CODEWITHSUNDEEP
javascriptthree.js
Catherine Hwang
Catherine Hwang

Reputation: 1030

ThreeJS Rotation Animation

I have a cube in ThreeJS and I would like to rotate it 90 degrees clockwise every time I press a button. I think I have the basic gist of it: create a Three.Animation instance, bind it to the cube, and then have the animation begin every time I press the correct button. However, I'm having a difficult time understanding ThreeJS's API, because it doesn't seem to contain any examples for its methods.

This is THREE.js's Animation constructor: ( root, data, interpolationType, JITCompile ) I don't understand what goes into the fields. I'm guessing root would be where I put my cube, but what about the rest?

Also can I just call animation.play() to cause the animation whenever I want? And how does the animationHandler work?

Upvotes: 5

Views: 13424

Answers (1)

George Profenza
George Profenza

Reputation: 51837

I think for for rotating an object 90 degrees clockwise, using the TWEEN class will do. I think the Animation class is handy for heavier stuff (like bones/skin morphs/etc.)

To use the tween class there are 3 basic steps:

  1. include the class in your file (<script src="js/Tween.js"></script>)
  2. add your tween for the event you need (new TWEEN.Tween( cube.rotation ).to( { y:Math.random()}, 1000 ).easing( TWEEN.Easing.Quadratic.EaseOut).start();)
  3. update the tween in your render loop (TWEEN.update();)

You can have a have a look at the cubes tween example for a start.

I've modified the default cube example to have the tween in:

three.js cube tween

<!doctype html>
<html lang="en">
    <head>
        <title>three.js canvas - geometry - cube</title>
        <meta charset="utf-8">
        <meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
        <style>
            body {
                font-family: Monospace;
                background-color: #f0f0f0;
                margin: 0px;
                overflow: hidden;
            }
        </style>
    </head>
    <body>

        <script src="../build/Three.js"></script>
        <script src="js/Tween.js"></script>
        <script src="js/RequestAnimationFrame.js"></script>
        <script src="js/Stats.js"></script>

        <script>

            var container, stats;

            var camera, scene, renderer;

            var cube, plane;

            var windowHalfX = window.innerWidth / 2;
            var windowHalfY = window.innerHeight / 2;

            var rad90 = Math.PI * .5;

            init();
            animate();

            function init() {

                container = document.createElement( 'div' );
                document.body.appendChild( container );

                var info = document.createElement( 'div' );
                info.style.position = 'absolute';
                info.style.top = '10px';
                info.style.width = '100%';
                info.style.textAlign = 'center';
                info.innerHTML = 'click to tween';
                container.appendChild( info );

                camera = new THREE.PerspectiveCamera( 70, window.innerWidth / window.innerHeight, 1, 1000 );
                camera.position.y = 150;
                camera.position.z = 500;

                scene = new THREE.Scene();

                // Cube

                var materials = [];

                for ( var i = 0; i < 6; i ++ ) {

                    materials.push( [ new THREE.MeshBasicMaterial( { color: Math.random() * 0xffffff } ) ] );

                }

                cube = new THREE.Mesh( new THREE.CubeGeometry( 200, 200, 200, 1, 1, 1, materials ), new THREE.MeshFaceMaterial() );
                cube.position.y = 150;
                cube.overdraw = true;
                scene.add( cube );

                // Plane

                plane = new THREE.Mesh( new THREE.PlaneGeometry( 200, 200 ), new THREE.MeshBasicMaterial( { color: 0xe0e0e0 } ) );
                plane.rotation.x = - 90 * ( Math.PI / 180 );
                plane.overdraw = true;
                scene.add( plane );

                renderer = new THREE.CanvasRenderer();
                renderer.setSize( window.innerWidth, window.innerHeight );

                container.appendChild( renderer.domElement );

                stats = new Stats();
                stats.domElement.style.position = 'absolute';
                stats.domElement.style.top = '0px';
                container.appendChild( stats.domElement );

                document.addEventListener( 'mousedown', onDocumentMouseDown, false );
            }

            //

            function onDocumentMouseDown( event ) {

                event.preventDefault();
                new TWEEN.Tween( cube.rotation ).to( {  y:  cube.rotation.y + rad90}, 1000 ).easing( TWEEN.Easing.Quadratic.EaseOut).start();
                new TWEEN.Tween( plane.rotation ).to( { z:  plane.rotation.z + rad90}, 1000 ).easing( TWEEN.Easing.Quadratic.EaseOut).start();

                console.log("click");
            }

            //

            function animate() {

                requestAnimationFrame( animate );

                render();
                stats.update();

            }

            function render() {
                TWEEN.update();
                renderer.render( scene, camera );

            }

        </script>

    </body>
</html>

Upvotes: 12

Related Questions