Object moving in different direction after rotating the plane, three js(v73) - three.js

Question

I am have having issue in moving the object, when using mouse. When i move the object initially it works fine, but after rotating the scene about the y-axis, the object starts moving in opposite direction of the mouse. I have created a jsfiddle for that. Here is the code:
//define global variables here
var container, renderer;
var camera, scene, projector,mouseVector,controls;
var mouseX, mouseY, draggable;
var pen,c_mesh,interactiveObj = [];
var cube_selected=false;
var wallWidth=1200;
var wallHeight=400;
var raycaster = new THREE.Raycaster(); // create once
var mouse = new THREE.Vector2(); // create once
init();
animate();
function init(){
container=document.createElement('div');
document.body.appendChild(container);
camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 10, 10000);
//camera.position.set(0,-wallWidth/2+10,wallWidth);
camera.position.set(0,-wallHeight/2+10,wallWidth);
// camera.lookAt(new THREE.Vector3(0,-wallWidth/2 +10,10));
//camera.lookAt(new THREE.Vector3(10,10,10));
scene = new THREE.Scene();
var ambient = new THREE.AmbientLight(0x666666);
scene.add(ambient);
//walls
walls = new THREE.Object3D();
var groundMat = new THREE.MeshPhongMaterial({color:0x808080});
var groundGeo_2 = new THREE.PlaneGeometry(wallWidth, wallWidth); //for roof and floor
var ground = new THREE.Mesh(groundGeo_2, groundMat);
ground.overdraw = true;
ground.position.set(0, -wallHeight, 0);
ground.rotation.x = -Math.PI/2;
walls.add(ground);
var cube_geometry = new THREE.CubeGeometry(500,300,100);
var c_material = new THREE.MeshNormalMaterial();
c_mesh = new THREE.Mesh(cube_geometry, c_material);
c_mesh.overdraw = true;
c_mesh.name = "first_cube";
c_mesh.position.set(0, -wallHeight+100/2-1 ,0); //c_mesh.add(camera);
c_mesh.rotation.x = Math.PI * 0.1;
interactiveObj.push(c_mesh);
walls.add(c_mesh);
scene.add(walls);
//projector = new THREE.Projector();
mouseVector = new THREE.Vector3();
renderer = new THREE.WebGLRenderer();
renderer.setSize(window.innerWidth, window.innerHeight);
renderer.shadowMapEnabled = true;
container.appendChild( renderer.domElement );
//IE, Chrome, Safari, Opera
document.addEventListener('mousewheel',onDocumentMouseWheel, false);
//Firefox
document.addEventListener('DOMMouseScroll', onDocumentMouseWheel, false);
document.addEventListener( 'mousemove', onDocumentMouseMove, false );
document.addEventListener('mousedown', onDocumentMouseDown, false);
document.addEventListener('mouseup', onDocumentMouseUp, false);
window.addEventListener( 'resize', onWindowResize, false );
}
function animate() {
requestAnimationFrame( animate );
render();
}
function render() {
renderer.render( scene, camera );
}
function onWindowResize() {
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize( window.innerWidth, window.innerHeight );
}
function onDocumentMouseDown(event){
draggable = true;
event.preventDefault();
mouse.x = ( event.clientX / renderer.domElement.width ) * 2 - 1;
mouse.y = - ( event.clientY / renderer.domElement.height ) * 2 + 1;
raycaster.setFromCamera( mouse, camera );
var intersects = raycaster.intersectObjects( interactiveObj, true );
console.log(intersects);
if ( intersects.length > 0 ) {
if(intersects[0].object == c_mesh) {
renderer.domElement.style.cursor = 'pointer';
console.log("cube selected "); cube_selected=true;
}else{
cube_selected=false;
}
draggable = false;
}
}
function onDocumentMouseUp(event){
draggable = false;
cube_selected=false;
renderer.domElement.style.cursor = 'auto';
}
function onDocumentMouseMove( event ) {
if(draggable){
if(mouseX != 0 && mouseY != 0){
deltaX = event.clientX - mouseX;
deltaY = event.clientY - mouseY;
walls.rotation.y += deltaX * 0.01;
walls.rotation.x += deltaY * 0.01;
}
}else if (cube_selected==true){
if(mouseX != 0 && mouseY != 0){
deltaX = event.clientX - mouseX;
deltaY = event.clientY - mouseY;
c_mesh.position.x += deltaX*1.5 ;
c_mesh.position.y -= deltaY*1.5 ;
}
}
mouseX = event.clientX;
mouseY = event.clientY;
render();
}
function onDocumentMouseWheel( event ) {
mouseDelta = (-event.wheelDeltaY|| event.detail);
camera.position.z += mouseDelta * 1 ;
// console.log("camera position : "+ camera.position.z);
render();
}
https://jsfiddle.net/pn1pL4jb/5/
What i have done:
Added object in plane, rather then to scene because I want the same rotation of plane and object in the same direction.

