I am experimenting with overlaying augmented reality objects over a pass-through image from the rear camera in Unity.
Has anyone experimented with overlaying objects with accurate tracking? I've tweaked the movement scale to get somewhat decent results but rotation is still not accurate and drift is a big issue.
I've had good luck with the augmented reality sample that ships with the latest tango. in my experience it does work the way you speculated where if you add items to the unity scene they are synced to motion detected by the device.
I believe the tracking and syncing function have improved since you asked this question originally because I've noticed an improvement since I got my tango devkit a month or so ago. there was an update a week or so later, with an immediate improvement.
I have found that some scenes track better than others, it seems to help for there to be additional scenery for it to track. in my workspace, a fairly cluttered apartment, it tracks well but in the neighboring identical apartment unit which is currently vacant and empty, it does not track as well. that could also be a product of the blinds hanging up in my unit that are not hanging up in the vacant unit, filtering out additional infrared.
I'm experimenting with placing 3D objects over the real time input from the Tango color camera.
One problem here is that the hardware color camera 'point' in a (strange) direction. I wasn't able to get the direction vector from the api until now. Your virtual camera for rendering the scene needs this rotation to render 3D objects properly.
There are augmented reality examples of Tango's Unity plugin:
https://developers.google.com/tango/apis/unity/unity-simple-ar
They solve this problem with a matrix that rotates the 3d camera.
It can be found in the Unity script "TangoARPoseController" (C#) that, when attached to a unity camera, rotates it so that it looks at the scene in the right direction. The matrix is obtained in the method "SetCameraExtrinsics" of that script.
Unfortunately, when I apply the matrix to my unity scene it does not produce a perfect overlay (actually it's quiet bad). But I have other sources of position input which may be the problem here.
However, until now I'm not sure if the matrix used in the examples is good enough for accurate ar overlays. Maybe it is just suitable for demonstration purposes. But it should be a good starting point for further investigation.
Are we talking about displaying the 'webcam' in the background as opposed to a skybox ?
Take a look at my GhostHunter repo. It includes a shader and a script for displaying the rear facing camera 'behind' the gameplay objects (like the skybox). It should be useable with Tango and it is better than the 'display on a mesh' technique I`ve seen others used.
https://github.com/NVentimiglia/Augmented-Reality-Ghost-Hunter
Related
I'm using unity 2018.4.14f1 personal (I don't use 2019 or 2020 because it lags my computer)
I'm using the Unity Standard Assets Player Prefab and Cinemachine Freelook for the camera. I have some water, and when my player walks into it, its fine. However, when the camera comes into the water, it stops rendering the water. Is there anyway I can fix it?
Update: I've somewhat got it working, however its hollow when your inside. Is there anyway to fix that?
Video : https://easyupload.io/2b0p3a
(I'm quite a noob so if you need any screenshots please ask.)
The problem here is that the water will only rendered when looking from the outside as the normalized are modeled so. The program renders outs objects that it thinks is not in view. You can load the model into a 3d program and then copy and invert the model to allow your camera to see the water, or I believe there are some shader option to stop this optimization. You can also look in this Reddit thread.
I built an apk using the HelloAR scene (which is provided with ARcore package). The app is only detecting Horizontal surface like table and creates it's own semi-transparent plane over it. When I moved my phone around a bottle, the app again, only created a horizontal plane cutting through the bottle. I expected ARCore to create planes along the bottle as I move my phone around, like polygons in a mesh.
Another scenario is, I placed 2 books on the floor, and each of them have different thickness. But the HelloAR app creates only one semi-transparent horizontal surface over the thicker book, instead of creating two surfaces (one for each book).
What is going wrong here? How can I fix it and make the HelloAR app work more precisely? Please help.
Software: Unity v2018.2,
ARcore v1.11.0
ARCore generates an approximate point cloud using a soft movement of the device to identify the featured points, this points are detected by contrast in the different shapes, if you use your application in test mode in unity you can see how the points are placed in your empty scene.
Once the program has enough points at the "same height" (I don't know the exact precision), it generates the plane that you can see, but it won't detect planes separated by a difference of 5cm or even more distance.
If you want to know the approximate accuracy of the app, test it with unity and make a script to capture the generated points that have been used to generate the planes, then check the Y difference to see which is the tolerance distance.
Okay so Vuforia is currently one of the leading SDKs for augmented reality providing a wide area of detection options (Images, Ground, Point, 3D objects, ...)
So regarding your question about detecting a bottle I would most certainly use the 3D model detection feature. You can read the official docs here.
You need to first generate an approximate of the object in a 3d modeling software and the use their program to generate the detection model. Then you put this in Unity and setup the detection. (no coding needed)
I have some experience with this kind of detection. I used it to detect a large 2mx2m scale model of an electric vehicle. It works great, you can walk around it and it tracks it through and through. You can see a short official demo here
Hope it helped to explain this in short!
