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Unable to rotate cube in desired manner - plane and mousemove method

The cube should stay flat but rotate towards the cursor, with only one type of rotation (2d - top-down). My concern now is that it may be due to centring the mesh against itself? Please help!
View here:
https://thecoop.group/conquest/ground
The code begins here:
https://github.com/the-coop/coopwebsite/blob/89ca8909ed3fe28afd79b34c5305b63aabba8638/lib/conquest/ground/engine/setupGroundMovement.js#L35
Here is the excerpt, I have tried many different ways and some of the experimental code may remain:
const plane = new Plane(new Vector3(0, 1, 0), 1);
const raycaster = new Raycaster();
const mouse = new Vector2();
const pointOfIntersection = new Vector3();
document.addEventListener('mousemove', ev => {
const { camera, me } = window.GROUND_LEVEL;
mouse.x = ( ev.clientX / window.innerWidth ) * 2 - 1;
mouse.y = - ( ev.clientY / window.innerHeight ) * 2 + 1;
raycaster.setFromCamera(mouse, camera);
raycaster.ray.intersectPlane(plane, pointOfIntersection);
if (me.mesh) {
// Attempt to make mesh "look at" (rotate) to target position.
me.mesh.geometry.lookAt(pointOfIntersection);
}
});

pointOfIntersection has 3 dimensions that correspond to the cube's three axes.
If you only want the cube to rotate on one axis, try specifying 0 for the other axes in Object3D#lookAt.
// The cube will rotate on its Y axis when following a point on the X axis
me.mesh.geometry.lookAt(pointOfIntersection.x, 0, 0);

Mapping a stereographic projection to the inside of a sphere in ThreeJS

When it comes to 3D animation, there are a lot of terms and concepts that I'm not familiar with (maybe a secondary question to append to this one: what are some good books to get familiar with the concepts?). I don't know what a "UV" is (in the context of 3D rendering) and I'm not familiar with what tools exist for mapping pixels on an image to points on a mesh.
I have the following image being produced by a 360-degree camera (it's actually the output of an HTML video element):
I want the center of this image to be the "top" of the sphere, and any radius of the circle in this image to be an arc along the sphere from top to bottom.
Here's my starting point (copying lines of code directly from the Three.JS documentation):
var video = document.getElementById( "texture-video" );
var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera( 75, window.innerWidth / window.innerHeight, 0.1, 1000 );
var renderer = new THREE.WebGLRenderer();
renderer.setSize( window.innerWidth, window.innerHeight );
document.body.appendChild( renderer.domElement );
var texture = new THREE.VideoTexture( video );
texture.minFilter = THREE.LinearFilter;
texture.magFilter = THREE.LinearFilter;
texture.format = THREE.RGBFormat;
var material = new THREE.MeshBasicMaterial( { map: texture } );
var geometry = new THREE.SphereGeometry(0.5, 100, 100);
var mesh = new THREE.Mesh( geometry, material );
scene.add( mesh );
camera.position.z = 1
function animate()
{
mesh.rotation.y += 0.01;
requestAnimationFrame( animate );
renderer.render( scene, camera );
}
animate();
This produces the following:
There are a few problems:
The texture is rotated 90 degrees
The ground is distorted, although this may be fixed if the rotation is fixed?
Update: Upon further investigation of the sphere being produced, it's not actually rotated 90 degrees. Instead, the top of the image is the top of the sphere and the bottom of the image is the bottom of the sphere. This causes the left and right edges of the image to become the distorted "sideways ground" I saw
This is on the outside of the sphere. I want to project this to the inside of the sphere (and place the camera inside the sphere)
Currently if I place the camera inside the sphere I get solid black. I don't think it's a lighting issue because the Three.JS docs said that a MeshBasicMaterial didn't need lighting. I think the issue may be that the normals of all of the sphere faces point outward and I need to reverse them. I'm not sure how one would do this - but I'm pretty sure it's possible since I think this is how skyboxes work.
Doing some research I'm pretty sure I need to modify the "UV"s to fix this, I just don't know how or really what that even means...

