I have a Cube in Unity. I'm moving and rotating the cube and I want to track the rotation around a special axis.
The Application is a Holo Lens 2 Application and I'm grabbing an Object with my hand. I then want to rotate the Object in my Hand around one of its local axis. I need that rotation around that axis, meaning a float, to rotate another object around its oft local axis by the same amount.
Any Idea how to achive this?
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I'm new to 3D design, so this might be a silly question.
I have trouble simulating wheel camber using rotation with Quaternion.
What I understand is that the rotation of the WheelCollider occurs along the X axis, whereas in my case the "visual wheel" is rotated 80 ° along the Z axis so the rotation occurs along the Y axis.
This code works well with the FL wheel because its axis is aligned with the collider axis, while it doesn't work with the FR wheel.
collider.GetWorldPose(out Vector3 position, out Quaternion rotation);
visual.transform.position = position;
// initialVisualRotation is the wuaternion rotation of the visual at Startup
// in this case: X=0 Y=0 Z=80
visual.transform.rotation = initialVisualRotation * rotation;
These are my local and global rotation axes for the right front wheel (FR).
How can I "adjust" the wheel rotation without change initial axes (as I did for the FL wheel)?
Are there some quaternion operations to adopt in these cases?
A bit of workaround for not having to deal with messed up transforms is to make object a child of another empty object.This way you can make parent object rotated to make wheel tilted but Child( actual wheel) will have its original axis always not messed with and so you can use simple script to always rotate it around same axis that is always going to be the same despite whole system(hierarchy of objects) being " tilted".
Parent is responsible on rotating around one axis and child around another.
I think you need to take a step back and arrange your prefabs this way as it seesm you did not.
Swift beginner struggling with moving a scene node in ARkit in response to the device motion.
What I want to achieve is: First detect the floor plane, then place a sphere on the floor. From that point onwards depending on the movement of the device, I want to move the sphere along its x and z axis to move it around the floor of the room. (The sphere once created needs to be in the center of the device screen and locked to that view)
So far I can detect the floor and place a node no problem. I can use device motion to obtain the device attitude (pitch, roll and yaw) but how to translate these values into meaningful x, y, z positions that I can update my node with?
Are there any formulas or methods that are used to calculate such information or is this the wrong approach? I would appreciate a link to some info or an explanation of how to go about this. Also I am unsure how to ensure the node would be always at the center of the device screen.
so, as far as I understood you want to have a following workflow:
Step 1. You create a sphere on a plane (which is already done)
Step 2. Move the sphere with respect to the camera's horizontal plane (i.e. along its x and z axis to move it around the floor of the room depending on the movement of the device)
Assuming that the Step 1 is done, what you can do:
Get the position of the camera and the sphere
This should be first called within the function that is invoked after sphere creation (be it a tapGestureRecognizer(), touchesBegan(), etc.).
You can do it by calling position property of SCNNode for sphere and for camera position and/or orientation by calling sceneView.session.currentFrame's .camera.transform which contains all necessary parameters about current position of the camera
Move the sphere as camera moves
Having the sphere position on the Scene and the transformation matrix of the camera, you can find the distance relation between them. Here you can find a good explanation of how exactly you can do it
After you get those things you should implement a proper logic within renderer(_:didUpdate:for:) to obtain continuous lock of the ball with respect to the camera position
If you are interested about the math behind it, you can kick off by reading more about transformation matrices which is a big part of Image Processing and many other areas
Hope that this will help!
I created 2 cylinders and put one on top of the other. Then I clicked to simulate physics and on each cylinder I added the following image blueprint, added a 50-point rotation on the z axis of each cylinder in opposite directions.
It turns out that in the simulation, when I perform, the cylinders rotate in one direction and move on the ground in the other direction. If it turns clockwise it moves left, and vice versa, and should be the other way around.
Can anyone help me solve this? It's for both cylinders to work together and I see how their simulation is accelerating with a constant rotation, but that's not what happens
If you want to simulate physics you should be applying forces to the cylinders using Add Torque in Radians or Add Torque in Degrees rather than modifying the rotation directly.
Alternatively, if you want to precisely control the cylinders, do not simulate physics. Instead, disable Simulate Physics and animate the rotation and position of the cylinders directly as you are.
I have a finger object. It is just three cubes representing the finger parts.
The 2nd cube is the child of the 1st one. And the 3rd cube is the child of the 2nd one.
This is the heirarchy: Cube1 -> Cube2 -> Cube3
My goal is to apply a rotation angle to the first cube and let the other cubes do the same locally.
Example: Apply 30 degrees Z rotation to the first cube, 30 degrees Z rotation to the 2nd cube, and also the 3rd one.
This will make a finger that look like this:
(Forgive me if it doesn't look like a finger)
In every Update() frame, I will change the angle (it's just one number) and it will rotate every cube for me.
My question is:
How do I make all these cubes collide properly with other objects?
I tried putting the Rigidbody on all of them and set isKinematic=false because I want to transform them myself. But I still cannot use transform.rotation to update my rotation because it will miss the collision with a ball very easily (especially the tip of the finger because it moves faster than other parts). Continuous detection doesn't help.
So I tried using rigidbody.MoveRotation() and rigidbody.MovePosition() instead, which is a pain because they need absolute values. They worked but the animation is so jumpy when I change the angle quickly.
I'm guessing that the animation is jumpy because there are many Rigidbodies or because the physics engine cannot interpolate the position of each box properly when I use MoveRotation() and MovePosition().
I need to use MovePosition() also because when I use only child.MoveRotation(transform.parent.rotation * originalChildLocalRotation * Quaternion.Euler(0, 0, angle)), the position doesn't move relative to the parent. So I have to compute child.MovePosition(parent.TransformPoint(originalLocalPositionOfTheChild)) every frame too.
I need to animate an object along a path. I am doing so by creating an animation like:.
This works great but since my terrain is not flat it will be nice if I don't have to deal with the y component. In other words I want to move an object along the x-axis and z-axis and if there is a small slope increase then increase the object y position. same thing if there is a downward slope. Or maybe I have to create a script where it checks to see if the object is colliding with the terrain. if not then decrease its y position. I don't know if this will work meanwhile animating an object though.
I think the easiest way I can think of to solve this is for you to make the object a rigid body and use collision (probably a mesh or capsule collider if its a player character) to get it to sit on the floor.