I'm working on a project for an exhibition where an AR scene is supposed to be layered on top of a 3D printed object. Visitors will be given a device with the application pre-installed. Various objects should be seen around / on top of the exhibit, so the precision of tracking is quite important.
We're using Unity to render the scene, this is not something that can be changed as we're already well into development. However, we're somewhat flexible on the technology we use to recognize the 3D object to position the AR camera.
So far we've been using Vuforia. The 3D target feature didn't scan our object very well, so we're resorting to printing 2D markers and placing them on the table that the exhibit sits on. The tracking is precise enough, the downside is that the scene disappears whenever the marker is lost, e.g. when the user tries to get a closer look at something.
Now we've recently gotten our hands on a Lenovo Phab 2 pro and are trying to figure out if Tango can improve on this solution. If I understand correctly, the advantage of Tango is that we can use its internal sensors and motion tracking to estimate its trajectory, so even when the marker is lost it will continue to render the scene very accurately, and then do some drift correction once the marker is reacquired. Unfortunately, I can't find any tutorials on how to localize the marker in the first place.
Has anyone used Tango for 3D marker tracking before? I had a look at the Area Learning example included in the Unity plugin, by letting it scan our exhibit and table in a mostly featureless room. It does recognize the object in the correct orientation even when it is moved to a different location, however the scene it always off by a few centimeters, which is not precise enough for our purposes. There is also a 2D marker detection API for Tango, but it looks like it only works with QR codes or AR tags (like this one), not arbitrary images like Vuforia.
Is what we're trying to achieve possible with Tango? Thanks in advance for any suggestions.
Option A) Sticking with Vuforia.
As Hristo points out, Your marker loss problem should be fixable with Extended Tracking. This sounds definitely worth testing.
Option B) Tango
Tango doesn't natively support other markers than the ARTags and QRCodes.
It also doesn't support the Area Learnt scene moving (much). If your 3DPrinted objects stayed stationary you could scan an ADF and should have good quality tracking. If all the objects stay still you should have a little but not too much drift.
However, if you are moving those 3D Printed objects, it will definitely throw that tracking off. So moving objects shouldn't be part of the scanned scene.
You could make an ADF Scan without the 3D objects present to track the users position, and then track the 3D printed objects with ARMarkers using Tangos ARMarker detection. (unsure - is that what you tried already?) . If that approach doesn't work, I think your only Tango option is to add more features/lighting etc.. to the space to make the tracking more solid.
Overall, Natural Feature tracking by Vuforia (or Marker tracking for robustness) sounds more suited to what I think your project is doing, as users will mostly be looking at the ARTag/NFT objects. However, if it's robustness is not up to scratch, Tango could provide a similar solution.
All the Tango Apps and Demos I have seen so far have one major limitation: 3D-Objects are always "on top" of the real world camera image. They are placed correctly in 3D space but a real object in front of the virtual object will not overlap it!
Question:
Is it possible to mask 3D objects or parts of them in realtime by real world objects in front of them?
In theory the 3D data deliverd by Tango sensors should be sufficient to do this. But I wonder if anyone has done it before or if there might be performance limitations that make this impossible? Thanks for your advice!
One approach is to use the 3D Reconstruction library (search "Unity How-to Guide: Meshing with Color") to pre-scan the environment, and then use this model to provide depth data when rendering the AR scene. Here's a video of an AR game that appears to use this technique. It's not perfect for sure, but it does sorta work.
This questions has been asked before.
I am tring to do occlusion with Google Tango in Unity.
What I want is pretty simple to understand: when there is a real object in front of a virtual object, the virtual object is hidden (or rendered differently)
The perfect result would be like it is in this impressive video I found: https://www.youtube.com/watch?v=EpDhaM7ZhZs .
I already tried the "Enable occlusion" option of the Tango Camera and I am not so happy with the results (it is not accurate and not real time as it is based on mesh reconstruction from the point cloud).
If you have hints, tips or ideas about how to achieve this (like in the video), that would be awesome!
Occlusion is still a very experimental feature on Tango. The problem is that it's very hard to do occlusion with high fidelity and high performance, here's couple of ideas on how to achieve it using different method:
Use 3D reconstruction.
Tango does provide functionalities to construct 3D meshes from point cloud, you can find sample code from Tango sample code repository (C, Java, Unity). If you have a world that is pre-scanned, you can essentially use that mesh data to occluded virtual object.
Run time up-sampling depth image.
You can also project all point clouds on to an image plane, up-sample it, and use the image as a depth buffer for rendering. This is what ARScreen occlusion is using in TangoUnitySDK. Due to the limitation of Tango depth sensing hardware, the result quality is not very ideal, and it will not work if all physical objects are far away(beyond 4 meters) from the device.