Working Example
I forked #manthrax's CodeSandbox.io solution and updated it with my own:
https://codesandbox.io/s/4w1njkrv9
The Solution
So after spending a day researching UV mapping to understand what it meant and how it worked, I was able to sit down and scratch out some trig to map points on a sphere to points on my stereographic image. It basically came down to the following:
Use arccosine of the Y coordinate to determine the magnitude of a polar coordinate on the stereographic image
Use the arctangent of the X and Z coordinates to determine the angle of the polar coordinate on the stereographic image
Use x = Rcos(theta), y = Rsin(theta) to compute the rectangular coordinates on the stereographic image
If time permits I may draw a quick image in Illustrator or something to explain the math, but it's standard trigonometry
I went a step further after this, because the camera I was using only has a 240 degree vertical viewing angle - which caused the image to get slightly distorted (especially near the ground). By subtracting the vertical viewing angle from 360 and dividing by two, you get an angle from the vertical within which no mapping should occur. Because the sphere is oriented along the Y axis, this angle maps to a particular Y coordinate - above which there's data, and below which there isn't.
Calculate this "minimum Y value"
For all points on the sphere:
If the point is above the minimum Y value, scale it linearly so that the first such value is counted as "0" and the top of the sphere is still counted as "1" for mapping purposes
If the point is below the minimum Y value, return nothing
Weird Caveats
For some reason the code I wrote flipped the image upside down. I don't know if I messed up on my trigonometry or if I messed up on my understanding of UV maps. Whatever the case, this was trivially fixed by flipping the sphere 180 degrees after mapping
As well, I don't know how to "return nothing" in the UV map, so instead I mapped all points below the minimum Y value to the corner of the image (which was black)
With a 240-degree viewing angle the space at the bottom of the sphere with no image data was sufficiently large (on my monitor) that I could see the black circle when looking directly ahead. I didn't like the visual appearance of this, so I plugged in 270 for the vertical FOV. this leads to minor distortion around the ground, but not as bad as when using 360.
The Code
Here's the code I wrote for updating the UV maps:
// Enter the vertical FOV for the camera here
var vFov = 270; // = 240;
var material = new THREE.MeshBasicMaterial( { map: texture, side: THREE.BackSide } );
var geometry = new THREE.SphereGeometry(0.5, 200, 200);
function updateUVs()
{
var maxY = Math.cos(Math.PI * (360 - vFov) / 180 / 2);
var faceVertexUvs = geometry.faceVertexUvs[0];
// The sphere consists of many FACES
for ( var i = 0; i < faceVertexUvs.length; i++ )
{
// For each face...
var uvs = faceVertexUvs[i];
var face = geometry.faces[i];
// A face is a triangle (three vertices)
for ( var j = 0; j < 3; j ++ )
{
// For each vertex...
// x, y, and z refer to the point on the sphere in 3d space where this vertex resides
var x = face.vertexNormals[j].x;
var y = face.vertexNormals[j].y;
var z = face.vertexNormals[j].z;
// Because our stereograph goes from 0 to 1 but our vertical field of view cuts off our Y early
var scaledY = (((y + 1) / (maxY + 1)) * 2) - 1;
// uvs[j].x, uvs[j].y refer to a point on the 2d texture
if (y < maxY)
{
var radius = Math.acos(1 - ((scaledY / 2) + 0.5)) / Math.PI;
var angle = Math.atan2(x, z);
uvs[j].x = (radius * Math.cos(angle)) + 0.5;
uvs[j].y = (radius * Math.sin(angle)) + 0.5;
} else {
uvs[j].x = 0;
uvs[j].y = 0;
}
}
}
// For whatever reason my UV mapping turned everything upside down
// Rather than fix my math, I just replaced "minY" with "maxY" and
// rotated the sphere 180 degrees
geometry.rotateZ(Math.PI);
geometry.uvsNeedUpdate = true;
}
updateUVs();
var mesh = new THREE.Mesh( geometry, material );
The Results
Now if you add this mesh to a scene everything looks perfect:
One Thing I Still Don't Understand
Right around the "hole" at the bottom of the sphere there's a multi-colored ring. It almost looks like a mirror of the sky. I don't know why this exists or how it got there. Could anyone shed light on this in the comments?

