source: other-projects/playing-in-the-street/summer-2013/trunk/Playing-in-the-Street-WPF/Content/Web/mrdoob-three.js-4862f5f/src/extras/cameras/CombinedCamera.js@ 28897

/**
 *  @author zz85 / http://twitter.com/blurspline / http://www.lab4games.net/zz85/blog
 *
 *  A general perpose camera, for setting FOV, Lens Focal Length,
 *      and switching between perspective and orthographic views easily.
 *      Use this only if you do not wish to manage
 *      both a Orthographic and Perspective Camera
 *
 */


THREE.CombinedCamera = function ( width, height, fov, near, far, orthoNear, orthoFar ) {

    THREE.Camera.call( this );

    this.fov = fov;

    this.left = -width / 2;
    this.right = width / 2
    this.top = height / 2;
    this.bottom = -height / 2;

    // We could also handle the projectionMatrix internally, but just wanted to test nested camera objects

    this.cameraO = new THREE.OrthographicCamera( width / - 2, width / 2, height / 2, height / - 2,  orthoNear, orthoFar );
    this.cameraP = new THREE.PerspectiveCamera( fov, width / height, near, far );

    this.zoom = 1;

    this.toPerspective();

    var aspect = width/height;

};

THREE.CombinedCamera.prototype = Object.create( THREE.Camera.prototype );

THREE.CombinedCamera.prototype.toPerspective = function () {

    // Switches to the Perspective Camera

    this.near = this.cameraP.near;
    this.far = this.cameraP.far;

    this.cameraP.fov =  this.fov / this.zoom ;

    this.cameraP.updateProjectionMatrix();

    this.projectionMatrix = this.cameraP.projectionMatrix;

    this.inPerspectiveMode = true;
    this.inOrthographicMode = false;

};

THREE.CombinedCamera.prototype.toOrthographic = function () {

    // Switches to the Orthographic camera estimating viewport from Perspective

    var fov = this.fov;
    var aspect = this.cameraP.aspect;
    var near = this.cameraP.near;
    var far = this.cameraP.far;

    // The size that we set is the mid plane of the viewing frustum

    var hyperfocus = ( near + far ) / 2;

    var halfHeight = Math.tan( fov / 2 ) * hyperfocus;
    var planeHeight = 2 * halfHeight;
    var planeWidth = planeHeight * aspect;
    var halfWidth = planeWidth / 2;

    halfHeight /= this.zoom;
    halfWidth /= this.zoom;

    this.cameraO.left = -halfWidth;
    this.cameraO.right = halfWidth;
    this.cameraO.top = halfHeight;
    this.cameraO.bottom = -halfHeight;

    // this.cameraO.left = -farHalfWidth;
    // this.cameraO.right = farHalfWidth;
    // this.cameraO.top = farHalfHeight;
    // this.cameraO.bottom = -farHalfHeight;

    // this.cameraO.left = this.left / this.zoom;
    // this.cameraO.right = this.right / this.zoom;
    // this.cameraO.top = this.top / this.zoom;
    // this.cameraO.bottom = this.bottom / this.zoom;

    this.cameraO.updateProjectionMatrix();

    this.near = this.cameraO.near;
    this.far = this.cameraO.far;
    this.projectionMatrix = this.cameraO.projectionMatrix;

    this.inPerspectiveMode = false;
    this.inOrthographicMode = true;

};


THREE.CombinedCamera.prototype.setSize = function( width, height ) {

    this.cameraP.aspect = width / height;
    this.left = -width / 2;
    this.right = width / 2
    this.top = height / 2;
    this.bottom = -height / 2;

};


THREE.CombinedCamera.prototype.setFov = function( fov ) {

    this.fov = fov;

    if ( this.inPerspectiveMode ) {

        this.toPerspective();

    } else {

        this.toOrthographic();

    }

};

// For mantaining similar API with PerspectiveCamera

THREE.CombinedCamera.prototype.updateProjectionMatrix = function() {

    if ( this.inPerspectiveMode ) {

        this.toPerspective();

    } else {

        this.toPerspective();
        this.toOrthographic();

    }

};

/*
* Uses Focal Length (in mm) to estimate and set FOV
* 35mm (fullframe) camera is used if frame size is not specified;
* Formula based on http://www.bobatkins.com/photography/technical/field_of_view.html
*/
THREE.CombinedCamera.prototype.setLens = function ( focalLength, frameHeight ) {

    if ( frameHeight === undefined ) frameHeight = 24;

    var fov = 2 * THREE.Math.radToDeg( Math.atan( frameHeight / ( focalLength * 2 ) ) );

    this.setFov( fov );

    return fov;
};


THREE.CombinedCamera.prototype.setZoom = function( zoom ) {

    this.zoom = zoom;

    if ( this.inPerspectiveMode ) {

        this.toPerspective();

    } else {

        this.toOrthographic();

    }

};

THREE.CombinedCamera.prototype.toFrontView = function() {

    this.rotation.x = 0;
    this.rotation.y = 0;
    this.rotation.z = 0;

    // should we be modifing the matrix instead?

    this.rotationAutoUpdate = false;

};

THREE.CombinedCamera.prototype.toBackView = function() {

    this.rotation.x = 0;
    this.rotation.y = Math.PI;
    this.rotation.z = 0;
    this.rotationAutoUpdate = false;

};

THREE.CombinedCamera.prototype.toLeftView = function() {

    this.rotation.x = 0;
    this.rotation.y = - Math.PI / 2;
    this.rotation.z = 0;
    this.rotationAutoUpdate = false;

};

THREE.CombinedCamera.prototype.toRightView = function() {

    this.rotation.x = 0;
    this.rotation.y = Math.PI / 2;
    this.rotation.z = 0;
    this.rotationAutoUpdate = false;

};

THREE.CombinedCamera.prototype.toTopView = function() {

    this.rotation.x = - Math.PI / 2;
    this.rotation.y = 0;
    this.rotation.z = 0;
    this.rotationAutoUpdate = false;

};

THREE.CombinedCamera.prototype.toBottomView = function() {

    this.rotation.x = Math.PI / 2;
    this.rotation.y = 0;
    this.rotation.z = 0;
    this.rotationAutoUpdate = false;

};