Log in or register to post comments

Image Target detected at angle causing physics based objects to fall

July 22, 2020 - 2:01pm #1

Good Day All,

 

I'm having a hard time figuring out what could be the cause of my Image Target issue. I am using Unity version 2019.3.15f1 and Vuforia 9.3.3. I have a couple of issues, one issue is present when detecting an image target with Camera: Vuforia Behaviour component World Center Mode set to  DEVICE. When I am in this mode, my image targets and child objects appear, although they seem to be anchored to the camera and follow the angle and position of that physical camera. This is causing my physics based child objects to fall off the image target once detected with gravity activated. Previously I think I had this component set to "FIRST_TARGET" in which all the image targets remained at their World position and the camera revolved around the image target. This behavior was working until my recent upgrade to 9.2.8 (About a month back) and in hope to resolve my issue I updated to 9.3.3 7/22/20.

The other issue I am having is when I set this Vuforia Behaviour camera setting back to "FIRST_TARGET", all the child objects of the Image Target render in the scene view where the image target position is but they do not appear in the game view via the scene camera. This leaves me stuck and confused as the game objects are responding as this should in the place I expect however, not seeing them on screen is a bummer. The only way I can see my child objects is when my World Center Mode is set to DEVICE.

 

Please advise,

 

TruAmbition
Joined:
February 25, 2018
Posts: 4
Top

Image Target detected at angle causing physics based objects to fall

June 17, 2021 - 4:37am #5

Hi, 

My understanding of your issue as follows: The image Target is detected and when you tilt the camera, the Image Target also tilts and the balls falls down. 

Image Target should not tilt based on the device, are you by any chance having the image Target a child of the AR Camera? Un-parenting it, should address this. 

Thank you.

Vuforia Engine Support

mcotora
Joined:
March 15, 2019
Posts: 1676
Top

Image Target detected at angle causing physics based objects to fall

June 5, 2021 - 6:18pm #4

revisiting this experience again, please advise as to how I return to how Vurforia use to detect targets so that my gravity is relative to the card and not the angle of the camera?

 

My child objects only show up when I use World Center Mode Device, if I use World Center Mode First_Target, the child objects act as expected in the editor window but are not shown in the game view as they are not in the same position in world space as the card itself.

please advise as this is really preventing us from deploying fun physics based experiences that are based on the cards rotation, not the rotation of the camera. 

TruAmbition
Joined:
February 25, 2018
Posts: 4
Top

Image Target detected at angle causing physics based objects to fall

August 20, 2020 - 12:09am #3

This solution will only keep the objects within the box collider. Is there a way to get back to the legacy style where the image target is the center point so objects don't tilt with the orientation of the camera?

TruAmbition
Joined:
February 25, 2018
Posts: 4
Top

Image Target detected at angle causing physics based objects to fall

July 29, 2020 - 5:24am #2

Hi,

Q1: I've quickly tested the behavior and can confirm that using Rigidbody on the child of the IT will make them fall down.

You will need to add a box colider on the IT, adjust the size accordingly. This should prevent your child GameObjects from falling.

Q2: This would be the normal behavior, you should see only the camera with a videofeed.

Thank you.

Vuforia Engine Support

mcotora
Joined:
March 15, 2019
Posts: 1676
Top
Log in or register to post comments