Develop Reference

Rotating field of view with player

So I have trying to create a system that looks for a ledge to climb. I have a vertical field of view that looks for these ledges and I have, so far, got it to rotate with the analogue stick's direction, so I can find a ledge and move to it where my analogue is pointing. (Look up, find ledge, move up, etc). My problem is, while the the field of view moves where I need it to move, it stays fixed on one axis and does not rotate with the player.
In the picture the cone is facing where it should be, and rotates around the player as I want it to, but as you can see, the cone faces the X-Axis and does not move from there. I want it to rotate with the player.
In the below code, the returned Vector's y value makes the cone point upwards. I have tried all manner of functions in the x and z values, but nothing is sticking.
public Vector3 DirFromAngle(float angleInDegrees, bool angleIsGlobal)
{
if(!angleIsGlobal)
{
angleInDegrees += (viewDir + 90);
}
Vector3 newValue = new Vector3(0, Mathf.Sin(angleInDegrees * Mathf.Deg2Rad), Mathf.Cos(angleInDegrees * Mathf.Deg2Rad));
return newValue;
}
The viewDir value makes the cone rotate with my analogue stick, to make the cone rotate with my player, I assume that something needs to be done with either the x or z values, or both, but for the life of me, I can't figure it out.
Thank you for any help on this issue. Apologies if my explanation isn't very good.
void OnSceneGUI()
{
LedgePointSearch lps = (LedgePointSearch)target;
Handles.color = Color.white;
Handles.DrawWireArc(lps.transform.position, lps.transform.forward * 90, Vector3.up, 360, lps.viewRadius);
Vector3 viewAngleA = lps.DirFromAngle(-lps.viewAngle / 2, false);
Vector3 viewAngleB = lps.DirFromAngle(lps.viewAngle / 2, false);
Handles.DrawLine(lps.transform.position, lps.transform.position + viewAngleA * lps.viewRadius);
Handles.DrawLine(lps.transform.position, lps.transform.position + viewAngleB * lps.viewRadius);
}
This is the editor script that displays the field of view.
The circle simply represents the radius of the field of view, how far it goes out.
https://www.dropbox.com/s/k9siha2aog9vj8o/fov.mp4?dl=0
In the video, the circle rotates with the player, and the cone rotates with my left analogue movements. I want the cone to be like the circle, with it rotating as my player does, but still matching my analogue movements.

One way to approach this is to find the Y rotation of the player and apply it to newValue before returning it.
public Vector3 DirFromAngle(float angleInDegrees, bool angleIsGlobal)
{
if(!angleIsGlobal)
{
angleInDegrees += (viewDir + 90);
}
Vector3 newValue = new Vector3(0, Mathf.Sin(angleInDegrees * Mathf.Deg2Rad), Mathf.Cos(angleInDegrees * Mathf.Deg2Rad));
// get Y rotation of player
yRotationAngle = player.transform.rotation.eulerAngles.y;
// convert to Quaternion using only the Y rotation
Quaternion yRotation = Quaternion.Euler(0f, yRotationAngle + 90f, 0f);
// Apply yRotation
newValue = yRotation * newValue;
return newValue;
}

Object Not Looking at Other Object at Right Angle in Unity3D

I'm working on a prototype of a tower defense game and I've encountered a problem with the rotation of a turret. I made it so that every turret must have a rotator part which rotates horizontally and holds the main turret body with the cannon which rotates vertically. I came up with a simple script to this but it only seems to work for the rotator and not for the cannon, at least not the way it should.
Here is the code from the script:
void Update () {
if (target != null) {
Vector3 tempRotatorRotation = rotator.transform.localEulerAngles;
rotator.transform.LookAt (target.transform);
rotator.transform.localEulerAngles = new Vector3 (tempRotatorRotation.x, rotator.transform.localEulerAngles.y, tempRotatorRotation.z);
Vector3 tempCannonRotation = cannon.transform.localEulerAngles;
cannon.transform.LookAt (target.transform);
cannon.transform.localEulerAngles = new Vector3 (cannon.transform.localEulerAngles.x, tempCannonRotation.y, tempCannonRotation.z);
}
}
And here is an image of how this turns out. The rotator is rotated perfectly, but as you can see the cannon is looking down for some reason.
(Blue is the pedestal which doesn't move. Green is rotator. Red is turret body. Light blue is cannon)
The origin of the cannon 3D model is set almost at the start of it.
Here is the screenshot of the canon selected showing it's axis and transform data

