three
Version:
JavaScript 3D library
450 lines (314 loc) • 10.8 kB
JavaScript
import {
Matrix4,
Object3D,
Quaternion,
Vector3
} from 'three';
// Based on http://www.emagix.net/academic/mscs-project/item/camera-sync-with-css3-and-webgl-threejs
const _position = new Vector3();
const _quaternion = new Quaternion();
const _scale = new Vector3();
/**
* The base 3D object that is supported by {@link CSS3DRenderer}.
*
* @augments Object3D
*/
class CSS3DObject extends Object3D {
/**
* Constructs a new CSS3D object.
*
* @param {DOMElement} [element] - The DOM element.
*/
constructor( element = document.createElement( 'div' ) ) {
super();
/**
* This flag can be used for type testing.
*
* @type {boolean}
* @readonly
* @default true
*/
this.isCSS3DObject = true;
/**
* The DOM element which defines the appearance of this 3D object.
*
* @type {DOMElement}
* @readonly
* @default true
*/
this.element = element;
this.element.style.position = 'absolute';
this.element.style.pointerEvents = 'auto';
this.element.style.userSelect = 'none';
this.element.setAttribute( 'draggable', false );
this.addEventListener( 'removed', function () {
this.traverse( function ( object ) {
if (
object.element instanceof object.element.ownerDocument.defaultView.Element &&
object.element.parentNode !== null
) {
object.element.remove();
}
} );
} );
}
copy( source, recursive ) {
super.copy( source, recursive );
this.element = source.element.cloneNode( true );
return this;
}
}
/**
* A specialized version of {@link CSS3DObject} that represents
* DOM elements as sprites.
*
* @augments CSS3DObject
*/
class CSS3DSprite extends CSS3DObject {
/**
* Constructs a new CSS3D sprite object.
*
* @param {DOMElement} [element] - The DOM element.
*/
constructor( element ) {
super( element );
/**
* This flag can be used for type testing.
*
* @type {boolean}
* @readonly
* @default true
*/
this.isCSS3DSprite = true;
/**
* The sprite's rotation in radians.
*
* @type {number}
* @default 0
*/
this.rotation2D = 0;
}
copy( source, recursive ) {
super.copy( source, recursive );
this.rotation2D = source.rotation2D;
return this;
}
}
//
const _matrix = new Matrix4();
const _matrix2 = new Matrix4();
/**
* This renderer can be used to apply hierarchical 3D transformations to DOM elements
* via the CSS3 [transform]{@link https://www.w3schools.com/cssref/css3_pr_transform.asp} property.
* `CSS3DRenderer` is particularly interesting if you want to apply 3D effects to a website without
* canvas based rendering. It can also be used in order to combine DOM elements with WebGLcontent.
*
* There are, however, some important limitations:
*
* - It's not possible to use the material system of *three.js*.
* - It's also not possible to use geometries.
* - The renderer only supports 100% browser and display zoom.
*
* So `CSS3DRenderer` is just focused on ordinary DOM elements. These elements are wrapped into special
* 3D objects ({@link CSS3DObject} or {@link CSS3DSprite}) and then added to the scene graph.
*/
class CSS3DRenderer {
/**
* Constructs a new CSS3D renderer.
*
* @param {CSS3DRenderer~Parameters} [parameters] - The parameters.
*/
constructor( parameters = {} ) {
const _this = this;
let _width, _height;
let _widthHalf, _heightHalf;
const cache = {
camera: { style: '' },
objects: new WeakMap()
};
const domElement = parameters.element !== undefined ? parameters.element : document.createElement( 'div' );
domElement.style.overflow = 'hidden';
/**
* The DOM where the renderer appends its child-elements.
*
* @type {DOMElement}
*/
this.domElement = domElement;
const viewElement = document.createElement( 'div' );
viewElement.style.transformOrigin = '0 0';
viewElement.style.pointerEvents = 'none';
domElement.appendChild( viewElement );
const cameraElement = document.createElement( 'div' );
cameraElement.style.transformStyle = 'preserve-3d';
viewElement.appendChild( cameraElement );
/**
* Returns an object containing the width and height of the renderer.
*
* @return {{width:number,height:number}} The size of the renderer.
*/
this.getSize = function () {
return {
width: _width,
height: _height
};
};
/**
* Renders the given scene using the given camera.
*
* @param {Object3D} scene - A scene or any other type of 3D object.
* @param {Camera} camera - The camera.
*/
this.render = function ( scene, camera ) {
const fov = camera.projectionMatrix.elements[ 5 ] * _heightHalf;
if ( camera.view && camera.view.enabled ) {
// view offset
viewElement.style.transform = `translate( ${ - camera.view.offsetX * ( _width / camera.view.width ) }px, ${ - camera.view.offsetY * ( _height / camera.view.height ) }px )`;
// view fullWidth and fullHeight, view width and height
viewElement.style.transform += `scale( ${ camera.view.fullWidth / camera.view.width }, ${ camera.view.fullHeight / camera.view.height } )`;
} else {
viewElement.style.transform = '';
}
if ( scene.matrixWorldAutoUpdate === true ) scene.updateMatrixWorld();
if ( camera.parent === null && camera.matrixWorldAutoUpdate === true ) camera.updateMatrixWorld();
let tx, ty;
if ( camera.isOrthographicCamera ) {
tx = - ( camera.right + camera.left ) / 2;
ty = ( camera.top + camera.bottom ) / 2;
}
const scaleByViewOffset = camera.view && camera.view.enabled ? camera.view.height / camera.view.fullHeight : 1;
const cameraCSSMatrix = camera.isOrthographicCamera ?
