scrawl-canvas
Version:
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
414 lines (309 loc) • 14.3 kB
JavaScript
// # Cog factory
// A factory for generating star shape-based entitys
// #### Imports
import { constructors } from '../core/library.js';
import { addStrings, doCreate, mergeOver, Ωempty } from '../helper/utilities.js';
import { releaseVector, requestVector } from '../untracked-factory/vector.js';
import baseMix from '../mixin/base.js';
import shapeMix from '../mixin/shape-basic.js';
// Shared constants
import { BEZIER, ENTITY, QUADRATIC, ZERO_PATH, ZERO_STR } from '../helper/shared-vars.js';
// Local constants
const PERMITTED_CURVES = ['line', 'quadratic', 'bezier'],
T_COG = 'Cog';
// #### Cog constructor
const Cog = function (items = Ωempty) {
this.shapeInit(items);
return this;
};
// #### Cog prototype
const P = Cog.prototype = doCreate();
P.type = T_COG;
P.lib = ENTITY;
P.isArtefact = true;
P.isAsset = false;
// #### Mixins
baseMix(P);
shapeMix(P);
// #### Cog attributes
const defaultAttributes = {
outerRadius: 0,
innerRadius: 0,
outerControlsDistance: 0,
innerControlsDistance: 0,
outerControlsOffset: 0,
innerControlsOffset: 0,
points: 0,
twist: 0,
curve: BEZIER,
};
P.defs = mergeOver(P.defs, defaultAttributes);
// #### Packet management
// No additional packet functionality required
// #### Clone management
// No additional clone functionality required
// #### Kill management
// No additional kill functionality required
// #### Get, Set, deltaSet
const S = P.setters,
D = P.deltaSetters;
// __outerRadius__, __innerRadius__
S.outerRadius = function (item) {
this.outerRadius = item;
this.updateDirty();
};
D.outerRadius = function (item) {
this.outerRadius = addStrings(this.outerRadius, item);
this.updateDirty();
};
S.innerRadius = function (item) {
this.innerRadius = item;
this.updateDirty();
};
D.innerRadius = function (item) {
this.innerRadius = addStrings(this.innerRadius, item);
this.updateDirty();
};
// __outerControlsDistance__, __innerControlsDistance__
S.outerControlsDistance = function (item) {
this.outerControlsDistance = item;
this.updateDirty();
};
D.outerControlsDistance = function (item) {
this.outerControlsDistance = addStrings(this.outerControlsDistance, item);
this.updateDirty();
};
S.innerControlsDistance = function (item) {
this.innerControlsDistance = item;
this.updateDirty();
};
D.innerControlsDistance = function (item) {
this.innerControlsDistance = addStrings(this.innerControlsDistance, item);
this.updateDirty();
};
// __outerControlsOffset__, __innerControlsOffset__
S.outerControlsOffset = function (item) {
this.outerControlsOffset = item;
this.updateDirty();
};
D.outerControlsOffset = function (item) {
this.outerControlsOffset = addStrings(this.outerControlsOffset, item);
this.updateDirty();
};
S.innerControlsOffset = function (item) {
this.innerControlsOffset = item;
this.updateDirty();
};
D.innerControlsOffset = function (item) {
this.innerControlsOffset = addStrings(this.innerControlsOffset, item);
this.updateDirty();
};
// __points__
S.points = function (item) {
this.points = item;
this.updateDirty();
};
D.points = function (item) {
this.points += item;
this.updateDirty();
};
// __twist__
S.twist = function (item) {
this.twist = item;
this.updateDirty();
};
D.twist = function (item) {
this.twist += item;
this.updateDirty();
};
// __useBezierCurve__
S.curve = function (item) {
if (item && PERMITTED_CURVES.includes(item)) this.curve = item;
else this.curve = BEZIER;
this.updateDirty();
};
// #### Prototype functions
// `cleanSpecies` - internal helper function - called by `prepareStamp`
P.cleanSpecies = function () {
this.dirtySpecies = false;
this.pathDefinition = this.makeCogPath();
};