forward to unity is the blue line, which in your diagram is facing up. try this
crate empty, attach to turret so it rotates, make sure blue line(z axis) is facing your forward direction, you can do this manualy by rotating. then place your barrel as a child of that object, and point that object at target.
ive had to do this several times with blender models, since blender uses the z axis as its vertical axis not its depth axis like unity.
-turret_test
-turret_test_pedestal
-turret_test_rotater
-turret_test_turret
-AIM(new empty, orient the proper direction then add child)
-turret_test_cannon

Your cannon's barrel points in its forward direction, so all you need to use is cannon.transform.LookAt (target.transform, cannon.transform.up);
void Update () {
if (target != null) {
/* rotator code here */
// Remember which way the top of the cannon faces.
Vector3 cannonUpDirection = cannon.transform.up;
// point the cannon directly at the target
cannon.transform.LookAt (target.transform, cannonUpDirection);
}
}
If the rotator isn't pointing at/above/below the target, then you have to figure out how much to rotate the canon upwards/downwards from the horizontal, then point it in the same direction as the rotator and then do that:
void Update () {
if (target != null) {
/* rotator code here */
// Remember which way the top of the cannon faces.
Vector3 cannonUpDirection = cannon.transform.up;
// point the cannon directly at the target
cannon.transform.LookAt (target.transform, cannonUpDirection);
// Find global direction for looking straight ahead above/below the target
Vector3 sameYDirection = Vector3.Scale(
cannon.transform.forward,
new Vector3(1f,0f,1f)
);
// Convert that to local
Vector3 sameYDirectionLocal = cannon.transform
.InverseTransformDirection(sameYDirection);
// get rotation for moving from looking ahead to looking direct
Quaternion lookTowards = Quaternion.FromToRotation(
sameYDirectionLocal,
Vector3.forward
);
// lookTowards is a locally-vertical rotation from horizontal to the target,
// given some top side of the cannon.
// Clamp lookTowards here if you have a max rotation speed.
// Face cannon in same direction of rotator;
cannon.transform.rotation = Quaternion.LookRotation(
rotator.forward, cannonUpDirection);
// Use lookTowards to look down from that position.
cannon.transform.rotation *= lookTowards;
}
}

Turns out Unity is broken and when I re-imported the model all the axis have changed and instead of the canon turning in the X axis up and down now it was in the Y axis while everything else rotates horizontally in Y.
Also in the calculation I had to add + 90 to both equations. This will make no sense now since it shows both are changing in Y axis but one is rotating horizontally and the other vertically.
if (target != null) {
Vector3 tempRotatorRotation = rotator.transform.localEulerAngles;
rotator.transform.LookAt (target.transform);
rotator.transform.localEulerAngles = new Vector3 (tempRotatorRotation.x, rotator.transform.localEulerAngles.y + 90, tempRotatorRotation.z);
Vector3 tempCanonRotation = canon.transform.localEulerAngles;
canon.transform.LookAt (target.transform);
canon.transform.localEulerAngles = new Vector3 (tempCanonRotation.x, canon.transform.localEulerAngles.y + 90, tempCanonRotation.z);
}

