scrawl-canvas/source/factory/quadratic.js

Responsive, interactive and more accessible HTML5 canvas elements. Scrawl-canvas is a JavaScript library designed to make using the HTML5 canvas element easier, and more fun

// # Quadratic factory
// A factory for generating quadratic curve shape-based entitys


// #### Imports
import { constructors } from '../core/library.js';

import { addStrings, doCreate, mergeOver, pushUnique, Ωempty } from '../helper/utilities.js';

import { makeCoordinate } from '../untracked-factory/coordinate.js';

import baseMix from '../mixin/base.js';
import shapeMix from '../mixin/shape-basic.js';
import curveMix from '../mixin/shape-curve.js';

// Shared constants
import { CONTROL, ENTITY, PATH, QUADRATIC, T_QUADRATIC, ZERO_PATH, ZERO_STR } from '../helper/shared-vars.js';

// Local constants
const CONTROL_PARTICLE = 'controlParticle',
    CONTROL_PATH = 'controlPath',
    CONTROL_PIVOT = 'controlPivot';


// #### Quadratic constructor
const Quadratic = function (items = Ωempty) {

    this.control = makeCoordinate();
    this.currentControl = makeCoordinate();
    this.controlLockTo = 'coord';

    this.curveInit(items);
    this.shapeInit(items);

    this.dirtyControl = true;

    return this;
};


// #### Quadratic prototype
const P = Quadratic.prototype = doCreate();
P.type = T_QUADRATIC;
P.lib = ENTITY;
P.isArtefact = true;
P.isAsset = false;


// #### Mixins
baseMix(P);
shapeMix(P);
curveMix(P);


// #### Quadratic attributes
const defaultAttributes = {

// The __control__ coordinate ('pin') defines the quadratic curve's control point.
// + Similar to the `start` coordinate, the `control` coordinate can be updated using the pseudo-attributes __controlX__ and __controlY__.
    control: null,

// __controlPivot__, __controlPivotCorner__, __addControlPivotHandle__, __addControlPivotOffset__
// + Like the `start` coordinate, the `control` coordinate can be __pivoted__ to another artefact. These attributes are used in the same way as the `pivot`, 'pivotCorner', `addPivotHandle` and `addPivotOffset` attributes.
    controlPivot: ZERO_STR,
    controlPivotCorner: ZERO_STR,
    controlPivotIndex: -1,
    addControlPivotHandle: false,
    addControlPivotOffset: false,

// __controlPath__, __controlPathPosition__, __addControlPathHandle__, __addControlPathOffset__
// + Like the `start` coordinate, the `control` coordinate can be __pathed__ to another artefact. These attributes are used in the same way as the `path`, 'pathPosition', `addPathHandle` and `addPathOffset` attributes.
    controlPath: ZERO_STR,
    controlPathPosition: 0,
    addControlPathHandle: false,
    addControlPathOffset: true,

// __controlParticle__ - attribute to store any particle the artefact mey be using for its position reference
    controlParticle: ZERO_STR,

// __controlLockTo__
// + Like the `start` coordinate, the `control` coordinate can swap between using absolute and relative positioning by setting this attribute. Accepted values are: `coord` (default, for absolute positioning), `pivot`, `path`, `mouse`.
// + The control coordinate does not support 'mimic' relative positioning.
// + The control lock does not support setting the `x` and `y` coordinates separately - its value is a string argument, not an `[x, y]` array!
    controlLockTo: ZERO_STR,
};
P.defs = mergeOver(P.defs, defaultAttributes);


// #### Packet management
P.packetCoordinates = pushUnique(P.packetCoordinates, ['control']);
P.packetObjects = pushUnique(P.packetObjects, ['controlPivot', 'controlPath']);


// #### Clone management
// No additional clone functionality required


// #### Kill management
// No additional kill functionality required


// #### Get, Set, deltaSet
const G = P.getters,
    S = P.setters,
    D = P.deltaSetters;

// __controlPivot__
S.controlPivot = function (item) {

    this.setControlHelper(item, CONTROL_PIVOT, CONTROL);
    this.updateDirty();
    this.dirtyControl = true;
};

// __controlParticle__
S.controlParticle = function (item) {

    this.setControlHelper(item, CONTROL_PARTICLE, CONTROL);
    this.updateDirty();
    this.dirtyControl = true;
};

// __controlPath__
S.controlPath = function (item) {

    this.setControlHelper(item, CONTROL_PATH, CONTROL);
    this.updateDirty();
    this.dirtyControl = true;
    this.currentControlPathData = false;
};

// __controlPathPosition__
S.controlPathPosition = function (item) {

    this.controlPathPosition = item;
    this.dirtyControl = true;
    this.currentControlPathData = false;
    this.dirtyFilterIdentifier = true;
};
D.controlPathPosition = function (item) {

    this.controlPathPosition += item;
    this.dirtyControl = true;
    this.currentControlPathData = false;
    this.dirtyFilterIdentifier = true;
};

// __control__
// + pseudo-attributes __controlX__, __controlY__
G.controlPositionX = function () {

    return this.currentControl[0];
};
G.controlPositionY = function () {

    return this.currentControl[1];
};
G.controlPosition = function () {

    return [].concat(this.currentControl);
};

