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Why the translation is laggy in ThreeJS?

I am new to ThreeJS and still exploring the library.
I have a very basic example of drawing a white dot, with a simple translation force.
let dotGeometry = new THREE.Geometry();
let dotMaterial = new THREE.PointsMaterial({
size: 10,
color: 0xffffff,
});
dotGeometry.vertices.push(new THREE.Vector3(1, 0, -1));
let dot = new THREE.Points(dotGeometry, dotMaterial);
scene.add(dot);
function animate() {
requestAnimationFrame(animate);
dot.position.x += 0.01;
renderer.render(scene, camera);
}
animate();
I was wondering why the translation is pretty laggy even with a single point rendered on screen.
Is there a better way to achieve smoother transformations, am I doing something wrong?
Many thanks in advance.
Andrea

Actually you should always honor the time delta of a single animation step when transforming objects. In this way, a value like 0.1 gets a better semantic. It's 0.1 world units per second. It also makes the animation more smooth and independent of the framerate. Try this code:
const camera = new THREE.PerspectiveCamera(70, window.innerWidth / window.innerHeight, 0.01, 10);
camera.position.z = 5;
const scene = new THREE.Scene();
const clock = new THREE.Clock();
const dotGeometry = new THREE.Geometry();
const dotMaterial = new THREE.PointsMaterial({
size: 10,
color: 0xffffff,
});
dotGeometry.vertices.push(new THREE.Vector3(1, 0, -1));
const dot = new THREE.Points(dotGeometry, dotMaterial);
scene.add(dot);
const renderer = new THREE.WebGLRenderer({
antialias: true
});
renderer.setPixelRatio( window.devicePixelRatio );
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);
function animate() {
requestAnimationFrame(animate);
const delta = clock.getDelta();
dot.position.x += 0.1 * delta;
renderer.render(scene, camera);
}
animate();
body {
margin: 0;
}
<script src="https://cdn.jsdelivr.net/npm/three#0.123/build/three.js"></script>

Creating a cylinder with slanted bottom

I want to create a cylinder with slanted bottom shape in three.js.
I don't see any direct way to create such geometry in three.js. I tried to see if I can cut the cylinder by a slanted plane, but could not find such operation in the documentation. Can anybody suggest a way to create this?

You can operate with vertices as you want.
Just a simple concept:
var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 1, 1000);
camera.position.set(0, 0, 10);
var renderer = new THREE.WebGLRenderer({
antialias: true
});
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);
var controls = new THREE.OrbitControls(camera, renderer.domElement);
var light = new THREE.DirectionalLight(0xffffff, 0.5);
light.position.setScalar(10);
scene.add(light);
scene.add(new THREE.AmbientLight(0xffffff, 0.5));
var cylGeom = new THREE.CylinderBufferGeometry(1, 1, 5, 16);
var vertices = cylGeom.attributes.position;
// change upper vertices
var v3 = new THREE.Vector3(); // temp vector
for (let i = 0; i < vertices.count; i++) {
v3.fromBufferAttribute(vertices, i); // set the temp vector
v3.y = v3.y > 0 ? (v3.x * 0.5) + 2.5 : v3.y; // change position by condition and equation
vertices.setY(i, v3.y); // set Y-component of a vertex
}
var cylMat = new THREE.MeshLambertMaterial({
color: "aqua"
});
var cyl = new THREE.Mesh(cylGeom, cylMat);
scene.add(cyl);
renderer.setAnimationLoop(() => {
renderer.render(scene, camera)
});
body {
overflow: hidden;
margin: 0;
}
<script src="https://threejs.org/build/three.min.js"></script>
<script src="https://threejs.org/examples/js/controls/OrbitControls.js"></script>

Set 3d cube rotation origin

I have a simple 3d cube (BoxGeometry of 100, 100, 100) and I am trying to rotate it. If we call all 100x100x100 a tile - when I rotate it I can see it's overlapping the below tile.
(by changing color, now I totally understand the behaviour).
tl.to(this.cube4.rotation, 0.5, {z: -45* Math.PI/180});
[
What if I want to rotate it based on an anchor point of right bottom? So instead of overflowing inside the below tile, it will overflow that portion to above tile.
So it will look like the green example and not the red example:
The red example here is achieved by
tl.to(this.cube4.rotation, 0.5, {z: -45* Math.PI/180});
tl.to(this.cube4.position, 0.5, {x: 50 }, 0.5);
I am very new to three.js so if any terminology is wrong, please warn me