Here is as close as I could get it in about 10 minutes of fiddling with a polar unwrapping of the uv's.
You can modify the polarUnwrap function to try and get a better mapping....
https://codesandbox.io/s/8nx75lkn28
You can replace the TextureLoader().loadTexture() with
//assuming you have created a HTML video element with id="video"
var video = document.getElementById( 'video' );
var texture = new THREE.VideoTexture( video );
texture.minFilter = THREE.LinearFilter;
texture.magFilter = THREE.LinearFilter;
texture.format = THREE.RGBFormat;
to get your video fed in there...
More info here:
https://threejs.org/docs/#api/textures/VideoTexture
Also this may be useful to you:
https://community.theta360.guide/t/displaying-thetas-dual-fisheye-video-with-three-js/1160

I think, it's would be quite difficult to modify the UVs, so that the stereographic projected image will fit. The UVs of a sphere are set to fit textures with equirectangular projection.
To transform the image from stereographic to equirectangular, you might want to use Panorama tools like PTGui or Hugin. Or you can use Photoshop (apply Filter > Distort > Polar Coordinates > polar to rectangular).
Equirectangular projection of the image (with Photoshop), resized to 2:1 aspect ratio (not necessary for texture)
If you want the texture to be inside the sphere (or normals flipped), you are able to set the material to THREE.BackSide.
var material = new THREE.MeshBasicMaterial( { map: texture, side: THREE.BackSide } );
Maybe, you have to flip the texture horizontally then: How to flip a Three.js texture horizontally

Click to place camera near an object in Three js

My I am trying to do a click to zoom feature with Three.js, I have a canvas and an object loaded in the canvas.On click I am trying to place the camera near the point of intersection(Actually like zooming that point).
Here is what I have done, but doesn't work as I wanted, on click camera positions changes but kind of works partially sometimes camera is placed near the point of intersection, some times not.
onmousedown = function (event) {
var raycaster = new THREE.Raycaster();
var mouse = new THREE.Vector2();
event.preventDefault();
mouse.x = (event.clientX / self.renderer.domElement.clientWidth) * 2 - 1;
mouse.y = -(event.clientY / self.renderer.domElement.clientHeight) * 2 + 1;
raycaster.setFromCamera(mouse, self.camera);
var objects = [];
for (var i = 0; i < self.scene.children.length; i++) {
if (self.scene.children[i] instanceof THREE.Group) {
objects.push(self.scene.children[i]);
}
}
console.log(objects);
var intersects = raycaster.intersectObjects( objects,true );
console.log(intersects.length);
if (intersects.length > 0) {
self.camera.up = new THREE.Vector3(0, 0, 1);
self.camera.lookAt(new THREE.Vector3(0, 0, 0));
self.camera.position.z = intersects[0].point.z * .9;
self.camera.position.x = intersects[0].point.x * .9;
self.camera.position.y = intersects[0].point.y * .9;
}
};
Here self is a global viewer object which holds camera, canvas, different objects etc.
0.9 is just a number used to place camera just near the point of intersection.
camera used is PerspectiveCamera and controls is TrackballControls
new THREE.PerspectiveCamera(90, this.width / this.height, 1, 1000);
The objects loaded are from .obj or .dae files ,I expect this to work like click on any point on the object and place the camera near that point. But camera is moving but sometimes not near the point I clicked.
Does intersects[0] gives the nearest intersection point? or nearest in the direction of camera ?
What is my mistake here ?
I am new to three js , just started learning it.If something or some logic is wrong help me with that.

The position is a bit complicated to calculate; you have to find the segment between camera and intersection and than place the camera at specific distance from intersection along the segment looking to the intersection point.
try this:
var length=[the desiderated distance camera-intersection]
var dir = camera.position.clone().sub(intersects[0].point).normalize().multiplyScalar(length);
camera.position = intersects[0].point.clone().add(dir);
camera.lookAt(intersects[0].point);

