How to fit my big data into the screen that fits end to end? - position

const scene = new THREE.Scene();
// create a camera, which defines where we're looking at.
const camera = new THREE.PerspectiveCamera( 25, window.innerWidth /
window.innerHeight, 0.5, 1000 );
// create a render and set the size
const renderer = new THREE.WebGLRenderer();
renderer.setSize( window.innerWidth, window.innerHeight );
// add the output of the renderer to the html element
document.body.appendChild( renderer.domElement );
// create orbiting camera controls
const controls = new OrbitControls( camera, renderer.domElement );
// position the camera
camera.position.z = 100;
camera.position.y = 10;
camera.position.x = 10;
// get the data using fetch
fetch( './json/HLE.json' )
.then( response => response.json() )
.then( data => {
// callback that is called once the data has been fetched
// iterate through the data
let i = 0;
data.forEach( row => {
// do something for each row
console.log(row.Country_Code);
console.log(row.YR2019);
// create a cube with dimensions according to the row
const max = 90;
const height = row.YR2019 / max;
const geometry = new THREE.BoxGeometry( 0.5, height, 0.5 );
const material = new THREE.MeshBasicMaterial( { color: 0x336699 } );
const cube = new THREE.Mesh( geometry, material );
scene.add( cube );
// offset the cube to the right by the index i times offset width (to spread)
const offsetWidth = 1.0;
cube.position.x = i * offsetWidth;
// shift the cube upwards by half it's height
cube.position.y = height / 2;
// increment the index i
i += 1;
} );
} )
// Now we're ready to render our scene
//This function will be called every frame
function animate() {
// ask the browser to call this function again when it's ready to draw the next frame
requestAnimationFrame( animate );
// update the camera controls
controls.update();
// render the scene
renderer.render( scene, camera );
}
// call the animate function
animate();

Related

Coloring faces of a Three.js BoxGeometry

I saw some solutions that accessed the THREE.BoxGeometry faces like that:
var geometry = new THREE.BoxGeometry(n,n,n)
let faces = geometry.faces;
for (let face of faces) {
face.color.set(Math.random() * 0xffffff);
}
But it seems that the faces-array doesn't exist in the current Three.js version r129 (Uncaught TypeError: faces is not iterable).
How can I achieve an easy coloring of the six cube faces?
Try it like so:
let camera, scene, renderer, mesh;
init();
animate();
function init() {
camera = new THREE.PerspectiveCamera( 70, window.innerWidth / window.innerHeight, 0.01, 10 );
camera.position.z = 1;
scene = new THREE.Scene();
const geometry = new THREE.BoxGeometry( 0.2, 0.2, 0.2 ).toNonIndexed();
// vertexColors must be true so vertex colors can be used in the shader
const material = new THREE.MeshBasicMaterial( { vertexColors: true } );
// generate color data for each vertex
const positionAttribute = geometry.getAttribute( 'position' );
const colors = [];
const color = new THREE.Color();
for ( let i = 0; i < positionAttribute.count; i += 3 ) {
color.set( Math.random() * 0xffffff );
// define the same color for each vertex of a triangle
colors.push( color.r, color.g, color.b );
colors.push( color.r, color.g, color.b );
colors.push( color.r, color.g, color.b );
}
// define the new attribute
geometry.setAttribute( 'color', new THREE.Float32BufferAttribute( colors, 3 ) );
mesh = new THREE.Mesh( geometry, material );
scene.add( mesh );
renderer = new THREE.WebGLRenderer( { antialias: true } );
renderer.setSize( window.innerWidth, window.innerHeight );
document.body.appendChild( renderer.domElement );
}
function animate() {
requestAnimationFrame( animate );
mesh.rotation.x += 0.01;
mesh.rotation.y += 0.02;
renderer.render( scene, camera );
}
body {
margin: 0;
}
<script src="https://cdn.jsdelivr.net/npm/three#0.129.0/build/three.js"></script>
The previous geometry format was removed from the core with r125. More information in the following post at the three.js forum.
https://discourse.threejs.org/t/three-geometry-will-be-removed-from-core-with-r125/22401

Three.js Server Rendering

I am trying to create a script that loads my .obj and .mtl files in three.js and then takes a screenshot of it. I'm doing this for rendering items and characters on my website. I made a function called renderItem that calls the .php page on which the item is rendered and the screenshot is taken but the only way to get it to work is by echoing the contents of the page (not really what I wanted to do).