Answer 1

The problem was that when you rotated the walls/ground with the mouse drag, the cube's rotation was not updated to match. So when you went to drag the cube after a world rotation, the cube is still operating in its old coordinate system. Also, be careful how you add children to parents. The cube should be a child of the scene (or world coordinate system) if you intend to move it all around. If it is a child of the floor or walls, things can get wacky really fast. :)
I updated your JSFiddle as well as cleaned up the code a little bit:
https://jsfiddle.net/aucyekux/
The magic is happening on line 126 with the copying of the wall's rotation into the cube's rotation so it matches:
c_mesh.rotation.copy(walls.rotation);
I won't assume how much 3D math you know, but I'll just say that copying the ground's rotation essentially creates a new frame of reference or local coordinate system for the cube so that when you drag it to the right, and the code says x = x + ... , its new coordinate system has its x direction pointing in the same direction as the ground/walls' new x direction (after the rotation you performed on them).
Hope this makes sense - don't worry if you don't quite get how it all works. I am a veteran 3D game programmer hobbyist for 20 years and I still sometimes forget how this all works and I have struggled with it plenty. I also refresh my understanding by browsing scratchapixel (the 3D math / coordinate system primer section) every now and then. It keeps all this 3D math stuff fresh. Good luck to you! :)

Answer 2

The following is a 2nd answer to this problem. The OP has added orbitControls.js to his app and now all the objects are more manageable. Here is the whole app's .html file, updated to reflect the changes. Now, you can click/drag to rotate the whole room. And then you can click/drag on the chair or the sofa and drag them around the room. Their Y positions are clamped to the ground (0.0) so that they do not incorrectly penetrate the floor.
The sliding of objects along the floor is achieved through raycasting against just the ground (when the mouse has selected them and dragging them). The raycast returns the intersection point in world space, so I just copy that into the draggable objects' position. Then a post-clamp of their Y positions prevent them from falling through the floor.
Even better, is the fact that we don't need localToWorld and worldToLocal matrix 'hacks' anymore because everything is relative to the Scene, which is how it is in real life. :) To prove this, I added an example update the chair's rotation around its own Y axis, so we have a spinning chair that is able to rotate around its own local center of gravity, while also being able to move its position relative to the Scene (world).