`scale( ${ scaleByViewOffset } )` + 'scale(' + fov + ')' + 'translate(' + epsilon( tx ) + 'px,' + epsilon( ty ) + 'px)' + getCameraCSSMatrix( camera.matrixWorldInverse ) :
`scale( ${ scaleByViewOffset } )` + 'translateZ(' + fov + 'px)' + getCameraCSSMatrix( camera.matrixWorldInverse );
const perspective = camera.isPerspectiveCamera ? 'perspective(' + fov + 'px) ' : '';
const style = perspective + cameraCSSMatrix +
'translate(' + _widthHalf + 'px,' + _heightHalf + 'px)';
if ( cache.camera.style !== style ) {
cameraElement.style.transform = style;
cache.camera.style = style;
}
renderObject( scene, scene, camera, cameraCSSMatrix );
};
/**
* Resizes the renderer to the given width and height.
*
* @param {number} width - The width of the renderer.
* @param {number} height - The height of the renderer.
*/
this.setSize = function ( width, height ) {
_width = width;
_height = height;
_widthHalf = _width / 2;
_heightHalf = _height / 2;
domElement.style.width = width + 'px';
domElement.style.height = height + 'px';
viewElement.style.width = width + 'px';
viewElement.style.height = height + 'px';
cameraElement.style.width = width + 'px';
cameraElement.style.height = height + 'px';
};
function epsilon( value ) {
return Math.abs( value ) < 1e-10 ? 0 : value;
}
function getCameraCSSMatrix( matrix ) {
const elements = matrix.elements;
return 'matrix3d(' +
epsilon( elements[ 0 ] ) + ',' +
epsilon( - elements[ 1 ] ) + ',' +
epsilon( elements[ 2 ] ) + ',' +
epsilon( elements[ 3 ] ) + ',' +
epsilon( elements[ 4 ] ) + ',' +
epsilon( - elements[ 5 ] ) + ',' +
epsilon( elements[ 6 ] ) + ',' +
epsilon( elements[ 7 ] ) + ',' +
epsilon( elements[ 8 ] ) + ',' +
epsilon( - elements[ 9 ] ) + ',' +
epsilon( elements[ 10 ] ) + ',' +
epsilon( elements[ 11 ] ) + ',' +
epsilon( elements[ 12 ] ) + ',' +
epsilon( - elements[ 13 ] ) + ',' +
epsilon( elements[ 14 ] ) + ',' +
epsilon( elements[ 15 ] ) +
')';
}
function getObjectCSSMatrix( matrix ) {
const elements = matrix.elements;
const matrix3d = 'matrix3d(' +
epsilon( elements[ 0 ] ) + ',' +
epsilon( elements[ 1 ] ) + ',' +
epsilon( elements[ 2 ] ) + ',' +
epsilon( elements[ 3 ] ) + ',' +
epsilon( - elements[ 4 ] ) + ',' +
epsilon( - elements[ 5 ] ) + ',' +
epsilon( - elements[ 6 ] ) + ',' +
epsilon( - elements[ 7 ] ) + ',' +
epsilon( elements[ 8 ] ) + ',' +
epsilon( elements[ 9 ] ) + ',' +
epsilon( elements[ 10 ] ) + ',' +
epsilon( elements[ 11 ] ) + ',' +
epsilon( elements[ 12 ] ) + ',' +
epsilon( elements[ 13 ] ) + ',' +
epsilon( elements[ 14 ] ) + ',' +
epsilon( elements[ 15 ] ) +
')';
return 'translate(-50%,-50%)' + matrix3d;
}
function hideObject( object ) {
if ( object.isCSS3DObject ) object.element.style.display = 'none';
for ( let i = 0, l = object.children.length; i < l; i ++ ) {
hideObject( object.children[ i ] );
}
}
function renderObject( object, scene, camera, cameraCSSMatrix ) {
if ( object.visible === false ) {
hideObject( object );
return;
}
if ( object.isCSS3DObject ) {
const visible = ( object.layers.test( camera.layers ) === true );
const element = object.element;
element.style.display = visible === true ? '' : 'none';
if ( visible === true ) {
object.onBeforeRender( _this, scene, camera );
let style;
if ( object.isCSS3DSprite ) {
// http://swiftcoder.wordpress.com/2008/11/25/constructing-a-billboard-matrix/
_matrix.copy( camera.matrixWorldInverse );
_matrix.transpose();
if ( object.rotation2D !== 0 ) _matrix.multiply( _matrix2.makeRotationZ( object.rotation2D ) );
object.matrixWorld.decompose( _position, _quaternion, _scale );
_matrix.setPosition( _position );
_matrix.scale( _scale );
_matrix.elements[ 3 ] = 0;
_matrix.elements[ 7 ] = 0;
_matrix.elements[ 11 ] = 0;
_matrix.elements[ 15 ] = 1;
style = getObjectCSSMatrix( _matrix );
} else {
style = getObjectCSSMatrix( object.matrixWorld );
}
const cachedObject = cache.objects.get( object );
if ( cachedObject === undefined || cachedObject.style !== style ) {
element.style.transform = style;
const objectData = { style: style };
cache.objects.set( object, objectData );
}
if ( element.parentNode !== cameraElement ) {
cameraElement.appendChild( element );
}
object.onAfterRender( _this, scene, camera );
}
}
for ( let i = 0, l = object.children.length; i < l; i ++ ) {
renderObject( object.children[ i ], scene, camera, cameraCSSMatrix );
}
}
}
}
/**
* Constructor parameters of `CSS3DRenderer`.
*
* @typedef {Object} CSS3DRenderer~Parameters
* @property {DOMElement} [element] - A DOM element where the renderer appends its child-elements.
* If not passed in here, a new div element will be created.
**/
export { CSS3DObject, CSS3DSprite, CSS3DRenderer };