Now I am looking at using three.js with node to render my items on the server. I've been researching different ways people have done this for days and I can get it to work using a CanvasRenderer or headless gl, but now my issue is that only loading simple boxes works with that. My .obj files and my .mtl files load but do not show up at all. I have been working on this code for over a week and I cannot find anyone else with the same issue I am having. Idk what else to do so any help would be appreciated. I will paste the code below:
var MockBrowser = require('mock-browser').mocks.MockBrowser;
var mock = new MockBrowser();
global.document = mock.getDocument();
global.window = MockBrowser.createWindow();
global.THREE = require('three');
var Canvas = require('canvas');
var gl = require("gl")(500, 500);
var OBJLoader = require('three/examples/js/loaders/OBJLoader.js');
var MTLLoader = require('three/examples/js/loaders/MTLLoader.js');
require('three/examples/js/renderers/CanvasRenderer.js');
require('three/examples/js/renderers/Projector.js');
global.XMLHttpRequest = require('xhr2').XMLHttpRequest;
var scene, camera, renderer, controls;
var express = require('express');
var app = express();
const fitCameraToObject = function ( camera, object, offset, controls ) {
offset = offset || 1.25;
const boundingBox = new THREE.Box3();
// get bounding box of object - this will be used to setup controls and camera
boundingBox.setFromObject( object );
const center = boundingBox.getCenter();
const size = boundingBox.getSize();
// get the max side of the bounding box (fits to width OR height as needed )
const maxDim = Math.max( size.x, size.y, size.z );
const fov = camera.fov * ( Math.PI / 180 );
let cameraZ = Math.abs( maxDim / 4 * Math.tan( fov * 2 ) );
cameraZ *= offset; // zoom out a little so that objects don't fill the screen
camera.position.z = cameraZ;
const minZ = boundingBox.min.z;
const cameraToFarEdge = ( minZ < 0 ) ? -minZ + cameraZ : cameraZ - minZ;
camera.far = cameraToFarEdge * 3;
camera.updateProjectionMatrix();
if ( controls ) {
// set camera to rotate around center of loaded object
controls.target = center;
// prevent camera from zooming out far enough to create far plane cutoff
controls.maxDistance = cameraToFarEdge * 2;
controls.saveState();
} else {
camera.lookAt( center )
}
}
function init() {
var manager = new THREE.LoadingManager();
scene = new THREE.Scene();
camera = new THREE.PerspectiveCamera( 70, 1, 0.01, 100 );
camera.position.set(-0.25,0.86,0.76);
var canvas = new Canvas.createCanvas(500, 500);
canvas.style = {}; // dummy shim to prevent errors during render.setSize
var renderer = new THREE.CanvasRenderer({
canvas: canvas
});
renderer.setSize( 500, 500 );
// lighting
ambientLight = new THREE.AmbientLight(0xffffff,1.4);
scene.add(ambientLight);
var mtlLoader = new THREE.MTLLoader();
mtlLoader.setTexturePath('texturepath');
mtlLoader.setPath('mtlpath');
mtlLoader.load('Boots.mtl', function(materials) {
materials.preload();
var objLoader = new THREE.OBJLoader(manager);
objLoader.setMaterials(materials);
objLoader.setPath('objpath');
objLoader.load('Boots.obj', function(object) {
scene.add(object);
fitCameraToObject(camera, object, 7, controls);
renderer.render( scene, camera );
});
});
/*
var geometry = new THREE.BoxGeometry( 1, 1, 1 );
var material = new THREE.MeshBasicMaterial( { color: 0x00ff00 } );
var cube = new THREE.Mesh( geometry, material );
scene.add( cube );
camera.position.z = 5;*/
var animate = function () {
//requestAnimationFrame( animate );
renderer.render( scene, camera );
};
animate();
manager.onLoad = function () {
renderer.render( scene, camera );
console.log('Image: ' + renderer.domElement.toDataURL('image/png'));
};
}
app.get('/', function(req, res) {
res.send(req.params);
init();
});
app.listen(3000, function() {
console.log('Server started on Port 3000...');
});
I changed the paths because I don't want my website name to be shown but I can confirm that the object and mtl loads correctly. I commented out the code that makes a box but when it isn't commented it prints out a base64 code which I just paste into a website I found online and it shows me an image of the green box. The MTL/OBJ Loader part prints out a base64 code but doesn't show anything. If I need to give more info let me know but I am completely lost.