// `makeCogPath` - internal helper function - called by `cleanSpecies`
P.makeCogPath = function () {
const { points, twist, curve } = this;
let { outerRadius, innerRadius, outerControlsDistance, innerControlsDistance, outerControlsOffset, innerControlsOffset } = this;
const turn = 360 / points;
let currentPointX, currentPointY, deltaX, deltaY, i,
myPath = ZERO_STR;
if (outerRadius.substring || innerRadius.substring || outerControlsDistance.substring || innerControlsDistance.substring || outerControlsOffset.substring || innerControlsOffset.substring) {
const host = this.getHost();
if (host) {
const [hW] = host.currentDimensions;
outerRadius = (outerRadius.substring) ? (parseFloat(outerRadius) / 100) * hW : outerRadius;
innerRadius = (innerRadius.substring) ? (parseFloat(innerRadius) / 100) * hW : innerRadius;
outerControlsDistance = (outerControlsDistance.substring) ? (parseFloat(outerControlsDistance) / 100) * hW : outerControlsDistance;
innerControlsDistance = (innerControlsDistance.substring) ? (parseFloat(innerControlsDistance) / 100) * hW : innerControlsDistance;
outerControlsOffset = (outerControlsOffset.substring) ? (parseFloat(outerControlsOffset) / 100) * hW : outerControlsOffset;
innerControlsOffset = (innerControlsOffset.substring) ? (parseFloat(innerControlsOffset) / 100) * hW : innerControlsOffset;
}
}
const outerPoint = requestVector({x: 0, y: -outerRadius}),
innerPoint = requestVector({x: 0, y: -innerRadius}),
outerPointLead = requestVector({x: outerControlsDistance + outerControlsOffset, y: -outerRadius}),
innerPointTrail = requestVector({x: -innerControlsDistance + innerControlsOffset, y: -innerRadius}),
innerPointLead = requestVector({x: innerControlsDistance + innerControlsOffset, y: -innerRadius}),
outerPointTrail = requestVector({x: -outerControlsDistance + outerControlsOffset, y: -outerRadius});
innerPointTrail.rotate(-turn/2);
innerPointTrail.rotate(twist);
innerPoint.rotate(-turn/2);
innerPoint.rotate(twist);
innerPointLead.rotate(-turn/2);
innerPointLead.rotate(twist);
currentPointX = outerPoint.x;
currentPointY = outerPoint.y;
if (curve === BEZIER) {
for (i = 0; i < points; i++) {
deltaX = parseFloat((outerPointLead.x - currentPointX).toFixed(1));
deltaY = parseFloat((outerPointLead.y - currentPointY).toFixed(1));
myPath += `${deltaX},${deltaY} `;
innerPointTrail.rotate(turn);
innerPoint.rotate(turn);
innerPointLead.rotate(turn);
deltaX = parseFloat((innerPointTrail.x - currentPointX).toFixed(1));
deltaY = parseFloat((innerPointTrail.y - currentPointY).toFixed(1));
myPath += `${deltaX},${deltaY} `;
deltaX = parseFloat((innerPoint.x - currentPointX).toFixed(1));
currentPointX += deltaX;
deltaY = parseFloat((innerPoint.y - currentPointY).toFixed(1));
currentPointY += deltaY;
myPath += `${deltaX},${deltaY} `;
deltaX = parseFloat((innerPointLead.x - currentPointX).toFixed(1));
deltaY = parseFloat((innerPointLead.y - currentPointY).toFixed(1));
myPath += `${deltaX},${deltaY} `;
outerPointTrail.rotate(turn);
outerPoint.rotate(turn);
outerPointLead.rotate(turn);
deltaX = parseFloat((outerPointTrail.x - currentPointX).toFixed(1));
deltaY = parseFloat((outerPointTrail.y - currentPointY).toFixed(1));
myPath += `${deltaX},${deltaY} `;
deltaX = parseFloat((outerPoint.x - currentPointX).toFixed(1));
currentPointX += deltaX;
deltaY = parseFloat((outerPoint.y - currentPointY).toFixed(1));
currentPointY += deltaY;
myPath += `${deltaX},${deltaY} `;
}
}
else if (curve === QUADRATIC) {
for (i = 0; i < points; i++) {
deltaX = parseFloat((outerPointLead.x - currentPointX).toFixed(1));
deltaY = parseFloat((outerPointLead.y - currentPointY).toFixed(1));
myPath += `${deltaX},${deltaY} `;
innerPoint.rotate(turn);
innerPointLead.rotate(turn);