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/html">
<head lang="en">
<meta charset="UTF-8">
<title>Room</title>
</head>
<body>
<script src="http://alexan0308.github.io/threejs/build/three.min.js"></script>
<script src="http://alexan0308.github.io/threejs/examples/js/loaders/OBJLoader.js"></script>
<script src="http://alexan0308.github.io/threejs/examples/js/loaders/MTLLoader.js"></script>
<script src="http://alexan0308.github.io/threejs/examples/js/loaders/OBJMTLLoader.js"></script>
<script src="http://threejs.org/examples/js/controls/OrbitControls.js"></script>
<div id="workspace"></div>
<script>
//define global variables here
var container, renderer;
var camera, scene, projector, mouseVector, controls;
var mouseX, mouseY, draggable;
var pen, c_mesh, interactiveObj = [], rotateObj = [], groundRaycastObj = [];
var wallWidth = 1200;
var wallHeight = 400;
var chair_model, sofa_model;
var chair_selected = false;
var sofa_selected = false;
var raycaster;
var mouse = new THREE.Vector2(), INTERSECTED;
var radius = 100, theta = 0;
var oldIntersectPoint = new THREE.Vector3();
var newIntersectPoint = new THREE.Vector3();
var intersectOffset = new THREE.Vector3();
var chair_rotate = false;
var walls;
var mesh_box;
var wallright, wallleft, wallback, wallfront, ceiling, ground;
var strDownloadMime = "image/octet-stream";
init();
animate();
function init() {
container = document.getElementById('workspace'); //document.createElement('div');
document.body.appendChild(container);
//camera
//camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 10, 10000);
// camera.position.set(0, -wallHeight / 2 + 10, wallWidth);
// camera.lookAt(new THREE.Vector3(10, 10, 10));
//renderer
renderer = new THREE.WebGLRenderer({preserveDrawingBuffer: true});
renderer.setSize(window.innerWidth, window.innerHeight);
renderer.setClearColor(0x889988);
renderer.shadowMapEnabled = true;
container.appendChild(renderer.domElement);
scene = new THREE.Scene();
raycaster = new THREE.Raycaster();
var ambient = new THREE.AmbientLight(0xffffff);
scene.add(ambient);
camera = new THREE.PerspectiveCamera( 60, window.innerWidth / window.innerHeight, 1, 10000 );
camera.position.z= wallWidth;
camera.position.y= wallWidth/2;
controls = new THREE.OrbitControls( camera, renderer.domElement );
//controls.addEventListener( 'change', render ); // add this only if there is no animation loop (requestAnimationFrame)
controls.enableDamping = true;
controls.dampingFactor = 0.25;
//controls.enableZoom = false;
//walls
walls = new THREE.Object3D();
var groundGeo_2 = new THREE.PlaneGeometry(wallWidth, wallWidth); //for roof and floor
var groundGeo = new THREE.PlaneGeometry(wallWidth, wallHeight);
var wallTextureRight = new THREE.MeshBasicMaterial({
map: THREE.ImageUtils.loadTexture('textures/walls/rainbow.jpg')
});
wallTextureRight.map.needsUpdate = true;
var wallTextureLeft = new THREE.MeshBasicMaterial({
map: THREE.ImageUtils.loadTexture('textures/walls/rainbow.jpg')
});
var wallTextureFront = new THREE.MeshBasicMaterial({
map: THREE.ImageUtils.loadTexture('textures/walls/wall4.jpg')
});
var wallTextureBack = new THREE.MeshBasicMaterial({
map: THREE.ImageUtils.loadTexture('textures/walls/wall3.png')
});
var floorTexture = new THREE.MeshBasicMaterial({
map: THREE.ImageUtils.loadTexture('textures/walls/floor.jpg')
});
floorTexture.map.needsUpdate = true;