three.js orbit object around a changing axis

I have a simple 3D object and I am able to rotate i.e., move with my left mouse button, around the centre of axis - works fine. When I pan using the right mouse button the axis also shifts, as such it no longer moves around it’s present axis.
How can I move the object around it’s current axis, no matter where I drag the object?
Below is the complete code of script.js
var scene = new THREE.Scene();
var axisHelper = new THREE.AxisHelper(100);
scene.add(axisHelper);
var camera = new THREE.PerspectiveCamera( 75, window.innerWidth/window.innerHeight, 0.1, 1000 );
camera.position.y = -200;
var renderer = new THREE.WebGLRenderer();
renderer.setSize( window.innerWidth, window.innerHeight );
document.body.appendChild( renderer.domElement );
var controls = new THREE.OrbitControls(camera, renderer.domElement);
controls.enableDamping = true;
controls.dampingFactor = 0.25;
controls.enableZoom = true;
var keyLight = new THREE.DirectionalLight(new THREE.Color('hsl(30, 100%, 75%)'), 1.0);
keyLight.position.set(-100, 0, 100);
var fillLight = new THREE.DirectionalLight(new THREE.Color('hsl(240, 100%, 75%)'), 0.75);
fillLight.position.set(100, 0, 100);
var backLight = new THREE.DirectionalLight(0xffffff, 1.0);
backLight.position.set(100, 0, -100).normalize();
scene.add(keyLight);
scene.add(fillLight);
scene.add(backLight);
var mtlLoader = new THREE.MTLLoader();
mtlLoader.setTexturePath('assets/');
mtlLoader.setPath('assets/');
mtlLoader.load('180319_object01.mtl', function (materials) {
materials.preload();
var objLoader = new THREE.OBJLoader();
objLoader.setMaterials(materials);
objLoader.setPath('assets/');
objLoader.load('180319_object01.obj', function (object) {
object.scale.set( 200, 200, 200 );
scene.add(object);
object.position.x = -100;
object.position.y = -100;
object.position.z = 0;
});
});
var animate = function () {
requestAnimationFrame( animate );
controls.update();
renderer.render(scene, camera);
};
animate();
It is because your camera is being moved by the controller and not the object itself, rather than update the cameras position and direction ((ie which is what the orbit controller is doing).in your render method you'll want to update position and Euler angle on the object itself to achieve the desired effect. To do this you'll want to track and update the position and angle of rotation about the (y?) Axis of the object,in the object (model) space.hope that makes sense, let me know if you need me to elaborate.

Three.js scene does not render in Safari 11.0.2

I'm trying to determine why a Three.js scene does not render in Safari 11.0.2 (OSX 10.12.6).