Gyroscope with compass help needed

I need to have a game object point north AND I want to combine this with gyro.attitude input. I have tried, unsuccessfully, to do this in one step. That is, I couldn't make any gyro script, which I found on the net, work with the additional requirement of always pointing north. Trust me, I have tried every script I could find on the subject. I deduced that it's impossible and probably was stupid to think it could be done; at least not this way (i.e. all-in-one). I guess you could say I surmised that you can't do two things at once. Then I thought possibly I could get the same effect by breaking-up the duties. That is, a game object that always points north via the Y axis. Great, got that done like this:
_parentDummyRotationObject.transform.rotation = Quaternion.Slerp(_parentDummyRotationObject.transform.rotation, Quaternion.Euler(0, 360 - Input.compass.trueHeading, 0), Time.deltaTime * 5f);
And with the game object pointing north on the Y, I wanted to add the second game-object, a camera in this case, with rotation using gyro input on the X and Z axis. The reason I have to eliminate the Y axes on the camera is because I get double rotation. With two things rotating at once (i.e. camera and game-object), a 180 degree rotation yielded 360 in the scene. Remember I need the game object to always point north (IRL) based on the device compass. If my device is pointing towards the East, then my game-object would be rotated 90 degrees in the unity scene as it points (rotation) towards the north.
I have read a lot about gyro camera controllers and one thing I see mentioned a lot is you shouldn't try to do this (limit it) on just 1 or 2 axis, when using Quaternions it's impossible when you don't know what you're doing, which I clearly do not.
I have tried all 3 solutions from this solved question: Unity - Gyroscope - Rotation Around One Axis Only and each has failed to rotate my camera on 1 axis to satisfy my rotational needs. Figured I'd try getting 1 axis working before muddying the waters with the 2nd axis. BTW, my requirements are simply that the camera should only rotate on 1 axis (in any orientation) based on the X axis of my device. If I could solve for X, then I thought it'd be great to get Z gyro input to control the camera as well. So far I cannot get the camera controlled on just 1 axis (X). Anyway, here are my findings...
The first solution, which used Input.gyro.rotationRateUnbiased, was totally inaccurate. That is, if I rotated my device around a few times and then put my phone/device down on my desk, the camera would be in a different rotation/location each time. There was no consistency. Here's my code for the first attempt/solution:
<code>
private void Update()
{
Vector3 previousEulerAngles = transform.eulerAngles;
Vector3 gyroInput = Input.gyro.rotationRateUnbiased;
Vector3 targetEulerAngles = previousEulerAngles + gyroInput * Time.deltaTime * Mathf.Rad2Deg;
targetEulerAngles.y = 0.0f;
targetEulerAngles.z = 0.0f;
transform.eulerAngles = targetEulerAngles;
}
</code>
The second solution was very consistent in that I could rotate my device around and then put it down on the desk and the unity camera always ended up in the same location/rotation/state so-to-speak. The problem I had was the camera would rotate on the one axis (X in this case), but it did so when I rotated my device on either the y or x axis. Either type of rotation/movement of my phone caused the unity camera to move on the X. I don't understand why the y rotation of my phone caused the camera to rotate on X. Here is my code for solution #2:
private void Start()
{
Input.gyro.enabled = true;
startEulerAngles = transform.eulerAngles;
startGyroAttitudeToEuler = Input.gyro.attitude.eulerAngles;
}
private void Update()
{
Vector3 deltaEulerAngles = Input.gyro.attitude.eulerAngles - startGyroAttitudeToEuler;
deltaEulerAngles.y = 0.0f;
deltaEulerAngles.z = 0.0f;
transform.eulerAngles = startEulerAngles - deltaEulerAngles;
}
The 3rd solution: I wasn't sure how to complete this last solution, so it never really worked. With the 2 axis zeroed-out, the camera just flipped from facing left to right and back, or top to bottom and back; depending on which axis were commented out. If none of the axis were commented-out (like the original solution) the camera would gyro around on all axis. Here's my code for attempt #3:
private void Start()
{
_upVec = Vector3.zero;
Input.gyro.enabled = true;
startEulerAngles = transform.eulerAngles;
}
private void Update()
{
Vector3 gyroEuler = Input.gyro.attitude.eulerAngles;
phoneDummy.transform.eulerAngles = new Vector3(-1.0f * gyroEuler.x, -1.0f * gyroEuler.y, gyroEuler.z);
_upVec = phoneDummy.transform.InverseTransformDirection(-1f * Vector3.forward);
_upVec.z = 0;
// _upVec.x = 0;
_upVec.y = 0;
transform.LookAt(_upVec);
// transform.eulerAngles = _upVec;
}
Originally I thought it was my skills, but after spending a month on this I'm beginning to think that this is impossible to do. But that just can't be. I know it's a lot to absorb, but it's such a simple concept.
Any ideas?
EDIT: Thought I'd add my hierarchy:
CameraRotator (parent with script) -> MainCamera (child)
CompassRotator (parent) -> Compass (child with script which rotates parent)

