File: //var/www/aspa/three/cameras/PerspectiveCamera.js
import { Camera } from './Camera.js';
import * as MathUtils from '../math/MathUtils.js';
import { Vector2 } from '../math/Vector2.js';
import { Vector3 } from '../math/Vector3.js';
const _v3 = /*@__PURE__*/ new Vector3();
const _minTarget = /*@__PURE__*/ new Vector2();
const _maxTarget = /*@__PURE__*/ new Vector2();
class PerspectiveCamera extends Camera {
	constructor( fov = 50, aspect = 1, near = 0.1, far = 2000 ) {
		super();
		this.isPerspectiveCamera = true;
		this.type = 'PerspectiveCamera';
		this.fov = fov;
		this.zoom = 1;
		this.near = near;
		this.far = far;
		this.focus = 10;
		this.aspect = aspect;
		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();
	}
	copy( source, recursive ) {
		super.copy( 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( focalLength ) {
		/** see {@link http://www.bobatkins.com/photography/technical/field_of_view.html} */
		const vExtentSlope = 0.5 * this.getFilmHeight() / focalLength;
		this.fov = MathUtils.RAD2DEG * 2 * Math.atan( vExtentSlope );
		this.updateProjectionMatrix();
	}
	/**
	 * Calculates the focal length from the current .fov and .filmGauge.
	 */
	getFocalLength() {
		const vExtentSlope = Math.tan( MathUtils.DEG2RAD * 0.5 * this.fov );
		return 0.5 * this.getFilmHeight() / vExtentSlope;
	}
	getEffectiveFOV() {
		return MathUtils.RAD2DEG * 2 * Math.atan(
			Math.tan( MathUtils.DEG2RAD * 0.5 * this.fov ) / this.zoom );
	}
	getFilmWidth() {
		// film not completely covered in portrait format (aspect < 1)
		return this.filmGauge * Math.min( this.aspect, 1 );
	}
	getFilmHeight() {
		// film not completely covered in landscape format (aspect > 1)
		return this.filmGauge / Math.max( this.aspect, 1 );
	}
	/**
	 * Computes the 2D bounds of the camera's viewable rectangle at a given distance along the viewing direction.
	 * Sets minTarget and maxTarget to the coordinates of the lower-left and upper-right corners of the view rectangle.
	 */
	getViewBounds( distance, minTarget, maxTarget ) {
		_v3.set( - 1, - 1, 0.5 ).applyMatrix4( this.projectionMatrixInverse );
		minTarget.set( _v3.x, _v3.y ).multiplyScalar( - distance / _v3.z );
		_v3.set( 1, 1, 0.5 ).applyMatrix4( this.projectionMatrixInverse );
		maxTarget.set( _v3.x, _v3.y ).multiplyScalar( - distance / _v3.z );
	}
	/**
	 * Computes the width and height of the camera's viewable rectangle at a given distance along the viewing direction.
	 * Copies the result into the target Vector2, where x is width and y is height.
	 */
	getViewSize( distance, target ) {
		this.getViewBounds( distance, _minTarget, _maxTarget );
		return target.subVectors( _maxTarget, _minTarget );
	}
	/**
	 * 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
	 *
	 *   const w = 1920;
	 *   const h = 1080;
	 *   const fullWidth = w * 3;
	 *   const fullHeight = h * 2;
	 *
	 *   --A--
	 *   camera.setViewOffset( fullWidth, fullHeight, w * 0, h * 0, w, h );
	 *   --B--
	 *   camera.setViewOffset( fullWidth, fullHeight, w * 1, h * 0, w, h );
	 *   --C--
	 *   camera.setViewOffset( fullWidth, fullHeight, w * 2, h * 0, w, h );
	 *   --D--
	 *   camera.setViewOffset( fullWidth, fullHeight, w * 0, h * 1, w, h );
	 *   --E--
	 *   camera.setViewOffset( fullWidth, fullHeight, w * 1, h * 1, w, h );
	 *   --F--
	 *   camera.setViewOffset( 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( 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() {
		if ( this.view !== null ) {
			this.view.enabled = false;
		}
		this.updateProjectionMatrix();
	}
	updateProjectionMatrix() {
		const near = this.near;
		let top = near * Math.tan( MathUtils.DEG2RAD * 0.5 * this.fov ) / this.zoom;
		let height = 2 * top;
		let width = this.aspect * height;
		let left = - 0.5 * width;
		const view = this.view;
		if ( this.view !== null && this.view.enabled ) {
			const fullWidth = view.fullWidth,
				fullHeight = view.fullHeight;
			left += view.offsetX * width / fullWidth;
			top -= view.offsetY * height / fullHeight;
			width *= view.width / fullWidth;
			height *= view.height / fullHeight;
		}
		const skew = this.filmOffset;
		if ( skew !== 0 ) left += near * skew / this.getFilmWidth();
		this.projectionMatrix.makePerspective( left, left + width, top, top - height, near, this.far, this.coordinateSystem );
		this.projectionMatrixInverse.copy( this.projectionMatrix ).invert();
	}
	toJSON( meta ) {
		const data = super.toJSON( 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 };