/**
* Generate a scene object with a background color
**/
function getScene() {
var scene = new THREE.Scene();
scene.background = new THREE.Color(0x111111);
return scene;
}
/**
* Generate the camera to be used in the scene. Camera args:
* [0] field of view: identifies the portion of the scene
* visible at any time (in degrees)
* [1] aspect ratio: identifies the aspect ratio of the
* scene in width/height
* [2] near clipping plane: objects closer than the near
* clipping plane are culled from the scene
* [3] far clipping plane: objects farther than the far
* clipping plane are culled from the scene
**/
function getCamera() {
var aspectRatio = window.innerWidth / window.innerHeight;
var camera = new THREE.PerspectiveCamera(75, aspectRatio, 0.1, 10000);
camera.position.set(0,150,400);
camera.lookAt(scene.position);
return camera;
}
/**
* Generate the light to be used in the scene. Light args:
* [0]: Hexadecimal color of the light
* [1]: Numeric value of the light's strength/intensity
* [2]: The distance from the light where the intensity is 0
* #param {obj} scene: the current scene object
**/
function getLight(scene) {
var lights = [];
lights[0] = new THREE.PointLight( 0xffffff, 0.6, 0 );
lights[0].position.set( 100, 200, 100 );
scene.add( lights[0] );
var ambientLight = new THREE.AmbientLight(0x111111);
scene.add(ambientLight);
return light;
}
/**
* Generate the renderer to be used in the scene
**/
function getRenderer() {
// Create the canvas with a renderer
var renderer = new THREE.WebGLRenderer({antialias: true});
// Add support for retina displays
renderer.setPixelRatio(window.devicePixelRatio);
// Specify the size of the canvas
renderer.setSize(window.innerWidth, window.innerHeight);
// Add the canvas to the DOM
document.body.appendChild(renderer.domElement);
return renderer;
}
/**
* Generate the controls to be used in the scene
* #param {obj} camera: the three.js camera for the scene
* #param {obj} renderer: the three.js renderer for the scene
**/
function getControls(camera, renderer) {
var controls = new THREE.TrackballControls(camera, renderer.domElement);
controls.zoomSpeed = 0.4;
controls.panSpeed = 0.4;
return controls;
}
/**
* Get grass
**/
function getPlane(scene, loader) {
var texture = loader.load('grass.jpg');
texture.wrapS = texture.wrapT = THREE.RepeatWrapping;
texture.repeat.set( 10, 10 );
var material = new THREE.MeshBasicMaterial({
map: texture, side: THREE.DoubleSide
});
var geometry = new THREE.PlaneGeometry(1000, 1000, 10, 10);
var plane = new THREE.Mesh(geometry, material);
plane.position.y = -0.5;
plane.rotation.x = Math.PI / 2;
scene.add(plane);
return plane;
}
/**
* Add background
**/
function getBackground(scene, loader) {
var imagePrefix = '';
var directions = ['right', 'left', 'top', 'bottom', 'front', 'back'];
var imageSuffix = '.bmp';
var geometry = new THREE.BoxGeometry( 1000, 1000, 1000 );
var materialArray = [];
for (var i = 0; i < 6; i++)
materialArray.push( new THREE.MeshBasicMaterial({
map: loader.load(imagePrefix + directions[i] + imageSuffix),
side: THREE.BackSide
}));
var sky = new THREE.Mesh( geometry, materialArray );
scene.add(sky);
}
/**
* Add a character
**/
function getSphere(scene) {
var geometry = new THREE.SphereGeometry( 30, 12, 9 );
var material = new THREE.MeshPhongMaterial({
color: 0xd0901d,
emissive: 0xaf752a,
side: THREE.DoubleSide,
flatShading: true
});