var ceilTexture = new THREE.MeshBasicMaterial({
map: THREE.ImageUtils.loadTexture('textures/walls/wall4.jpg')
});
ground = new THREE.Mesh(groundGeo_2, floorTexture);
ground.overdraw = true;
ground.position.set(0, 0, 0);
ground.rotation.x = -Math.PI / 2;
walls.add(ground);
console.log(ground);
wallleft = new THREE.Mesh(groundGeo, wallTextureLeft);
wallleft.overdraw = true;
wallleft.position.set(-wallWidth / 2, wallHeight / 2, 0);
wallleft.rotation.y = Math.PI / 2;
walls.add(wallleft);
wallright = new THREE.Mesh(groundGeo, wallTextureRight);
wallright.overdraw = true;
wallright.position.set(wallWidth / 2, wallHeight / 2, 0);
wallright.rotation.y = -Math.PI / 2;
walls.add(wallright);
wallback = new THREE.Mesh(groundGeo, wallTextureBack);
wallback.overdraw = true;
wallback.position.set(0, wallHeight / 2, -wallWidth / 2);
walls.add(wallback);
wallfront = new THREE.Mesh(groundGeo, wallTextureFront);
wallfront.overdraw = true;
wallfront.position.set(0, wallHeight / 2, wallWidth / 2);
wallfront.rotation.y = -Math.PI;
walls.add(wallfront);
ceiling = new THREE.Mesh(groundGeo_2, ceilTexture);
ceiling.position.set(0, wallHeight, 0);
ceiling.rotation.x = Math.PI / 2;
walls.add(ceiling);
scene.add(walls);
groundRaycastObj.push(walls);
//load bed texture
var bed_texture = new THREE.ImageUtils.loadTexture("textures/cb-rochelle-gray_baked.png");
var bedMaterial = new THREE.MeshBasicMaterial({
map: bed_texture,
side: THREE.DoubleSide
});
//load bed
var loader = new THREE.JSONLoader();
loader.load('js/sofa.js', function (geometry) {
sofa_model = new THREE.Mesh(geometry, bedMaterial);
for (var i = 0; i < sofa_model.children.length; i++) {
sofa_model.children[i].material = material;
sofa_model.children[i].userDataParent = sofa_model;
sofa_model.children[i].name = 'sofa_model';
}
sofa_model.position.set(200,0, -200);
sofa_model.rotation.set(0, 0, 0);
sofa_model.scale.set(3, 3, 3);
sofa_model.name = 'sofa_model';
interactiveObj.push(sofa_model);
scene.add(sofa_model);
});
//load chair texture
var chair_texture = new THREE.ImageUtils.loadTexture("textures/chair.png");
var chairMaterial = new THREE.MeshBasicMaterial({
map: chair_texture,
side: THREE.DoubleSide
});
//load chair
var loader = new THREE.JSONLoader();
loader.load('js/chair_model.js', function (geometry) {
chair_model = new THREE.Mesh(geometry, chairMaterial);
for (var i = 0; i < chair_model.children.length; i++) {
chair_model.children[i].material = material;
chair_model.children[i].userDataParent = sofa_model;
chair_model.children[i].name = 'chair_model';
}
chair_model.position.set(-200,0, -200);
chair_model.rotation.set(0, 0, 0);
chair_model.scale.set(3, 3, 3);
chair_model.name = 'chair_model';
interactiveObj.push(chair_model);
scene.add(chair_model);
});
//IE, Chrome, Safari, Opera
document.addEventListener('mousewheel', onDocumentMouseWheel, false);
//Firefox
document.addEventListener('DOMMouseScroll', onDocumentMouseWheel, false);
document.addEventListener('mousemove', onDocumentMouseMove, false);
document.addEventListener('mousedown', onDocumentMouseDown, false);
document.addEventListener('mouseup', onDocumentMouseUp, false);
window.addEventListener('resize', onWindowResize, false);
}
function animate() {
requestAnimationFrame(animate);
chair_model.rotation.y += 0.02;
controls.update();
// Render the frame
//Don't render twice, it will slow down your animation!