Add the ("red") cube to a THREE.Group, in that way that the rotation axis (the edge) is in the origin of the group. This means the cube has to be shifted by the half side length.
If you rotate the group object, then the cube (which is inside the group) will rotate around the edge and not around its center.
e.g.
var bbox = new THREE.Box3().setFromObject(cube);
cube.position.set(bbox.min.x, bbox.max.y, 0);
var pivot = new THREE.Group();
pivot.add(cube);
scene.add(pivot);
See also the answer to How to center a group of objects?, which uses this solution to rotate a group of objects.
(function onLoad() {
var camera, scene, renderer, orbitControls, pivot;
var rot = 0.02;
init();
animate();
function init() {
container = document.getElementById('container');
renderer = new THREE.WebGLRenderer({
antialias: true,
alpha: true
});
renderer.setPixelRatio(window.devicePixelRatio);
renderer.setSize(window.innerWidth, window.innerHeight);
renderer.shadowMap.enabled = true;
container.appendChild(renderer.domElement);
camera = new THREE.PerspectiveCamera(70, window.innerWidth / window.innerHeight, 1, 100);
camera.position.set(4, 1, 2);
//camera.lookAt( -1, 0, 0 );
loader = new THREE.TextureLoader();
loader.setCrossOrigin("");
scene = new THREE.Scene();
scene.background = new THREE.Color(0xffffff);
scene.add(camera);
window.onresize = function() {
renderer.setSize(window.innerWidth, window.innerHeight);
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
}
orbitControls = new THREE.OrbitControls(camera, container);
var ambientLight = new THREE.AmbientLight(0x404040);
scene.add(ambientLight);
var directionalLight = new THREE.DirectionalLight( 0xffffff, 0.5 );
directionalLight.position.set(1,2,-1.5);
scene.add( directionalLight );
addGridHelper();
createModel();
}
function createModel() {
var material = new THREE.MeshPhongMaterial({color:'#80f080'});
var geometry = new THREE.BoxGeometry( 1, 1, 1 );
var cube1 = new THREE.Mesh(geometry, material);
cube1.position.set(0,-0.5,-0.5);
var cube2 = new THREE.Mesh(geometry, material);
cube2.position.set(0,0.5,-0.5);
var cube3 = new THREE.Mesh(geometry, material);
cube3.position.set(0,-0.5,0.5);
var material2 = new THREE.MeshPhongMaterial({color:'#f08080'});
var cube4 = new THREE.Mesh(geometry, material2);
var bbox = new THREE.Box3().setFromObject(cube4);
cube4.position.set(bbox.min.x, bbox.max.y, 0);
pivot = new THREE.Group();
pivot.add(cube4);
pivot.position.set(-bbox.min.x, 0.5-bbox.max.y, 0.5);
scene.add(cube1);
scene.add(cube2);
scene.add(cube3);
scene.add(pivot);
}
function addGridHelper() {
var helper = new THREE.GridHelper(100, 100);
helper.material.opacity = 0.25;
helper.material.transparent = true;
scene.add(helper);
var axis = new THREE.AxesHelper(1000);
scene.add(axis);
}
function animate() {
requestAnimationFrame(animate);
orbitControls.update();
pivot.rotation.z += rot;
if (pivot.rotation.z > 0.0 || pivot.rotation.z < -Math.PI/2) rot *= -1;
render();
}
function render() {
renderer.render(scene, camera);
}
})();
<!--script src="https://threejs.org/build/three.js"></!--script-->
<script src="https://rawcdn.githack.com/mrdoob/three.js/r124/build/three.js"></script>
<script src="https://rawcdn.githack.com/mrdoob/three.js/r124/examples/js/controls/OrbitControls.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/tween.js/17.2.0/Tween.js"></script>
<div id="container"></div>

From the first image, it appears that the pivot of your red tile is at its center.
For the rotation you want, you would ideally change the pivot to the lower right of the cube. This is impossible without modifying the geometry of the cube.
BUT a simple trick is to create an empty node at that pivot point, parent your cube to that empty, and apply your rotation to the empty. (Don't forget to remove your translation, you don't need it anymore)
Here is some pseudo code, assuming your red box is centered at (0,0,0) and has a width and height of 100:
// create an empty node at desired rotation pivot
var empty = new Object3D or group
empty.position = (50, -50, 0)
// parent your cube to the empty
var cube = your box
empty.add(cube)
// you may need to change the local position of your cube to bring it back to its global position of (0,0,0)
cube.position = (-50, 50, 0)
rotate empty by 45°