I have created a fiddle: http://jsfiddle.net/h5my29aL/
It's not so difficult. Think of your object as a planet, and your camera as a satellite. You need to position the camera somewhere in an orbit near your object. Three contains a distanceTo function that makes it simple. The example uses a sphere, but it will work with an arbitrary mesh. It measures the distance from the center point to the desired vector3. In your case the vector3 is likely the face position returned by a picker ray. But anyhow, the lookAt is set to the mesh, and then a distance from the vertex is calculated so that the camera is always the same altitude regardless of a vertex's or face's distance from the object center.
var point = THREE.GeometryUtils.randomPointsInGeometry( geometry, 1 );
var altitude = 100;
var rad = mesh.position.distanceTo( point[0] );
var coeff = 1+ altitude/rad;
camera.position.x = point[0].x * coeff;
camera.position.y = point[0].y * coeff;
camera.position.z = point[0].z * coeff;
camera.lookAt(mesh.position);

I've came somewhat close to what I want with an example from Three js.
Three JS webgl_decals
this is what I have done.
function zoomCam(event) {
var point_mouse = new THREE.Vector2(),
var point_x = null;
var point_y = null;
if (event.changedTouches) {
point_x = event.changedTouches[ 0 ].pageX;
point_y = event.changedTouches[ 0 ].pageY;
} else {
point_x = event.clientX;
point_y = event.clientY;
}
point_mouse.x = (point_x / window.innerWidth) * 2 - 1;
point_mouse.y = -(point_y / window.innerHeight) * 2 + 1;
if (sceneObjects.length > 0) {
var raycaster = new THREE.Raycaster();
raycaster.setFromCamera(point_mouse, camera);
var intersects = raycaster.intersectObjects(sceneObjects, true);
if (intersects.length > 0) {
var p = intersects[ 0 ].point;
var n = intersects[ 0 ].face.normal.clone();
n.multiplyScalar(10);
n.add(intersects[ 0 ].point);
camera.position.copy(n);
camera.lookAt(p);
}
}
There might be some minor issues as I formatted/changed the code for answering here. Check the code before implementing.

Three.js 2D X, Y coords to 3D X, Y, Z coords always in front of camera

I've looked at this question:
Mouse / Canvas X, Y to Three.js World X, Y, Z
and have implemented it in my code, the problem is that I can't seem to get it to work as others have stated.
I need to place an object in front of the camera via X and Y screen coords, not necessarily from the mouse.
This object will be at a specified distance in front of the camera, either from a pre-defined maximum distance or a calculated object distance.
Note: My Camera can be at any position in my scene and facing any direction
Here is my code:
this.reticlePos.x = 500;
this.reticlePos.y = 300;
this.reticlePos.z = 0.5;
this.projector.unprojectVector(this.reticlePos, this.camera);
//check for collisions, if collisions set distance to collision distance
var distance = this.RETICLE_RADIUS;
var direction = new THREE.Vector3( 0, 0, -1 );
direction.applyQuaternion( this.camera.quaternion );
this.rayCaster.set(this.camera.position, direction);
var collisionResults = this.rayCaster.intersectObjects(this.sceneController.obstacles);
if( collisionResults.length !== 0 ) {
// console.log('Ray collides with mesh. Distance :' + collisionResults[0].distance);
distance = collisionResults[0].distance - 20;
}
// set the reticle position
var dir = this.reticlePos.clone().sub( this.camera.position ).normalize();
var pos = this.camera.position.clone().add( dir.multiplyScalar( distance ) );
this.reticleMesh.position.copy( pos );
As you can see is is very similar to the linked question, yet I cannot see the object in front of my camera.
Any insight into this would be greatly appreciated.

I figured out the answer myself for anyone that checks this question later on.
To get my screen coordinates I needed to convert some input data from a gyroscope, and didn't realize that I still needed to do the following to my calculated screen coordinates:
this.reticlePos.x = ( this.reticlePos.x / window.innerWidth ) * 2 - 1;
this.reticlePos.y = - ( this.reticlePos.y / window.innerHeight ) * 2 + 1;
After doing this, everything works as expected.

