File : core/mapIcon/TranslationRotationFinder.js

/*

Copyright - 2017 2023 - wwwouaiebe - Contact: https://www.ouaie.be/

This  program is free software;

you can redistribute it and/or modify it under the terms of the

GNU General Public License as published by the Free Software Foundation;

either version 3 of the License, or any later version.

This program is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

GNU General Public License for more details.

You should have received a copy of the GNU General Public License

along with this program; if not, write to the Free Software

Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

*/

/*

Changes:

    - v4.0.0:

        - created from v3.6.0

Doc reviewed 202208

 */

import theConfig from '../../data/Config.js';

import theGeometry from '../../core/lib/Geometry.js';

import theSphericalTrigonometry from '../../core/lib/SphericalTrigonometry.js';

import { ICON_DIMENSIONS, ZERO, ONE, TWO, DEGREES, ICON_POSITION } from '../../main/Constants.js';

/* ------------------------------------------------------------------------------------------------------------------------- */

/**

Search:

- the translation needed to have the icon point in the middle of the icon

- the rotation needed to have the entry point at the bottom of the icon

- the direction to follow

- adapt the icon if icon is on the start or the end point

*/

/* ------------------------------------------------------------------------------------------------------------------------- */

class TranslationRotationFinder {

    /**

    A reference to the computeData object of the MapIconFromOsmFactory

    @type {ComputeDataForMapIcon}

    */

    #computeData;

    /**

    A reference to the noteData Object of the MapIconFromOsmFactory

    @type {NoteDataForMapIcon}

    */

    #noteData;

    /**

    A reference to the itineraryPoint used to compute the rotation

    @type {ItineraryPoint}

    */

    #rotationItineraryPoint;

    /**

    A reference to the itineraryPoint used to compute the direction

    @type {ItineraryPoint}

    */

    #directionItineraryPoint;

    /**

    The coordinates in pixel of the icon point

    @type {Array.<Number>}

    */

    #iconPoint;

    /**

    This method compute the translation needed to have the itinerary point in the middle of the svg

    */

    #computeTranslation ( ) {

        this.#computeData.translation = theGeometry.subtrackPoints (

            [ ICON_DIMENSIONS.svgViewboxDim / TWO, ICON_DIMENSIONS.svgViewboxDim / TWO ],

            theGeometry.project ( this.#noteData.latLng, theConfig.note.svgIcon.zoom )

        );

    }

    /**

    Searching a point at least at 10 m ( theConfig.note.svgIcon.angleDistance ) from the icon point for rotation

    */

    #findRotationPoint ( ) {

        this.#rotationItineraryPoint = this.#computeData.route.itinerary.itineraryPoints.previous (

            this.#computeData.nearestItineraryPointObjId,

            itineraryPoint => theSphericalTrigonometry.pointsDistance ( itineraryPoint.latLng, this.#noteData.latLng )

                >

                theConfig.note.svgIcon.angleDistance

        )

        ||

        this.#computeData.route.itinerary.itineraryPoints.first;

    }

    /**

    Searching a point at least at 10 m ( theConfig.note.svgIcon.angleDistance ) from the icon point for direction

    */

    #findDirectionPoint ( ) {

        this.#directionItineraryPoint = this.#computeData.route.itinerary.itineraryPoints.next (

            this.#computeData.nearestItineraryPointObjId,

            itineraryPoint => theSphericalTrigonometry.pointsDistance ( itineraryPoint.latLng, this.#noteData.latLng )

                >

                theConfig.note.svgIcon.angleDistance

        )

        ||

        this.#computeData.route.itinerary.itineraryPoints.last;

    }

    /**

    Transform the latLng of the icon ro pixel coordinates relative to the map origin

    */

    #computeIconPoint ( ) {

        this.#iconPoint = theGeometry.addPoints (

            theGeometry.project ( this.#noteData.latLng, theConfig.note.svgIcon.zoom ),

            this.#computeData.translation

        );