I think you can get the bounds of the rotated object like this:
bounds = new THREE.Box3().setFromObject( theRedObject )
Then reposition the object.y based on its bounds.min.y
let scene, camera, controls, ambient, point, loader, renderer, container, stats;
const targetRotation = 0;
const targetRotationOnMouseDown = 0;
const mouseX = 0;
const mouseXOnMouseDown = 0;
const windowHalfX = window.innerWidth / 2;
const windowHalfY = window.innerHeight / 2;
init();
animate();
var box, b1, b2, b3;
function init() {
// Create a scene which will hold all our meshes to be rendered
scene = new THREE.Scene();
// Create and position a camera
camera = new THREE.PerspectiveCamera(
60, // Field of view
window.innerWidth / window.innerHeight, // Aspect ratio
/*window.innerWidth / -8,
window.innerWidth / 8,
window.innerHeight / 8,
window.innerHeight / -8,
*/
0.1, // Near clipping pane
1000 // Far clipping pane
);
scene.add(camera)
// Reposition the camera
camera.position.set(0, 5, 10);
// Point the camera at a given coordinate
camera.lookAt(new THREE.Vector3(0, 0, 0));
// Add orbit control
controls = new THREE.OrbitControls(camera);
controls.target.set(0, -0.5, 0);
controls.update();
// Add an ambient lights
ambient = new THREE.AmbientLight(0xffffff, 0.2);
scene.add(ambient);
// Add a point light that will cast shadows
point = new THREE.PointLight(0xffffff, 1);
point.position.set(25, 50, 25);
point.castShadow = true;
point.shadow.mapSize.width = 1024;
point.shadow.mapSize.height = 1024;
scene.add(point);
group = new THREE.Group();
group.position.y = 0;
scene.add(group);
rotationAnchor = new THREE.Object3D()
group.add(rotationAnchor);
box = new THREE.Mesh(new THREE.BoxGeometry(), new THREE.MeshStandardMaterial({
color: 'grey'
}))
b1 = box.clone();
b2 = box.clone();
b3 = box.clone();
b3.material = b3.material.clone()
b3.material.color.set('red')
group.add(box);
group.add(b1);
b1.position.y += 1
group.add(b2);
b2.position.z += 1
rotationAnchor.add(b3);
rotationAnchor.position.set(0.5, 0.5, 1.5)
b3.position.set(-.5, -.5, -.5)
// Create a renderer
renderer = new THREE.WebGLRenderer({
antialias: true
});
// Set size
renderer.setPixelRatio(window.devicePixelRatio);
renderer.setSize(window.innerWidth, window.innerHeight);
// Set color
renderer.setClearColor(0xf8a5c2);
renderer.gammaOutput = true;
// Enable shadow mapping
renderer.shadowMap.enabled = true;
renderer.shadowMap.type = THREE.PCFSoftShadowMap;
// Append to the document
container = document.createElement("div");
document.body.appendChild(container);
document.body.appendChild(renderer.domElement);
// Add resize listener
window.addEventListener("resize", onWindowResize, false);
// Enable FPS stats
stats = new Stats();
container.appendChild(stats.dom);
var gui = new dat.GUI({
height: 5 * 32 - 1
});
let params = {
'test': 4,
'bevelThickness': 1,
'bevelSize': 1.5,
'bevelSegments': 3
}
gui.add(params, 'test', 0, 10).onChange(val => {
test = val
})
}
function onWindowResize() {
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize(window.innerWidth, window.innerHeight);
}
function animate() {
rotationAnchor.rotation.z = (Math.cos(performance.now() * 0.001) * Math.PI * 0.25) + (Math.PI * 1.25)
requestAnimationFrame(animate);
// Re-render scene
renderer.render(scene, camera);
// Update stats
stats.update();
}
body {
overflow: hidden;
margin: 0;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/96/three.min.js"></script>
<script src="https://threejs.org/examples/js/controls/OrbitControls.js"></script>
<script src="https://threejs.org/examples/js/libs/stats.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/dat-gui/0.7.2/dat.gui.min.js"></script>

