappy Chicken HTML app, notify the if they have an unsupported browser. I wonder if there is a JavaScr… --- ## [How to detect where's the hit coming?](https://forums.unrealengine.com/t/how-to-detect-wheres-the-hit-coming/333635)
**Author:** [@anonymous\_user\_4b715534](https://forums.unrealengine.com/u/anonymous_user_4b715534)\ **Replies:** 2\ **Last updated:** [September 28, 2015, 8:20pm UTC](https://forums.unrealengine.com/t/how-to-detect-wheres-the-hit-coming/333635 "2015-09-28T20:20:20Z")
Hello… On a Third Person game, when the player takes one melee hit, he have one reaction. But if this hit come from the back, or the side of the player, the reaction is different… How can I detect where is the hit comin… [Next page](https://forums.unrealengine.com/tag/detection/4258.md?match_all_tags=true&page=1&tags%5B%5D=detection)