Camera-Offset | Project Tango - unity3d

I am developing an augmented reality app for Project Tango using Unity3d.
Since I want to have virtual object interact with the real world, I use the Meshing with Physics scene from the examples as my basis and placed the Tango AR Camera prefab inside of the Tango Delta Camera (at the relative position (0,0,0)).
I found out, that I have to rotate the AR Camera up by about 17deg, so the Dynamic mesh matches the room, however there is still a significant offset to the live preview from the camera.
I was wondering, if anyone who had to deal with this before could share his solution to aligning the Dynamic Mesh with the real world.
How can I align the virtual world with the camera image?

I'm having similar issues. It looks like this is related to a couple of previously-answered questions:
Point cloud rendered only partially
Point Cloud Unity example only renders points for the upper half of display
You need to take into account the color camera offset from the device origin, which requires you to get the color camera pose relative to the device. You can't do this directly, but you can get the device in the IMU frame, and also the color camera in the IMU frame, to work out the color camera in the device frame. The links above show example code.
You should be looking at something like (in unity coordinates) a (0.061, 0.004, -0.001) offset and a 13 degree rotation up around the x axis.
When I try to use the examples, I get broken rotations, so take these numbers with a pinch of salt. I'm also seeing small rotations around y and z, which don't match with what I'd expect.

Related

World to Cube projection Unity

That's the setting:
I have 2 cameras in the game scene. The game must be played in a room with screens on frontal wall and on the floor. To be able to test it I just recreated the 2 screens in Unity. The goal is to make the game immersive, creating the correct illusion as the image on the left.
What I've tried so far (and it kinda worked as you can see from the screenshot) is:
Camera0: goes directly in the frontal display.
Camera1: I created a post processing effect that deforms the output texture to create the correct perspective illusion.
The problem:
The fact that I'm basically working over a texture creates some blurry effect on the borders, because the pixel density is not the same in start and deformed image.
I think the best approach would be to make the deforming transformation happen on the projection matrix of Camera1 instead. But I just failed. Have you any idea on how to approach this problem correctly?
You can let your perspective cameras do the work for you.
Set the fov of the floor camera so that it shows only as much as will fit on the screen.
Then, have the cameras at the same position.
Finally, have the floor camera rotated on the +x axis by half of the sum the fov of both cameras. For example, if the wall camera is fov 80º and the floor fov is 40º, set the floor camera to be rotated by 60º along the x axis.
This will guarantee that the view of the cameras do not overlap, and they will have the correct projection along their surfaces to create the desired illusion.

track real object movements via vofuria and unity ignoring camera movements

I am developing an augmented reality application that tracks an object via camera (real object, using Vuforia), my aim is to detect the distance it pass.
I am using unity + Vuforia.
For each frame, I calculate the distance between the first position and the current position (Vector calculating).
But I got wrong position/s details, and camera movements affect the result.
(I don't want to take the camera offset in account)
any solution?
for more clearing I want to implement this experience: (video):
https://youtu.be/-c5GiXuATh4
From the comments and the question i understood problem is using camera as origin. This means at all frames of your application camera will be origin and the position of all trackables will be calculated relative to camera. Therefore, even though if you do not move your target, it's position will change because of camera movement.
To eliminate this problem i would recommend using extended tracking. This will minimize the impact of camera movement to position of your target. You can try and test this by adding a trail renderer to your image and you will see your image will stay at a certain position regardless of camera movement.

Can Vuforia track spatial location when using targetless device tracking?

I am trying to wrap my head around Vuforia's capabilities. I want to make an app which lets me place a 3D object into a camera view and have that 3D object stick to the world. I've been learning how to use Vuforia in Unity3D, and Vuforia seems to be slightly capable of this, but is severely limited by its craving for "Targets". It doesn't seem to be able to do much if I don't give it some sort of target.
One workaround I've found is to set the ARCamera's World Center Mode to DEVICE_TRACKING. This seems to let me place a 3D object into the world (in Unity) and have this object overlay into the camera feed, almost making it seem like it's anhcored to the real world. This doesn't work perfectly though: it tracks properly when I angle the device up/down/left/right (rotation), but it does not seem to track the device's translational motion; that is, when I move the device forward/back/left/right, the overlaid object doesn't get closer/farther nor does it rotate as I move around it.
Is it possible to get this sort of tracking out of Vuforia, or am I better off switching to something like Google Tango?
The difficulty with setting World Center Mode to CAMERA in Vuforia is that apparently 3D objects rotate around the camera based on its accelerometer/gyroscope changes. This doesn't allow for objects to be anchored to the environment. Instead they follow with the camera.
Kudan is a good markerless tracking option.

Using PointCloud Prefab on Unity 3D

I tryed to implement the "Measure It" app on Unity 3D. I started with the PointCloud example scene downloaded on tango's website.
My problem is, when i look in 1st Person view, the point cloud don't fiel the screen, and when i look in 3rd Person I can see the point outside the Unity Camera FOV.
I don't see this problem on the Explorer app, but it looks to be made in Java so I think it's a Unity compatibility problem.
Does someone have the same problem, or a solution?
Unity 3D 5.1.1
Google Tango urquhart
Sorry for my poor english,
Regards.
EDIT :
It looks like the ExperimentalAugmentedReality scene is using the point cloud to place markers in real world, and this point cloud is right in front of the camera. I don't see any script difference between them so i don't understand why it works. If you've any idea.
I think it makes sense to divide you question into two parts.
Why the points are not filling in the screen in the point cloud example.
In order to make the points to fill in the first person view camera, the render camera's FOV needs to match the physical depth camera's FOV. In the point cloud example, I believe Tango is just using the default Unity camera's FOV, that's why you saw the points is not filling the screen(render camera).
In the third person camera view, the frustum is just a visual representation of the device movement. It doesn't indicate the FOV or any camera intrinsics of the device. For the visualization purpose, Tango explore might specifically matched the camera frustum size to the actual camera FOV, but that's not guaranteed to be 100% accurate.
Why the AR example works.
In the AR example, we must set the virtual render camera's FOV to match the physical camera's FOV, otherwise the AR view will be off. On the Tango hardware, the color camera and depth camera are the same camera sensor, so they shared a same FOV. That's why the AR example works.

unity3d - how to control the movement of the main Camera in Unity3d

I am trying to make an mobile application that contains AR(Augumented Reality)-Mode using Unity3D. So I have connected my mobile device with my unity3d program, and the camera works fine. But when move the mobile device, the main camera inside unity program does not move the same orbit that the mobile device moves. Does any one know how to change or control the orbit of the main Camera in unity3d?
This could be happening due to a number of reasons. It could be due to non centered pivots, or coordinate systems for example.
Could you please specify which AR system are you using? As a side note, at work we recently had a project involving Unity3d and Metaio and it was a nightmare to bend the system to do what we needed, specially when we needed to do a lot of object positioning based on the local coordinate system.
When you refer to the orbit of the camera, I imagine it could be that the pivot of the camera is somehow offset and the camera is rotating around that offset. Or maybe that the camera is a child of the actual Game Object that is controlled by the AR system, in which case this parent node acts as a pivot to the camera.
In the picture below you can see that the camera is away from that center point and when it rotates it does it based on that center point, in other words the camera always tries to look at that center point and it gives that feeling of "orbiting" when it moves.
Here's the link to the image (I can't post pictures yet on this forum -.- )
http://i.stack.imgur.com/fIcY2.png