Three.js: Project Objects onto Plane Perpendicular to Camera

I have a simple scene in Three with some planes. Right now on click the planes move to random positions.
After a click, I'd like instead to move the planes into a new grid perpendicular to the camera, such that the projected grid's x and y axes are parallel with the screen's x and y axes.
Here's the scene:
// generate a scene object
var scene = new THREE.Scene();
scene.background = new THREE.Color(0xffffff);
// generate a camera
var aspectRatio = window.innerWidth / window.innerHeight;
var camera = new THREE.PerspectiveCamera(75, aspectRatio, 0.01, 10000);
// position the camera
camera.position.set(51.389, -451.056, 839.455);
var rotObjectMatrix = new THREE.Matrix4();
var q = {_x: 0.0184, _y: -0.2122, _z: 0.9770, _w: -0.0081};
rotObjectMatrix.makeRotationFromQuaternion(q);
camera.quaternion.setFromRotationMatrix(rotObjectMatrix);
camera.up.set(0.00806, -0.91008, -0.41432);
// generate a renderer
var renderer = new THREE.WebGLRenderer({antialias: true});
renderer.setPixelRatio(window.devicePixelRatio); // <3 retina
renderer.setSize(window.innerWidth, window.innerHeight); // canvas size
document.body.appendChild(renderer.domElement);
// generate controls
var controls = new THREE.TrackballControls(camera, renderer.domElement);
controls.target.set(19.053, -111.316, 93.996);
// generate some lights
var ambientLight = new THREE.AmbientLight(0xeeeeee);
scene.add(ambientLight);
// render loop
function render() {
requestAnimationFrame(render);
renderer.render(scene, camera);
controls.update();
};
// draw a grid
var grid = new THREE.GridHelper(2000, 20, 0x000000, 0x000000);
grid.material.opacity = 0.2;
grid.material.transparent = true;
grid.rotation.x = -Math.PI;
scene.add(grid);
// draw some
planes = [];
for (var i=0; i<2**10; i++) {
var geometry = new THREE.PlaneGeometry( 20, 20, 32 );
var material = new THREE.MeshBasicMaterial(
{color: 0xff0000, side: THREE.DoubleSide} );
var plane = new THREE.Mesh( geometry, material );
var x = ((i % 2**5) * 40) - (2**5 * 40)/2;
var z = (Math.floor(i/2**5) * 40) - (2**5 * 40)/2;
plane.position.set(x, 0, z);
scene.add(plane);
planes.push(plane);
}
// transition the planes on body click
document.querySelector('body').addEventListener('click', function() {
planes.forEach(function(plane) {
// placeholder
plane.position.set(
Math.random() * 500 - (Math.random() * 500)/2,
0,
Math.random() * 500 - (Math.random() * 500)/2,
)
})
})
render();
html, body { width: 100%; height: 100%; background: #000; }
body { margin: 0; overflow: hidden; }
canvas { width: 100%; height: 100%; }
<script src='https://cdnjs.cloudflare.com/ajax/libs/three.js/97/three.min.js'></script>
<script src='https://threejs.org/examples/js/controls/TrackballControls.js'></script>
Using the following comes close, but doesn't tilt the planes such that they're perpendicular to the camera:
planes.forEach(function(plane) {
// close to projection discussed above...
plane.position.set(
plane.position.x,
plane.position.z,
0,
)
})
Does anyone know how to achieve the projection described above? Any suggestions others can offer would be greatly appreciated!