I'd do this in the following way:
Camara with default 0, 0, 0 rotation
Screenshot
Object placed at the center of the default position of the camera.
Script for the Camera:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class NewBehaviourScript : MonoBehaviour
{
Camera m_MainCamera;
// Start is called before the first frame update
void Start()
{
// Disable the sleep timeout during gameplay.
// You can re-enable the timeout when menu screens are displayed as necessary.
Screen.sleepTimeout = SleepTimeout.NeverSleep;
// Enable the gyroscope.
if (SystemInfo.supportsGyroscope)
{
Input.gyro.enabled = true;
}
m_MainCamera = Camera.main;
m_MainCamera.enabled = true;
}
// Update is called once per frame
void Update()
{
if (m_MainCamera.enabled)
{
// First - Grab the Gyro's orientation.
Quaternion tAttitude = Input.gyro.attitude;
// The Device uses a 'left-hand' orientation, we need to transform it to 'right-hand'
Quaternion tGyro = new Quaternion(tAttitude.x, tAttitude.y, -tAttitude.z, -tAttitude.w);
// the gyro attitude is tilted towards the floor and upside-down reletive to what we want in unity.
// First Rotate the orientation up 90deg on the X Axis, then 180Deg on the Z to flip it right-side up.
Quaternion tRotation = Quaternion.Euler(-90f, 0, 0) * tGyro;
tRotation = Quaternion.Euler(0, 0, 180f) * tRotation;
// You can now apply this rotation to any unity camera!
m_MainCamera.transform.localRotation = tRotation;
}
}
}
With this script my Object always face SOUTH no matter what.
If you want the object to face NORTH you just have to turn the view 180º on the Y axis as a last rotation:
Quaternion tRotation = Quaternion.Euler(-90f, 0, 0) * tGyro;
tRotation = Quaternion.Euler(0, 0, 180f) * tRotation;
//Face NORTH:
tRotation = Quaternion.Euler(0,180f, 0) * tRotation;
Hope this might help ;)

TransformDirection not behaving as expected when creating RTS camera

I'm trying to create a RTS game from scratch using Unity engine. I started with this Unity RTS game tutorial and I'm setting up the camera. Basically what I do is, that I generate [x,0,z] vector for movement. I then need to apply it on camera.
It works perfectly if the camera isn't rotated - but it usually IS rotated and must be rotatable.
According to the tutorial and the docs, I can transform vector to camera's point of view using Camera.main.transform.TransformDirection(MyVector). Which is what I do:
//Get mouse position
float xpos = Input.mousePosition.x;
float ypos = Input.mousePosition.y;
//Create vector for movement
Vector3 movement = new Vector3(0, 0, 0);
//horizontal camera movement
if (xpos >= 0 && xpos < ResourceManager.ScrollWidth)
{
movement.x -= ResourceManager.ScrollSpeed;
}
else if (xpos <= Screen.width && xpos > Screen.width - ResourceManager.ScrollWidth)
{
movement.x += ResourceManager.ScrollSpeed;
}
//vertical camera movement
if (ypos >= 0 && ypos < ResourceManager.ScrollWidth)
{
movement.z -= ResourceManager.ScrollSpeed;
}
else if (ypos <= Screen.height && ypos > (Screen.height - ResourceManager.ScrollWidth))
{
movement.z += ResourceManager.ScrollSpeed;
}
//make sure movement is in the direction the camera is pointing
//but ignore the vertical tilt of the camera to get sensible scrolling
movement = Camera.main.transform.TransformDirection(movement);
//Up/down movement will be calculated diferently
movement.y = 0;
However, if I do this, the vertical movement doesn't work for the inital camera rotation, and when I rotate camera, the movement happens at strange speeds.
How can I properly apply the movement vector on camera?