var sphere = new THREE.Mesh( geometry, material );
// create a group for translations and rotations
var sphereGroup = new THREE.Group();
sphereGroup.add(sphere)
sphereGroup.position.set(0, 24, 100);
scene.add(sphereGroup);
return [sphere, sphereGroup];
}
/**
* Store all currently pressed keys
**/
function addListeners() {
window.addEventListener('keydown', function(e) {
pressed[e.key.toUpperCase()] = true;
})
window.addEventListener('keyup', function(e) {
pressed[e.key.toUpperCase()] = false;
})
}
/**
* Update the sphere's position
**/
function moveSphere() {
var delta = clock.getDelta(); // seconds
var moveDistance = 200 * delta; // 200 pixels per second
var rotateAngle = Math.PI / 2 * delta; // pi/2 radians (90 deg) per sec
// move forwards/backwards/left/right
if ( pressed['W'] ) {
sphere.rotateOnAxis(new THREE.Vector3(1,0,0), -rotateAngle)
sphereGroup.translateZ( -moveDistance );
}
if ( pressed['S'] )
sphereGroup.translateZ( moveDistance );
if ( pressed['Q'] )
sphereGroup.translateX( -moveDistance );
if ( pressed['E'] )
sphereGroup.translateX( moveDistance );
// rotate left/right/up/down
var rotation_matrix = new THREE.Matrix4().identity();
if ( pressed['A'] )
sphereGroup.rotateOnAxis(new THREE.Vector3(0,1,0), rotateAngle);
if ( pressed['D'] )
sphereGroup.rotateOnAxis(new THREE.Vector3(0,1,0), -rotateAngle);
if ( pressed['R'] )
sphereGroup.rotateOnAxis(new THREE.Vector3(1,0,0), rotateAngle);
if ( pressed['F'] )
sphereGroup.rotateOnAxis(new THREE.Vector3(1,0,0), -rotateAngle);
}
/**
* Follow the sphere
**/
function moveCamera() {
var relativeCameraOffset = new THREE.Vector3(0,50,200);
var cameraOffset = relativeCameraOffset.applyMatrix4(sphereGroup.matrixWorld);
camera.position.x = cameraOffset.x;
camera.position.y = cameraOffset.y;
camera.position.z = cameraOffset.z;
camera.lookAt(sphereGroup.position);
}
// Render loop
function render() {
requestAnimationFrame(render);
renderer.render(scene, camera);
moveSphere();
moveCamera();
};
// state
var pressed = {};
var clock = new THREE.Clock();
// globals
var scene = getScene();
var camera = getCamera();
var light = getLight(scene);
var renderer = getRenderer();
// add meshes
var loader = new THREE.TextureLoader();
var floor = getPlane(scene, loader);
var background = getBackground(scene, loader);
var sphereData = getSphere(scene);
var sphere = sphereData[0];
var sphereGroup = sphereData[1];
addListeners();
render();
body { margin: 0; overflow: hidden; }
canvas { width: 100%; height: 100%; }
<script src='https://cdnjs.cloudflare.com/ajax/libs/three.js/88/three.min.js'></script>
<script src='https://threejs.org/examples/js/controls/TrackballControls.js'></script>
More generally, all of the examples at shadertoy.com [example] either do not appear or appear very faintly and almost entirely in white on Safari 11.0.2.
The same holds for the "Safari Technology Preview" even after I turn on all experimental web features, including WebGL 2.0.
I'd like to figure out how to make the scene render, but I'm more interested in learning how others attempt to debug this kind of problem. Are there tools or resources that can help one pinpoint this kind of problem (like a developer tools just for WebGL)?
This looks like a compositing bug in Safari. Hopefully Apple will fix it.
There are several workrounds. The easist seems to be to set the background color of the body or canvas to black.
