fireball/lib/cameras/PerspectiveCamera.js
2018-12-25 17:29:22 +03:30

245 lines
5.6 KiB
JavaScript
Executable File

import { Camera } from './Camera.js';
import { Object3D } from '../core/Object3D.js';
import { _Math } from '../math/Math.js';
/**
* @author mrdoob / http://mrdoob.com/
* @author greggman / http://games.greggman.com/
* @author zz85 / http://www.lab4games.net/zz85/blog
* @author tschw
*/
function PerspectiveCamera( fov, aspect, near, far ) {
Camera.call( this );
this.type = 'PerspectiveCamera';
this.fov = fov !== undefined ? fov : 50;
this.zoom = 1;
this.near = near !== undefined ? near : 0.1;
this.far = far !== undefined ? far : 2000;
this.focus = 10;
this.aspect = aspect !== undefined ? aspect : 1;
this.view = null;
this.filmGauge = 35; // width of the film (default in millimeters)
this.filmOffset = 0; // horizontal film offset (same unit as gauge)
this.updateProjectionMatrix();
}
PerspectiveCamera.prototype = Object.assign( Object.create( Camera.prototype ), {
constructor: PerspectiveCamera,
isPerspectiveCamera: true,
copy: function ( source, recursive ) {
Camera.prototype.copy.call( this, source, recursive );
this.fov = source.fov;
this.zoom = source.zoom;
this.near = source.near;
this.far = source.far;
this.focus = source.focus;
this.aspect = source.aspect;
this.view = source.view === null ? null : Object.assign( {}, source.view );
this.filmGauge = source.filmGauge;
this.filmOffset = source.filmOffset;
return this;
},
/**
* Sets the FOV by focal length in respect to the current .filmGauge.
*
* The default film gauge is 35, so that the focal length can be specified for
* a 35mm (full frame) camera.
*
* Values for focal length and film gauge must have the same unit.
*/
setFocalLength: function ( focalLength ) {
// see http://www.bobatkins.com/photography/technical/field_of_view.html
var vExtentSlope = 0.5 * this.getFilmHeight() / focalLength;
this.fov = _Math.RAD2DEG * 2 * Math.atan( vExtentSlope );
this.updateProjectionMatrix();
},
/**
* Calculates the focal length from the current .fov and .filmGauge.
*/
getFocalLength: function () {
var vExtentSlope = Math.tan( _Math.DEG2RAD * 0.5 * this.fov );
return 0.5 * this.getFilmHeight() / vExtentSlope;
},
getEffectiveFOV: function () {
return _Math.RAD2DEG * 2 * Math.atan(
Math.tan( _Math.DEG2RAD * 0.5 * this.fov ) / this.zoom );
},
getFilmWidth: function () {
// film not completely covered in portrait format (aspect < 1)
return this.filmGauge * Math.min( this.aspect, 1 );
},
getFilmHeight: function () {
// film not completely covered in landscape format (aspect > 1)
return this.filmGauge / Math.max( this.aspect, 1 );
},
/**
* Sets an offset in a larger frustum. This is useful for multi-window or
* multi-monitor/multi-machine setups.
*
* For example, if you have 3x2 monitors and each monitor is 1920x1080 and
* the monitors are in grid like this
*
* +---+---+---+
* | A | B | C |
* +---+---+---+
* | D | E | F |
* +---+---+---+
*
* then for each monitor you would call it like this
*
* var w = 1920;
* var h = 1080;
* var fullWidth = w * 3;
* var fullHeight = h * 2;
*
* --A--
* camera.setOffset( fullWidth, fullHeight, w * 0, h * 0, w, h );
* --B--
* camera.setOffset( fullWidth, fullHeight, w * 1, h * 0, w, h );
* --C--
* camera.setOffset( fullWidth, fullHeight, w * 2, h * 0, w, h );
* --D--
* camera.setOffset( fullWidth, fullHeight, w * 0, h * 1, w, h );
* --E--
* camera.setOffset( fullWidth, fullHeight, w * 1, h * 1, w, h );
* --F--
* camera.setOffset( fullWidth, fullHeight, w * 2, h * 1, w, h );
*
* Note there is no reason monitors have to be the same size or in a grid.
*/
setViewOffset: function ( fullWidth, fullHeight, x, y, width, height ) {
this.aspect = fullWidth / fullHeight;
if ( this.view === null ) {
this.view = {
enabled: true,
fullWidth: 1,
fullHeight: 1,
offsetX: 0,
offsetY: 0,
width: 1,
height: 1
};
}
this.view.enabled = true;
this.view.fullWidth = fullWidth;
this.view.fullHeight = fullHeight;
this.view.offsetX = x;
this.view.offsetY = y;
this.view.width = width;
this.view.height = height;
this.updateProjectionMatrix();
},
clearViewOffset: function () {
if ( this.view !== null ) {
this.view.enabled = false;
}
this.updateProjectionMatrix();
},
updateProjectionMatrix: function () {
var near = this.near,
top = near * Math.tan( _Math.DEG2RAD * 0.5 * this.fov ) / this.zoom,
height = 2 * top,
width = this.aspect * height,
left = - 0.5 * width,
view = this.view;
if ( this.view !== null && this.view.enabled ) {
var fullWidth = view.fullWidth,
fullHeight = view.fullHeight;
left += view.offsetX * width / fullWidth;
top -= view.offsetY * height / fullHeight;
width *= view.width / fullWidth;
height *= view.height / fullHeight;
}
var skew = this.filmOffset;
if ( skew !== 0 ) left += near * skew / this.getFilmWidth();
this.projectionMatrix.makePerspective( left, left + width, top, top - height, near, this.far );
this.projectionMatrixInverse.getInverse( this.projectionMatrix );
},
toJSON: function ( meta ) {
var data = Object3D.prototype.toJSON.call( this, meta );
data.object.fov = this.fov;
data.object.zoom = this.zoom;
data.object.near = this.near;
data.object.far = this.far;
data.object.focus = this.focus;
data.object.aspect = this.aspect;
if ( this.view !== null ) data.object.view = Object.assign( {}, this.view );
data.object.filmGauge = this.filmGauge;
data.object.filmOffset = this.filmOffset;
return data;
}
} );
export { PerspectiveCamera };