S.controlX = function (coord) {

    if (coord != null) {

        this.control[0] = coord;
        this.updateDirty();
        this.dirtyControl = true;
        this.currentControlPathData = false;
    }
};
S.controlY = function (coord) {

    if (coord != null) {

        this.control[1] = coord;
        this.updateDirty();
        this.dirtyControl = true;
        this.currentControlPathData = false;
    }
};
S.control = function (x, y) {

    this.setCoordinateHelper(CONTROL, x, y);
    this.updateDirty();
    this.dirtyControl = true;
    this.currentControlPathData = false;
};
D.controlX = function (coord) {

    const c = this.control;
    c[0] = addStrings(c[0], coord);
    this.updateDirty();
    this.dirtyControl = true;
    this.currentControlPathData = false;
};
D.controlY = function (coord) {

    const c = this.control;
    c[1] = addStrings(c[1], coord);
    this.updateDirty();
    this.dirtyControl = true;
    this.currentControlPathData = false;
};
D.control = function (x, y) {

    this.setDeltaCoordinateHelper(CONTROL, x, y);
    this.updateDirty();
    this.dirtyControl = true;
    this.currentControlPathData = false;
};

// __controlLockTo__
S.controlLockTo = function (item) {

    this.controlLockTo = item;
    this.updateDirty();
    this.dirtyControlLock = true;
    this.currentControlPathData = false;
};


// #### Prototype functions

// `cleanSpecies` - internal helper function - called by `prepareStamp`
P.cleanSpecies = function () {

    this.dirtySpecies = false;
    this.pathDefinition = this.makeQuadraticPath();
};

// `makeQuadraticPath` - internal helper function - called by `cleanSpecies`
P.makeQuadraticPath = function () {

    const [startX, startY] = this.currentStampPosition;
    const [controlX, controlY] = this.currentControl;
    const [endX, endY] = this.currentEnd;

    return `${ZERO_PATH}q${(controlX - startX).toFixed(2)},${(controlY - startY).toFixed(2)} ${(endX - startX).toFixed(2)},${(endY - startY).toFixed(2)}`;
};

// `cleanDimensions` - internal helper function called by `prepareStamp`
// + Dimensional data has no meaning in the context of Shape entitys (beyond positioning handle Coordinates): width and height are emergent properties that cannot be set on the entity.
P.cleanDimensions = function () {

    this.dirtyDimensions = false;
    this.dirtyHandle = true;
    this.dirtyOffset = true;

    this.dirtyStart = true;
    this.dirtyControl = true;
    this.dirtyEnd = true;

    this.dirtyFilterIdentifier = true;
};

P.preparePinsForStamp = function () {

    const dirtyPins = this.dirtyPins,
        ePivot = this.endPivot,
        ePath = this.endPath,
        cPivot = this.controlPivot,
        cPath = this.controlPath;

    for (let i = 0, iz = dirtyPins.length, name; i < iz; i++) {

        name = dirtyPins[i];

        if ((cPivot && cPivot.name === name) || (cPath && cPath.name === name)) {

            this.dirtyControl = true;
            if (this.controlLockTo.includes(PATH)) this.currentControlPathData = false;
        }

        if ((ePivot && ePivot.name === name) || (ePath && ePath.name === name)) {

            this.dirtyEnd = true;
            if (this.endLockTo.includes(PATH)) this.currentEndPathData = false;
        }
    }
    dirtyPins.length = 0;
};

// #### Factories

// ##### makeQuadratic
// Accepts argument with attributes:
// + __start__ (___startX___, ___startY___) Coordinate, or __pivot__/__mimic__/__path__ reference artefact (required)
// + __control__ (___controlX___, ___controlY___) Coordinate, or __controlPivot__/__controlPath__ reference artefact (required)
// + __end__ (___endX___, ___endY___) Coordinate, or __endPivot__/__endPath__ reference artefact (required)
// + If using reference artefacts, may also need to set the __lockTo__ (___lockXTo___, ___lockYTo___), __controlLockTo__ and __endLockTo__ lock attributes
// + additional reference-linked attributes for the `control` coordinate: __controlPivotCorner__, __addControlPivotHandle__, __addControlPivotOffset__, __controlPathPosition__, __addControlPathHandle__, __addControlPathOffset__
// + additional reference-linked attributes for the `end` coordinate: __endPivotCorner__, __addEndPivotHandle__, __addEndPivotOffset__, __endPathPosition__, __addEndPathHandle__, __addEndPathOffset__
//
// ```
// scrawl.makeQuadratic({
//
//     name: 'my-quadratic',
//
//     startX: '5%',
//     startY: '26.5%',
//
//     controlX: '50%',
//     controlY: '18%',
//
//     endX: '95%',
//     endY: '26.5%',
//
//     handleY: 'center',
//
//     lineWidth: 3,
//     lineCap: 'round',
//     strokeStyle: 'darkseagreen',
//
//     method: 'draw',
// });
// ```
export const makeQuadratic = function (items = Ωempty) {

    if (!items) return false;
    items.species = QUADRATIC;
    return new Quadratic(items);
};

constructors.Quadratic = Quadratic;