This is a bit of a shortcut, but it'll help you avoid a lot of math calculations: Just group your planes into a Group and then use Group.lookAt(camera.position) to point them all in unison towards the camera.
// generate a scene object
var scene = new THREE.Scene();
scene.background = new THREE.Color(0xffffff);
// generate a camera
var aspectRatio = window.innerWidth / window.innerHeight;
var camera = new THREE.PerspectiveCamera(75, aspectRatio, 0.01, 10000);
// position the camera
camera.position.set(51.389, -451.056, 839.455);
var rotObjectMatrix = new THREE.Matrix4();
var q = {_x: 0.0184, _y: -0.2122, _z: 0.9770, _w: -0.0081};
rotObjectMatrix.makeRotationFromQuaternion(q);
camera.quaternion.setFromRotationMatrix(rotObjectMatrix);
// Not sure why you're changing camera's up axis, but this will
// need to be duplicated on planeGroup;
camera.up.set(0.00806, -0.91008, -0.41432);
// generate a renderer
var renderer = new THREE.WebGLRenderer({antialias: true});
renderer.setPixelRatio(window.devicePixelRatio); // <3 retina
renderer.setSize(window.innerWidth, window.innerHeight); // canvas size
document.body.appendChild(renderer.domElement);
// generate controls
var controls = new THREE.TrackballControls(camera, renderer.domElement);
// If you change the pos where the camera is looking at,
// you'll need to place planeGroup at this position.
controls.target.set(19.053, -111.316, 93.996);
// generate some lights
var ambientLight = new THREE.AmbientLight(0xeeeeee);
scene.add(ambientLight);
// render loop
function render() {
requestAnimationFrame(render);
renderer.render(scene, camera);
controls.update();
};
// draw a grid
var grid = new THREE.GridHelper(2000, 20, 0x000000, 0x000000);
grid.material.opacity = 0.2;
grid.material.transparent = true;
grid.rotation.x = -Math.PI;
scene.add(grid);
// draw some
planes = [];
var planeGroup = new THREE.Group();
for (var i=0; i<2**10; i++) {
var geometry = new THREE.PlaneGeometry( 20, 20, 32 );
var material = new THREE.MeshBasicMaterial(
{color: 0xff0000, side: THREE.DoubleSide} );
var plane = new THREE.Mesh( geometry, material );
var x = ((i % 2**5) * 40) - (2**5 * 40)/2;
var y = (Math.floor(i/2**5) * 40) - (2**5 * 40)/2;
// Setting x,y instead of x,z
plane.position.set(x, y, 0);
planeGroup.add(plane);
planes.push(plane);
}
scene.add(planeGroup);
// Copying camera.up and controls.target from above
planeGroup.up.copy(camera.up);
planeGroup.position.copy(controls.target);
planeGroup.lookAt(camera.position);
// transition the planes on body click
document.querySelector('body').addEventListener('click', function() {
planes.forEach(function(plane) {
// placeholder
plane.position.set(
Math.random() * 500 - (Math.random() * 500)/2,
0,
Math.random() * 500 - (Math.random() * 500)/2,
)
})
})
render();
html, body { width: 100%; height: 100%; background: #000; }
body { margin: 0; overflow: hidden; }
canvas { width: 100%; height: 100%; }
<script src='https://cdnjs.cloudflare.com/ajax/libs/three.js/97/three.min.js'></script>
<script src='https://threejs.org/examples/js/controls/TrackballControls.js'></script>
Then, if you want to randomize the plane's positions, you can still do that, but all you have to worry about afterward is to return them to their original x,y,0 positions, and they'll automatically line up "looking at" the camera.
EDIT: I had to copy the changes you made to camera.up and controls.target for this to work. If you change these 2 attributes, you'll need to copy them to planeGroup for this approach to work.
Here's the doc on the .lookAt() method

Three.js increase box geometry from only one side

I'm new in three.js, and my first feature was to create a box geometry which can increased from only one side.
Problem : When you increase width or height of an object the two sides automatically increased.
jsFiddle Example
So i lost 1 hour, to find the good algorythm :
geometry = new THREE.BoxGeometry(strength, 200, 200);
material = new THREE.MeshBasicMaterial({
color: 0xff0000
});
mesh = new THREE.Mesh(geometry, material);
mesh.applyMatrix( new THREE.Matrix4().makeTranslation( - strength + strength / 2, 0, 0 ) );
Someone can explain me: - strength + strength / 2 (If i increase the strength by 1 the translation is only -0.5 not -1 ?)
What is the name of this sort of algorythm, where i can find good ressources to learn this purpose (beginner)?

Also, you can shift the geometry with .translate() method, thus you won't have a container object in the scene graph:
var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 1, 1000);
camera.position.set(2, 3, 5);
var renderer = new THREE.WebGLRenderer({
antialias: true
});
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);
var controls = new THREE.OrbitControls(camera, renderer.domElement);
scene.add(new THREE.GridHelper(10, 10));
var boxGeom = new THREE.BoxGeometry();
boxGeom.translate(0.5, 0.5, 0); // pivot point is shifted
var box = new THREE.Mesh(boxGeom, new THREE.MeshNormalMaterial());
scene.add(box);
var clock = new THREE.Clock();
var delta = 0;
var time = 0;
render();
function render() {
requestAnimationFrame(render);
delta = clock.getDelta();
time += delta;
box.scale.set(2.5 + Math.sin(time) * 2, 1.5, 1.5);
renderer.render(scene, camera);
}
body {
overflow: hidden;
margin: 0;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/95/three.min.js"></script>
<script src="https://threejs.org/examples/js/controls/OrbitControls.js"></script>

Another option:
var container = new THREE.Object3D()
var boxMesh = new THREE.Mesh(new THREE.BoxGeometry(1,1,1));
boxMesh.position.set(0.5,0.5,0.5)
container.add(boxMesh)
scene.add(container)
container.scale.set(strength,200,200);
https://en.wikipedia.org/wiki/Scene_graph