/**
* Generate a scene object with a background color
**/
function getScene() {
var scene = new THREE.Scene();
scene.background = new THREE.Color(0x111111);
return scene;
}
/**
* Generate the camera to be used in the scene. Camera args:
* [0] field of view: identifies the portion of the scene
* visible at any time (in degrees)
* [1] aspect ratio: identifies the aspect ratio of the
* scene in width/height
* [2] near clipping plane: objects closer than the near
* clipping plane are culled from the scene
* [3] far clipping plane: objects farther than the far
* clipping plane are culled from the scene
**/
function getCamera() {
var aspectRatio = window.innerWidth / window.innerHeight;
var camera = new THREE.PerspectiveCamera(75, aspectRatio, 0.1, 10000);
camera.position.set(0,150,400);
camera.lookAt(scene.position);
return camera;
}
/**
* Generate the light to be used in the scene. Light args:
* [0]: Hexadecimal color of the light
* [1]: Numeric value of the light's strength/intensity
* [2]: The distance from the light where the intensity is 0
* #param {obj} scene: the current scene object
**/
function getLight(scene) {
var lights = [];
lights[0] = new THREE.PointLight( 0xffffff, 0.6, 0 );
lights[0].position.set( 100, 200, 100 );
scene.add( lights[0] );
var ambientLight = new THREE.AmbientLight(0x111111);
scene.add(ambientLight);
return light;
}
/**
* Generate the renderer to be used in the scene
**/
function getRenderer() {
// Create the canvas with a renderer
var renderer = new THREE.WebGLRenderer({antialias: true});
// Add support for retina displays
renderer.setPixelRatio(window.devicePixelRatio);
// Specify the size of the canvas
renderer.setSize(window.innerWidth, window.innerHeight);
// Add the canvas to the DOM
document.body.appendChild(renderer.domElement);
return renderer;
}
/**
* Generate the controls to be used in the scene
* #param {obj} camera: the three.js camera for the scene
* #param {obj} renderer: the three.js renderer for the scene
**/
function getControls(camera, renderer) {
var controls = new THREE.TrackballControls(camera, renderer.domElement);
controls.zoomSpeed = 0.4;
controls.panSpeed = 0.4;
return controls;
}
/**
* Get grass
**/
function getPlane(scene, loader) {
var texture = loader.load('grass.jpg');
texture.wrapS = texture.wrapT = THREE.RepeatWrapping;
texture.repeat.set( 10, 10 );
var material = new THREE.MeshBasicMaterial({
map: texture, side: THREE.DoubleSide
});
var geometry = new THREE.PlaneGeometry(1000, 1000, 10, 10);
var plane = new THREE.Mesh(geometry, material);
plane.position.y = -0.5;
plane.rotation.x = Math.PI / 2;
scene.add(plane);
return plane;
}
/**
* Add background
**/
function getBackground(scene, loader) {
var imagePrefix = '';
var directions = ['right', 'left', 'top', 'bottom', 'front', 'back'];
var imageSuffix = '.bmp';
var geometry = new THREE.BoxGeometry( 1000, 1000, 1000 );
var materialArray = [];
for (var i = 0; i < 6; i++)
materialArray.push( new THREE.MeshBasicMaterial({
map: loader.load(imagePrefix + directions[i] + imageSuffix),
side: THREE.BackSide
}));
var sky = new THREE.Mesh( geometry, materialArray );
scene.add(sky);
}
/**
* Add a character
**/
function getSphere(scene) {
var geometry = new THREE.SphereGeometry( 30, 12, 9 );
var material = new THREE.MeshPhongMaterial({
color: 0xd0901d,
emissive: 0xaf752a,
side: THREE.DoubleSide,
flatShading: true
});
var sphere = new THREE.Mesh( geometry, material );
// create a group for translations and rotations
var sphereGroup = new THREE.Group();
sphereGroup.add(sphere)
sphereGroup.position.set(0, 24, 100);
scene.add(sphereGroup);
return [sphere, sphereGroup];
}
/**
* Store all currently pressed keys
**/
function addListeners() {
window.addEventListener('keydown', function(e) {
pressed[e.key.toUpperCase()] = true;
})
window.addEventListener('keyup', function(e) {
pressed[e.key.toUpperCase()] = false;
})
}
/**