THREE.js: Need Help rotating with Quaternions

I'm looking to understand quaternions for three.js, but for all the tutorials, I haven't been able to translate them into the application I need. This is the problem:
Given a sphere centered at (0,0,0), I want to angle an object on the sphere's surface, that acts as the focal point for the camera. This point is to be moved and rotated on the surface with keyboard input.
Setting the focal point into a chosen orbit is easy of course, but maintaining the right rotation perpendicular to the surface escapes me. I know quaternions are neccessary for smooth movement and arbitrary axis rotation, but I don't know where to start.
The second part then is rotating the camera offset with the focal point. The snippet I found for this does not have the desired effect anymore, as the cameraOffset does not inherit the rotation:
var cameraOffset = relativeCameraOffset.clone().applyMatrix4( focalPoint.matrixWorld );
camera.position.copy( focalPoint.position.clone().add(cameraOffset) );
camera.lookAt( focalPoint.position );
Update 1: Tried it with fixed camera on the pole and rotating the planet. But unless I'm missing something important, this fails as well, due to the directions getting skewed completely when going towards the equator. (Left becomes forward). Code in update is:
acceleration.set(0,0,0);
if (keyboard.pressed("w")) acceleration.x = 1 * accelerationSpeed;
if (keyboard.pressed("s")) acceleration.x = -1 * accelerationSpeed;
if (keyboard.pressed("a")) acceleration.z = 1 * accelerationSpeed;
if (keyboard.pressed("d")) acceleration.z = -1 * accelerationSpeed;
if (keyboard.pressed("q")) acceleration.y = 1 * accelerationSpeed;
if (keyboard.pressed("e")) acceleration.y = -1 * accelerationSpeed;
velocity.add(acceleration);
velocity.multiplyScalar(dropOff);
velocity.max(minV);
velocity.min(maxV);
planet.mesh.rotation.x += velocity.x;
planet.mesh.rotation.y += velocity.y;
planet.mesh.rotation.z += velocity.z;
So I'm still open for suggestions.

Finally found the solution from a mixture of matrices and quaternions:
//Setup
var ux = new THREE.Vector3(1,0,0);
var uy = new THREE.Vector3(0,1,0);
var uz = new THREE.Vector3(0,0,1);
var direction = ux.clone();
var m4 = new THREE.Matrix4();
var dq = new THREE.Quaternion(); //direction quad base
var dqq; //final direction quad
var dq2 = new THREE.Quaternion();
dq2.setFromAxisAngle(uz,Math.PI/2); //direction perpendicular rot
//Update
if (velocity.length() < 0.1) return;
if (velocity.x) { focalPoint.translateY( velocity.x ); }
if (velocity.y) { focalPoint.translateX( velocity.y ); }
//create new direction from focalPoint quat, but perpendicular
dqq = dq.clone().multiply(focalPoint.quaternion).multiply(dq2);
velocity.multiplyScalar(dropOff);
//forward direction vector
direction = ux.clone().applyQuaternion(dqq).normalize();
//use Matrix4.lookAt to align focalPoint with the direction
m4.lookAt(focalPoint.position, planet.mesh.position, direction);
focalPoint.quaternion.setFromRotationMatrix(m4);
var cameraOffset = relativeCameraOffset.clone();
cameraOffset.z = cameraDistance;
cameraOffset.applyQuaternion(focalPoint.quaternion);
camera.position = focalPoint.position.clone().add(cameraOffset) ;
//use direction for camera rotation as well
camera.up = direction;
camera.lookAt( focalPoint.position );
This is the hard core of it. It pans (and with some extension rotates) around the planet without the poles being an issue.

I'm not sure to understand your problem.
But for help, I draw a boat on a sphere with the code below.
var geometry = new THREE.ShapeGeometry(shape);
var translation = new THREE.Matrix4().makeTranslation(boat.position.x, boat.position.y, boat.position.z);
var rotationZ = new THREE.Matrix4().makeRotationZ(-THREE.Math.degToRad(boat.cap));
var rotationX = new THREE.Matrix4().makeRotationX(-THREE.Math.degToRad(boat.latitude));
var rotationY = new THREE.Matrix4().makeRotationY(Math.PI / 2 + THREE.Math.degToRad(boat.longitude));
var roationXY = rotationY.multiply(rotationX);
geometry.applyMatrix(rotationZ);
geometry.applyMatrix(roationXY );
geometry.applyMatrix(translation);
First, I apply a rotation on Z to define boat cap
Then, I apply
rotation on Y,X to to set the boat perpendicular to the surface of
the sphere
Finally I apply a translation to put the boat on the
surafce of the sphere
The rotations order is important