Well, the problem here is that TransformDirection will preserve the lenth of the vector. So if you tilt the camera downwards the overall length get distributed between the y, x and z axis. Since you simply eliminate the y part the vector will get shorter. The more the camera is tilted the more you will lose on the other two axes.
It's usually easier to just rotate a unit vector, modify it as you want and normalize it when done. This unit vector can then be scaled by your actual movement vector. Something like that:
// [...]
Vector3 forward = Camera.main.transform.forward;
Vector3 right = Camera.main.transform.right;
forward.y = 0f;
right.y = 0f; // not needed unless your camera is also rotated around z
movement = forward.normalized * movement.z + right.normalized * movement.x;
// [...]
Another approach is to seperate your two rotations. So by using an empty GameObject that is only rotated around y and have the camera a child of that gameobject. Now the camera will only be rotated around the local x axis to tilt it the way you want. To lat the camera look into a different direction you rotate the empty GameObject around y. That way you can use the transform of the empty GameObject to transform the direction just the way you did in your code since the tilt of the camera doesn't matter.

FPS style camera target calculation in XNA

What I need is to calculate where my lookat 3d vector would be based upon the camera position, the Y rotation and Z rotation, I would assume that any number greater than 0 would be sufficient for the distance from the camera to look at.
Here is the static class I'm using to control the camera and calculate the view and projection matrices, etc.
Class members that involve the position and rotation:
public static Vector3 Position { get; set; } //Publicly available for use outside the class
public static Vector3 Rotation { get; set; }
private static Vector3 camPos = new Vector3(0.0f, 200.0f, 300.0f); //However we work with these for manipulation of values
private static Vector3 camTarget = new Vector3(0, 0, -1200.0f);
private static float rotY = 0, rotZ = 0; //I believe that these are the correct axis following the right hand catasian coordinate system
My camera's update function:
public static void Update()
{
//Controls here
//Update Position here
Position = camPos;
//Update camTarget based on Position, rotY and rotZ <- Need help with this bit
//After calculating camTarget update Rotation
Rotation = camTarget;
UpdateMatrices();
}
UpdateMatrices() handles everything else and works as it should but here it is just in case you would like to see it:
public static void UpdateMatrices()
{
Matrix rotationMatrix = Matrix.CreateRotationX(MathHelper.ToRadians(90));
Vector3 transformedReference = Vector3.Transform(Vector3.Forward, rotationMatrix);
View = Matrix.CreateLookAt(Position, Rotation, Vector3.Forward);
Projection = Matrix.CreatePerspectiveFieldOfView(MathHelper.PiOver4, aspectRatio, nearClip, farClip);
World = Matrix.Identity;
CamBoundingFrustrum = new BoundingFrustum(View * Projection);
}
Would anyone be kind enough to share the secret to this please?

Rather than using Vector3.Forward, pull the .Forward and .Up vectors from your rotation matrix:
public void UpdateMatrices()
{
/// assumes Rotation is a Vector3 containing rotation around each axis expressed in radians
Matrix rotationMatrix = Matrix.CreateFromYawPitchRoll(Rotation.Y, Rotation.X, Rotation.Z);
/// View = Matrix.CreateLookAt(Position, Rotation, Vector3.Forward);
View = Matrix.CreateLookAt(Position, Position + rotationMatrix.Forward, rotationMatrix.Up);
Projection = Matrix.CreatePerspectiveFieldOfView(MathHelper.PiOver4, aspectRatio, nearClip, farClip);
/// World matrix needs to match your translation and rotation used above
/// XNA expects matrices to be concatenated in SRT (scale, rotation, then translate) order:
World = rotationMatrix * Matrix.CreateTranslation(Position);
CamBoundingFrustrum = new BoundingFrustum(View * Projection);
}
Note that you have to add the camera's translation (via a vector you're storing, or from the camera's world matrix .Translation property) to the RotationMatrix.Forward to get a real target.
The matrix .Forward, .Backward,.Left,.Right,.Up and .Down properties are the same as the equivalent Vector3 properties transformed by the rotation matrix. so, RotationMatrix.Forward points in the direction you're looking, .Up is orthogonal to that, etc.
If you just use Vector3.Forward, you don't get a transformed vector, and weird things can happen.
Other notes:
Don't make everything static. Create an instance of your camera class during Game.Initialize() and add it as a property. static should be used with caution - it can cause all sorts of fun threading issues that will drive you insane.
I'd also recommend switching to a quaternion instead of yaw/roll/pitch (if you haven't already) since it avoids gimble lock, but that's a different topic.