//render();
renderer.render(scene, camera);
}
function render() {
renderer.render(scene, camera);
}
function onWindowResize() {
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize(window.innerWidth, window.innerHeight);
//controls.handleResize();
}
function onDocumentMouseDown(event) {
draggable = true;
event.preventDefault();
var testIntersects;
testIntersects = raycaster.intersectObjects(groundRaycastObj, true);
if (testIntersects.length > 0)
oldIntersectPoint.copy(testIntersects[0].point);
// find intersections
raycaster.setFromCamera(mouse, camera);
var intersects = raycaster.intersectObjects(interactiveObj, true);
if (intersects.length > 0) {
controls.enabled=false;
if (intersects[0].object.name == 'chair_model') {
container.style.cursor = 'pointer';
chair_selected = true;
} else if (intersects[0].object.name == 'sofa_model') {
container.style.cursor = 'pointer';
sofa_selected = true;
}
else {
chair_selected = false;
sofa_selected = false;
}
draggable = false;
}
}
function onDocumentMouseUp(event) {
draggable = false;
chair_selected = false;
sofa_selected = false;
chair_rotate = false;
container.style.cursor = 'auto';
controls.enabled=true;
oldIntersectPoint.set(0,0,0);
newIntersectPoint.set(0,0,0);
intersectOffset.set(0,0,0);
}
function onDocumentMouseMove(event) {
mouse.x = ( event.clientX / window.innerWidth ) * 2 - 1;
mouse.y = -( event.clientY / window.innerHeight ) * 2 + 1;
var deltaX = event.clientX - mouseX;
var deltaY = event.clientY - mouseY;
var testIntersects;
raycaster.setFromCamera(mouse, camera);
var intersects = raycaster.intersectObjects(interactiveObj, true);
if (intersects.length > 0) {
container.style.cursor = 'pointer';
//addRotationLine(intersects[0].object);
} else {
container.style.cursor = 'auto';
}
if (draggable) {
} else if (chair_selected == true) {
testIntersects = raycaster.intersectObjects(groundRaycastObj, true);
if (testIntersects.length > 0) {
newIntersectPoint.copy(testIntersects[0].point);
intersectOffset.copy(newIntersectPoint);
intersectOffset.sub(oldIntersectPoint);
//uncomment below if you want more precision mouse movements of objects
//intersectOffset.multiplyScalar(0.1);
oldIntersectPoint.copy(newIntersectPoint);
chair_model.position.add(intersectOffset);
}
// clamp chair position to the ground
chair_model.position.y = 0;
} else if (chair_rotate == true) {
rotate_object(chair_model, event);
}
else if (sofa_selected == true) {
testIntersects = raycaster.intersectObjects(groundRaycastObj, true);
if (testIntersects.length > 0) {
newIntersectPoint.copy(testIntersects[0].point);
intersectOffset.copy(newIntersectPoint);
intersectOffset.sub(oldIntersectPoint);
//uncomment below if you want more precision mouse movements of objects
//intersectOffset.multiplyScalar(0.1);
oldIntersectPoint.copy(newIntersectPoint);
sofa_model.position.add(intersectOffset);
}
// clamp sofa position to the ground
sofa_model.position.y = 0;
}
mouseX = event.clientX;
mouseY = event.clientY;
//render(); // no need to render
}
function onDocumentMouseWheel(event) {
// This is automatically handled for you by orbitControls.js,
// but you can't disable zoom on the controls - so don't type controls.enableZoom = false;
//mouseDelta = (-event.wheelDeltaY || event.detail);
//camera.position.z += mouseDelta * 1;
//render(); // no need to render
}
function addRotationLine(objModel) {
var material = new THREE.LineBasicMaterial({
color: 0x0000ff,
linewidth: 6
});
var geometry = new THREE.Geometry();
geometry.vertices.push(
new THREE.Vector3(-10, 500, 0),
new THREE.Vector3(1000, 500, 0)
);
var line = new THREE.Line(geometry, material);
objModel.add(line);
}
function rotate_object(object, event) {
mouse.x = ( event.clientX / window.innerWidth ) * 2 - 1;
mouse.y = -( event.clientY / window.innerHeight ) * 2 + 1;
var deltaX = event.clientX - mouseX;
var deltaY = event.clientY - mouseY;
object.rotation.y += deltaX * 0.02;
object.rotation.y += deltaY * 0.01;
}
</script>
</body>
</html>

Answer 3

Change line 143 of the fiddle to:
c_mesh.position.x += deltaX*1.5 * Math.cos( walls.rotation.y);
When you rotate the scene, the plane the mouse moves on doesn't rotate with it. So you have to act like it does by scaling by the cosine of the rotation.