Added FeatheredPlanes scene from samples to my project.
The problem is: when the content
https://gyazo.com/685b86f10b01e734dac14d57ee7a022e
is per-defined (set the cube or any object before building) - everything works fine.
When the object is set dynamically, my object is loading from the server and then is setting to the "content", then after placing it to the virtual plane - it starts to move if i move my camera.
The problem was model's pivot point.
It was at the center of the model, and all i had to do, is to offset the model, so the bottom part of the model is leveled with the floor.
Related
How to Match a reference point in 2 different AR scenes by position and rotation?
Here are some details about my project:
I have 2 scenes: "new scan" and "load scan". In the "new scan" scene I instantiate a 3d cube and make all the other points relative to it. This is my reference point. Then I instantiate some more points and finally save all the data to the device (my phone).
Next, in "load scan" I load the scene again and instantiate the cube in the exact same world position. For now, I managed to set the right position for each point but the axis is rotated because I start the scene from a different real-world location and different phone rotation.
Based on the cubes which are instantiated in the same place, I need to match the rotation and the position of the scene so the points will appear in the same relative position as the first cube.
Note: one can assume that the cube will instantiate with the user standing in the same direction as the desired position. But Do NOT assume that the user starts the "load scan" scene in the same direction as the "new scan" scene (which effect the whole scene rotation).
Here is a visualization of the problem:
Image of New Scan:
Image of Load Scan:
Thanks
If you want to make sure that the cube will appear in the same position/rotation in every AR session you have several options:
Use an Image marker
Use ARWorldMap (iOS exclusive)
Use a Cloud Tracking solution (google cloud anchors / Azure spatial anchors)
Of course you can also try to make the user place the cube correctly themselves, or redesign your app to work without these restrictions.
So I've found a solution but this is not the ultimate solution:
First, make a class with public static parameter so we can pass it through other scripts and scenes. Something like that:
public static class SceneStage
{
public static int ResetScene = 0;
}
Now, every time the camera turns on, check the SceneStage.ResetScene state. If value == 0 don't do anything, otherwise ask the user to stand facing the desire direction and then press a button, which call the function ResetScene:
private void ResetScene(int _scene)
{
var xrManagerSettings = UnityEngine.XR.Management.XRGeneralSettings.Instance.Manager;
xrManagerSettings.DeinitializeLoader();
SceneManager.LoadScene(_scene); // reload current scene
xrManagerSettings.InitializeLoaderSync();
}
Here I send the scene build index to the function with:
ResetScene(SceneManager.GetActiveScene().buildIndex);
So basically, the flow is like that: for the first time we open the scene (when SceneStage.ResetScene = 1) -> change the value to 0, and reset the scene. The second time don't do anything, but when we leave the scene set the value back to 1 so the next scene will reset too (because the ARPose driver still tracking the environment).
I am working on a basic racing game using Apple's SceneKit and am running into issues simulating a car. Using the SCNPhysicsVehicle behavior, I am able to properly set up the car and drive it using the documented methods.
However, I am unable to get the car's position. It seems logical that the SCNPhysicsVehicle would move the SCNNodes that contain the chassis and the wheels as the car moves but the SCNNodes remain at their original position and orientation. Strangely enough, the chassis' SCNPhysicsBody's velocity remains accurate throughout the simulation so I can assume that the car's position is based off of the SCNPhysicsBody and not the SCNNode. Unfortunately, there is no documented method that I have found to get an SCNPhysicsBody's position.
Getting a car's position should be trivial and is essential to create a racing game but I can't seem to find any way of getting it. Any thoughts or suggestions would be appreciated.
Scene Kit automatically updates the position of the node that owns an SCNPhysicsBody based on the physics simulation, so SCNNode.position is the right property to look for.
The catch is that there are actually two versions of that node in play. The one you typically access is called the "model" node. It reflects the target values for properties you set, even if you set those properties through an animation. The presentationNode reflects the state of the node currently being rendered — if an animation is in progress, the node's properties have intermediate values, not the target values of the animation.
Actions, physics, constraints, and any scene graph changes you make inside update/render loop methods directly target the "presentation" version of your scene graph. So, to read node properties that have been set by the physics simulation, get the presentationNode for the node you're interested in (the node that owns the vehicle's chassisBody physics body), then read the presentation node's position (or other properties).
I have the same problem with my player node.
I move it with applyForce (to manage collision detection).
But when i check node position after some movement, the node position has not move (presentation node is the actual position as rickster write in his answer)
I manage to update the scnNode.position with renderer loop
You have to set position of your node with the presentationNode position.
node.position = node.presentationNode.position
Set this into renderer(_: updateAtTime) and your node position will sync with any animation you made to the physicsBody
I have a 3d building model in my Unity project. It has many children like doors, walls etc. The problem is, all of the children points to same position in the Unity world (24.97, -2.08, 19.35). Their transforms show this position. And this position is far away from their actual one. How can i fix this?
I tried freeing all children from parent but this didn't change anything.
I want them to show their real position, which appears with move tool when we click upon them.
Here is the image link
It seems that this is simply their pivot point exported "wrongly" from the 3D editor your model was made with.
This won't change until you export it correctly from a 3D editor (Blender, Maya, etc).
Unity is not made for 3D mesh modeling and therefore in Unity itself you can't change the pivot points.
There is a very simple fix
Add a new empty GameObject
In the Inspector go to the Transform component, click on the context menu and hit Reset (you also simply set it to position 0,0,0 rotation 0,0,0 and scale 1,1,1) assuming the pivot should be at 0,0,0
Now drag and drop all objects into the empty GameObject
=> You have now one parent object with correct pivot.
By wrapping it in a parent object the childrens pivots don't matter anymore. You can simply do all translation, rotation and scaling on the parent object with the correct pivot and don't have to care about that "wrong" position at all.
I'm saw some wierd responses from Unity when I tried to do these actions :
1- I've created a Plane, simply rotated it (-32,-19,-56) and scaled it (3.21,1,2.43)
2- I've created a child cube for that plane and rotated it (-30,39,-78) and scaled it (3.54,4.8,6.42)
This is the final result in editor :
Did I do something wrong???
Why collider and renderer performing differently??
Is this a Unity bug? I'm currently using Unity 2017.3.1p1
Yes, it is some kind of bug.
To avoid it, don't child the objects directly to a non-uniformly scaled parent. Instead, child this non-uniform object (the cube) to an empty object, which will be the parent of the plane too.
Since an empty object is scaled 1,1,1, childing other objects to it don't cause this problem.
I have recently done few 3d objects in blender and I want to import them int unity3d. I know the basics: that I should export it to FBX file. But I wonder if there are any other things that are very important while exporting to unity? For example where should i position center of my object(near the ground or in the center)?
Typically you want the origin to be the bottom of the character (feet), and another good idea when importing is to make the model a child of an empty object before saving it as a prefab. That parent empty object will then have driver scripts that control stuff like movement and animation.
EDIT: This is one example of why you might want to do the empty parent method, but it isn't directly applicable to your question: http://docs.unity3d.com/Manual/HOWTO-FixZAxisIsUp.html
1) apply location, rotation and scale.
2) set the origin of the model to the bottom.
3) Delete camera and lights