* Update the sphere's position
**/
function moveSphere() {
var delta = clock.getDelta(); // seconds
var moveDistance = 200 * delta; // 200 pixels per second
var rotateAngle = Math.PI / 2 * delta; // pi/2 radians (90 deg) per sec
// move forwards/backwards/left/right
if ( pressed['W'] ) {
sphere.rotateOnAxis(new THREE.Vector3(1,0,0), -rotateAngle)
sphereGroup.translateZ( -moveDistance );
}
if ( pressed['S'] )
sphereGroup.translateZ( moveDistance );
if ( pressed['Q'] )
sphereGroup.translateX( -moveDistance );
if ( pressed['E'] )
sphereGroup.translateX( moveDistance );
// rotate left/right/up/down
var rotation_matrix = new THREE.Matrix4().identity();
if ( pressed['A'] )
sphereGroup.rotateOnAxis(new THREE.Vector3(0,1,0), rotateAngle);
if ( pressed['D'] )
sphereGroup.rotateOnAxis(new THREE.Vector3(0,1,0), -rotateAngle);
if ( pressed['R'] )
sphereGroup.rotateOnAxis(new THREE.Vector3(1,0,0), rotateAngle);
if ( pressed['F'] )
sphereGroup.rotateOnAxis(new THREE.Vector3(1,0,0), -rotateAngle);
}
/**
* Follow the sphere
**/
function moveCamera() {
var relativeCameraOffset = new THREE.Vector3(0,50,200);
var cameraOffset = relativeCameraOffset.applyMatrix4(sphereGroup.matrixWorld);
camera.position.x = cameraOffset.x;
camera.position.y = cameraOffset.y;
camera.position.z = cameraOffset.z;
camera.lookAt(sphereGroup.position);
}
// Render loop
function render() {
requestAnimationFrame(render);
renderer.render(scene, camera);
moveSphere();
moveCamera();
};
// state
var pressed = {};
var clock = new THREE.Clock();
// globals
var scene = getScene();
var camera = getCamera();
var light = getLight(scene);
var renderer = getRenderer();
// add meshes
var loader = new THREE.TextureLoader();
var floor = getPlane(scene, loader);
var background = getBackground(scene, loader);
var sphereData = getSphere(scene);
var sphere = sphereData[0];
var sphereGroup = sphereData[1];
addListeners();
render();
body { margin: 0; overflow: hidden; }
canvas { width: 100%; height: 100%; background: black; }
<script src='https://cdnjs.cloudflare.com/ajax/libs/three.js/88/three.min.js'></script>
<script src='https://threejs.org/examples/js/controls/TrackballControls.js'></script>
As for how to know how to find this bugs, in this particular case I don't know how I knew except experience. I know it's unfortunately common for browsers to get compositing bugs with WebGL because it's very hard to test. Most browsers test on servers without GPUs which means they don't test WebGL enough. They built their testing systems before compositing was GPU accelerated. Another reason is testing compositing is something that's browser specific so the WebGL tests can't include a test for it. It's something each browser vendor has to implement their own tests for and often their testing systems run the browsers in non-release modes or the APIs that might make it possible to test don't actually go through the same code as the code the draws to the screen .
For WebGL, you should generally get the same results across browsers and compositing issues are the most common place they get it wrong. Especially when not using the defauts. So, first I checked the if the context was set up non-default as in either alpha: false or premultipliedAlpha: false etc.. To do that I just opened Chrome's dev tools and selected the snippet context
Once I had the correct debugger context I just got the WebGL context from the first canvas
I saw alpha: false which is not the default so that was the first clue. If there was more than one canvas I would have had to use 'querySelectorAll' and try each canvas until I got the WebGL one.
Then I also saw your CSS is different than I would do it. I would have used
body { margin: 0; }
canvas { width: 100vw; height: 100vw; display: block; }
No need for overflow: hidden and clearly states what I want. I have strong opinions that the way most three.js apps size the canvas is an anti-pattern.