    }

    /**

    Computing rotation... if possible

    */

    #findRotation ( ) {

        if (

            this.#computeData.nearestItineraryPointObjId

            !==

            this.#computeData.route.itinerary.itineraryPoints.first.objId

        ) {

            const rotationPoint = theGeometry.addPoints (

                theGeometry.project ( this.#rotationItineraryPoint.latLng, theConfig.note.svgIcon.zoom ),

                this.#computeData.translation

            );

            this.#computeData.rotation =

                Math.atan (

                    ( this.#iconPoint [ ONE ] - rotationPoint [ ONE ] )

                    /

                    ( rotationPoint [ ZERO ] - this.#iconPoint [ ZERO ] )

                )

                *

                DEGREES.d180 / Math.PI;

            if ( ZERO > this.#computeData.rotation ) {

                this.#computeData.rotation += DEGREES.d360;

            }

            this.#computeData.rotation -= DEGREES.d270;

            // point 0,0 of the svg is the UPPER left corner

            if ( ZERO > rotationPoint [ ZERO ] - this.#iconPoint [ ZERO ] ) {

                this.#computeData.rotation += DEGREES.d180;

            }

        }

    }

    /**

    Computing direction ... if possible

    */

    #findDirection ( ) {

        if (

            this.#computeData.nearestItineraryPointObjId

            !==

            this.#computeData.route.itinerary.itineraryPoints.last.objId

        ) {

            const directionPoint = theGeometry.addPoints (

                theGeometry.project ( this.#directionItineraryPoint.latLng, theConfig.note.svgIcon.zoom ),

                this.#computeData.translation

            );

            this.#computeData.direction = Math.atan (

                ( this.#iconPoint [ ONE ] - directionPoint [ ONE ] )

                /

                ( directionPoint [ ZERO ] - this.#iconPoint [ ZERO ] )

            )

                *

                DEGREES.d180 / Math.PI;

            // point 0,0 of the svg is the UPPER left corner

            if ( ZERO > directionPoint [ ZERO ] - this.#iconPoint [ ZERO ] ) {

                this.#computeData.direction += DEGREES.d180;

            }

            this.#computeData.direction -= this.#computeData.rotation;

            // setting direction between 0 and 360

            while ( DEGREES.d0 > this.#computeData.direction ) {

                this.#computeData.direction += DEGREES.d360;

            }

            while ( DEGREES.d360 < this.#computeData.direction ) {

                this.#computeData.direction -= DEGREES.d360;

            }

        }

    }

    /**

    Search if the icon is at the start or the end of the route and adapt data

    */

    #findPositionOnRoute ( ) {

        if (

            this.#computeData.nearestItineraryPointObjId

            ===

            this.#computeData.route.itinerary.itineraryPoints.first.objId

        ) {

            this.#computeData.rotation = -this.#computeData.direction - DEGREES.d90;

            this.#computeData.direction = null;

            this.#computeData.positionOnRoute = ICON_POSITION.atStart;

        }

        if (

            this.#noteData.latLng [ ZERO ] === this.#computeData.route.itinerary.itineraryPoints.last.lat

            &&

            this.#noteData.latLng [ ONE ] === this.#computeData.route.itinerary.itineraryPoints.last.lng

        ) {

            // using lat & lng because last point is sometime duplicated

            this.#computeData.direction = null;

            this.#computeData.positionOnRoute = ICON_POSITION.atEnd;

        }

    }

    /**

    The constructor

    */

    constructor ( ) {

        Object.freeze ( this );

    }

    /**

    this method compute the rotation needed to have the SVG oriented on the itinerary

    and compute also the direction to take after the icon

    @param {ComputeDataForMapIcon} computeData The object with the data needed for the computations

    @param {NoteDataForMapIcon} noteData The object with the nota data

    */

    findData ( computeData, noteData ) {

        this.#computeData = computeData;

        this.#noteData = noteData;

        this.#computeTranslation ( );

        this.#findRotationPoint ( );

        this.#findDirectionPoint ( );

        this.#computeIconPoint ( );

        this.#findRotation ( );

        this.#findDirection ( );

        this.#findPositionOnRoute ( );

    }

}

export default TranslationRotationFinder;

/* --- End of file --------------------------------------------------------------------------------------------------------- */