I made a canvas with shapes in it…the shapes are draggable.
Everything seems to work fine…But now I’m trying to figure out
how can I detect what shape was selected/dragged?
this is my code: (Javascript)
var container, stats;
var camera, scene, projector, renderer;
var objects = [], plane;
var mouse = new THREE.Vector2(),
offset = new THREE.Vector3(),
INTERSECTED, SELECTED;
var basic_x_dist = 0;
var cameraX = 0,cameraY = 0,cameraZ = 100; // default-same as camera.position.z!
init();
animate();
function init() {
container = document.createElement( 'div' );
document.body.appendChild( container );
camera = new THREE.PerspectiveCamera( 70, window.innerWidth / window.innerHeight, 1, 500 );
camera.position.z = 300;
scene = new THREE.Scene();
scene.add( new THREE.AmbientLight( 0x505050 ) );
var light = new THREE.SpotLight( 0xffffff, 1.5 );
light.position.set( 0, 500, 2000 );
light.castShadow = true;
scene.add( light );
var geometry = new THREE.CubeGeometry( 7, 7, 1, 3, 3, 1);
for ( var i = 0; i < 5; i ++ ) {
var object = new THREE.Mesh( geometry, new THREE.MeshLambertMaterial( { map: THREE.ImageUtils.loadTexture( 'red.png' ) } ) );
//object.material.ambient = object.material.color;
object.position.x = basic_x_dist;
basic_x_dist += 10;
//object.position.x = Math.random() * 100 - 50;
//object.position.y = Math.random() * 60 - 30;
//object.position.z = Math.random() * 80 - 40;
//object.rotation.x = ( Math.random() * 360 ) * Math.PI / 180;
//object.rotation.y = ( Math.random() * 360 ) * Math.PI / 180;
//object.rotation.z = ( Math.random() * 360 ) * Math.PI / 180;
//object.scale.x = Math.random() * 2 + 1;
//object.scale.y = Math.random() * 2 + 1;
//object.scale.z = Math.random() * 2 + 1;
//object.castShadow = true;
//object.receiveShadow = true;
scene.add( object );
objects.push( object );
}
plane = new THREE.Mesh( new THREE.PlaneGeometry( 2000, 2000, 8, 8 ), new THREE.MeshBasicMaterial( { color: 0x000000, opacity: 0.25, transparent: true, wireframe: true } ) );
plane.lookAt( camera.position );
plane.visible = false;
scene.add( plane );
projector = new THREE.Projector();
renderer = new THREE.CanvasRenderer();
renderer.sortObjects = false;
renderer.setSize( window.innerWidth, window.innerHeight );
//renderer.shadowMapEnabled = true;
//renderer.shadowMapSoft = true;
//renderer.shadowCameraNear = 3;
//renderer.shadowCameraFar = camera.far;
//renderer.shadowCameraFov = 50;
//renderer.shadowMapBias = 0.0039;
//renderer.shadowMapDarkness = 0.5;
//renderer.shadowMapWidth = 1024;
//renderer.shadowMapHeight = 1024;
container.appendChild( renderer.domElement );
var info = document.createElement( 'div' );
info.style.position = 'absolute';
info.style.top = '10px';
info.style.width = '100%';
info.style.textAlign = 'center';
info.innerHTML = '<a href="http://github.com/mrdoob/three.js" target="_blank">three.js</a> webgl - draggable cubes';
container.appendChild( info );
stats = new Stats();
stats.domElement.style.position = 'absolute';
stats.domElement.style.top = '0px';
container.appendChild( stats.domElement );
renderer.domElement.addEventListener( 'mousemove', onDocumentMouseMove, false );
renderer.domElement.addEventListener( 'mousedown', onDocumentMouseDown, false );
renderer.domElement.addEventListener( 'mouseup', onDocumentMouseUp, false );
document.onkeypress=key_event;
}
function onDocumentMouseMove( event ) {
event.preventDefault();
mouse.x = ( event.clientX / window.innerWidth ) * 2 - 1;
mouse.y = - ( event.clientY / window.innerHeight ) * 2 + 1;
var vector = new THREE.Vector3( mouse.x, mouse.y, 0.5 );
projector.unprojectVector( vector, camera );
var ray = new THREE.Ray( camera.position, vector.subSelf( camera.position ).normalize() );
if ( SELECTED ) {
var intersects = ray.intersectObject( plane );
SELECTED.position.copy( intersects[ 0 ].point.subSelf( offset ) );
return;
}
var intersects = ray.intersectObjects( objects );
if ( intersects.length > 0 ) {
if ( INTERSECTED != intersects[ 0 ].object ) {
if ( INTERSECTED ) INTERSECTED.material.color.setHex( INTERSECTED.currentHex );
INTERSECTED = intersects[ 0 ].object;
INTERSECTED.currentHex = INTERSECTED.material.color.getHex();
plane.position.copy( INTERSECTED.position );
}
container.style.cursor = 'pointer';
} else {
if ( INTERSECTED ) INTERSECTED.material.color.setHex( INTERSECTED.currentHex );
INTERSECTED = null;
container.style.cursor = 'auto';
}
}
function onDocumentMouseDown( event ) {
event.preventDefault();
var vector = new THREE.Vector3( mouse.x, mouse.y, 0.5 );
projector.unprojectVector( vector, camera );
var ray = new THREE.Ray( camera.position, vector.subSelf( camera.position ).normalize() );
var intersects = ray.intersectObjects( objects );
if ( intersects.length > 0 ) {
SELECTED = intersects[ 0 ].object;
var intersects = ray.intersectObject( plane );
offset.copy( intersects[ 0 ].point ).subSelf( plane.position );
container.style.cursor = 'move';
}
}
function onDocumentMouseUp( event ) {
event.preventDefault();
if ( INTERSECTED ) {
plane.position.copy( INTERSECTED.position );
SELECTED = null;
}
container.style.cursor = 'auto';
}
function rotateLeft(){
cameraX += 5;
}
function rotateRight(){
cameraX -= 5;
}
function rotateUp(){
cameraY += 5;
}
function rotateDown(){
cameraY -= 5;
}
function zoomIn(){
cameraZ += 5;
}
function zoomOut(){
cameraZ -= 5;
}
function showPositions(){
for(var i=0; i<5; i++){
alert(objects[i].position.x);
alert(objects[i].position.y);
alert(objects[i].position.z);
}
}
function key_event( event ) {
var unicode=event.keyCode? event.keyCode : event.charCode;
//alert(unicode); // find the char code
switch(unicode){
case 97: rotateLeft(); break;
case 100: rotateRight(); break;
case 119: rotateUp(); break;
case 120: rotateDown(); break;
case 122: zoomIn(); break;
case 99: zoomOut(); break;
case 115: showPositions(); break;
}
}
function animate() {
requestAnimationFrame( animate );
render();
stats.update();
}
function render() {
camera.position.x = cameraX; // updating the camera view-x scale after events
camera.position.y = cameraY; // updating the camera view-y scale after events
camera.position.z = cameraZ; // updating the camera view-z scale after events
camera.lookAt( scene.position );
renderer.render( scene, camera );
}
I found pretty simple solution…but I guess that’s the way it always works 🙂 All you have to do for the detection is 2 things: First of all add another variable: var thisObject; After that you have to go to the onMouseDown() function. Right after the SELECTED = intersects[0].object; you have to write this thing:
…Now thisObject holds the index of the current shape (that was selected/dragged) in objects array…yeah that simple 🙂