I saw that you set your css to make the canvas height 100% but you didn't set the body height and so if nothing else was done your canvas would have zero height. So, I set the background color of the canvas so I could see how big it was. I was assuming it was actually zero. That's when (a) I saw it was rendering and setting the background color made it appear and (b) your canvas appears because three.js is hacking in the canvas sizes based on window.innerHeight and also mucking with your css

Three.js not scaling or rotating Mesh on render()

I've been trying out Three.js today and I've had trouble getting my Mesh to change according using mesh.rotation.x += 10; for example.
The code below renders a triangle and the camera moves around onMouseMove but inside the render() function, it fails to scale or rotate the Mesh obj.
Appreciate the pointers.
<body>
<div id="container" style="border: #0f0 solid;">
</div>
<script type="text/javascript">
var mouseX = 0, mouseY = 0;
windowHalfX = window.innerWidth / 2,
windowHalfY = window.innerHeight / 2;
// get the DOM element to attach to
var container = document.getElementById("container");
// create a WebGL renderer, camera
// and a scene
var renderer = new THREE.WebGLRenderer();
renderer.setSize( window.innerWidth, window.innerHeight );
camera = new THREE.PerspectiveCamera( 25, window.innerWidth / window.innerHeight, 50, 1e7 );
var scene = new THREE.Scene();
var obj;
var geom = new THREE.Geometry();
var stats;
init();
animate();
function init(){
// the camera starts at 0,0,0 so pull it back
camera.position.z = 400;
// start the renderer
// attach the render-supplied DOM element
container.appendChild(renderer.domElement);
// create a new mesh with triangle geometry
// create the sphere's material
var material = new THREE.MeshLambertMaterial(
{
color: 0x00FF00
});
var v1 = new THREE.Vector3(50,0,0);
var v2 = new THREE.Vector3(50,100,0);
var v3 = new THREE.Vector3(0, 50, 0);
geom.vertices.push(new THREE.Vertex(v1));
geom.vertices.push(new THREE.Vertex(v2));
geom.vertices.push(new THREE.Vertex(v3));
geom.faces.push(new THREE.Face3(0,1,2));
geom.computeFaceNormals();
obj = new THREE.Mesh(geom, material);
obj.doubleSided = true;
obj.rotation.x = 0.1;
// add the obj to the scene
scene.addObject(obj);
// create a point light
var pointLight = new THREE.PointLight( 0xFFFFFF );
// set its position
pointLight.position.x = 0;
pointLight.position.y = 0;
pointLight.position.z = 600;
//pointLight.lookAt(obj);
// add to the scene
scene.add(pointLight);
ambientLight = new THREE.AmbientLight( 0xbbbbbb );
scene.add(ambientLight);
document.addEventListener( 'mousemove', onDocumentMouseMove, false );
stats = new Stats();
stats.domElement.style.position = 'absolute';
stats.domElement.style.top = '0px';
stats.domElement.style.zIndex = 100;
container.appendChild( stats.domElement );
// draw!
renderer.render(scene, camera);
}
function animate() {
requestAnimationFrame( animate );
render();
stats.update();
}
function onDocumentMouseMove(event) {
mouseX = event.clientX - windowHalfX;
mouseY = event.clientY - windowHalfY;
}
function render() {
camera.position.x += ( mouseX - camera.position.x ) * .05;
camera.position.y += ( - mouseY + 200 - camera.position.y ) * .05;
camera.lookAt( scene.position );
var time = Date.now() * 0.0015;
for ( var i = 0; i < scene.objects.length; i ++ ) {
scene.objects[ i ].rotation.y = time * ( i % 2 ? 1 : -1 );
}
obj.rotation.x += 20;
renderer.clear();
renderer.render( scene, camera );
}
</script>
</body>
From r45 scene.addObject(obj); must be now scene.add(obj);
See Three.js commit log:
2011 10 06 - r45 - Object/Scene.add*() and Object/Scene.remove*() are now Object/Scene.add() and Object/Scene.remove()

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