deltaX = parseFloat((innerPoint.x - currentPointX).toFixed(1));
currentPointX += deltaX;
deltaY = parseFloat((innerPoint.y - currentPointY).toFixed(1));
currentPointY += deltaY;
myPath += `${deltaX},${deltaY} `;
deltaX = parseFloat((innerPointLead.x - currentPointX).toFixed(1));
deltaY = parseFloat((innerPointLead.y - currentPointY).toFixed(1));
myPath += `${deltaX},${deltaY} `;
outerPoint.rotate(turn);
outerPointLead.rotate(turn);
deltaX = parseFloat((outerPoint.x - currentPointX).toFixed(1));
currentPointX += deltaX;
deltaY = parseFloat((outerPoint.y - currentPointY).toFixed(1));
currentPointY += deltaY;
myPath += `${deltaX},${deltaY} `;
}
}
else {
for (i = 0; i < points; i++) {
deltaX = parseFloat((outerPointLead.x - currentPointX).toFixed(1));
currentPointX += deltaX;
deltaY = parseFloat((outerPointLead.y - currentPointY).toFixed(1));
currentPointY += deltaY;
myPath += `${deltaX},${deltaY} `;
innerPointTrail.rotate(turn);
innerPoint.rotate(turn);
innerPointLead.rotate(turn);
deltaX = parseFloat((innerPointTrail.x - currentPointX).toFixed(1));
currentPointX += deltaX;
deltaY = parseFloat((innerPointTrail.y - currentPointY).toFixed(1));
currentPointY += deltaY;
myPath += `${deltaX},${deltaY} `;
deltaX = parseFloat((innerPoint.x - currentPointX).toFixed(1));
currentPointX += deltaX;
deltaY = parseFloat((innerPoint.y - currentPointY).toFixed(1));
currentPointY += deltaY;
myPath += `${deltaX},${deltaY} `;
deltaX = parseFloat((innerPointLead.x - currentPointX).toFixed(1));
currentPointX += deltaX;
deltaY = parseFloat((innerPointLead.y - currentPointY).toFixed(1));
currentPointY += deltaY;
myPath += `${deltaX},${deltaY} `;
outerPointTrail.rotate(turn);
outerPoint.rotate(turn);
outerPointLead.rotate(turn);
deltaX = parseFloat((outerPointTrail.x - currentPointX).toFixed(1));
currentPointX += deltaX;
deltaY = parseFloat((outerPointTrail.y - currentPointY).toFixed(1));
currentPointY += deltaY;
myPath += `${deltaX},${deltaY} `;
deltaX = parseFloat((outerPoint.x - currentPointX).toFixed(1));
currentPointX += deltaX;
deltaY = parseFloat((outerPoint.y - currentPointY).toFixed(1));
currentPointY += deltaY;
myPath += `${deltaX},${deltaY} `;
}
}
releaseVector(outerPoint, outerPointLead, outerPointTrail, innerPoint, innerPointLead, innerPointTrail);
if (curve === BEZIER) return `${ZERO_PATH}c${myPath}z`;
if (curve === QUADRATIC) return `${ZERO_PATH}q${myPath}z`;
return `${ZERO_PATH}l${myPath}z`;
};
P.calculateLocalPathAdditionalActions = function () {
let scale = this.scale;
if (scale < 0.001) scale = 0.001;
const [x, y] = this.localBox;
this.pathDefinition = this.pathDefinition.replace(ZERO_PATH, `m${-x / scale},${-y / scale}`);
this.pathCalculatedOnce = false;
// ALWAYS, when invoking `calculateLocalPath` from `calculateLocalPathAdditionalActions`, include the second argument, set to `true`! Failure to do this leads to an infinite loop which will make your machine weep.
// + We need to recalculate the local path to take into account the offset required to put the Rectangle entity's start coordinates at the top-left of the local box, and to recalculate the data used by other artefacts to place themselves on, or move along, its path.
this.calculateLocalPath(this.pathDefinition, true);
};
// #### Factories
// ##### makeCog
// Accepts argument with attributes:
// + __outerRadius__ (required) - the _outer_ radius representing the distance between the center of the Shape and the tips of its (acute angle) points.
// + __innerRadius__ (required) - the _inner_ radius representing the distance between the center of the Shape and the obtuse angle at the valley between the tips of its (acute angle) points.
// + ... where these radius values are supplied as %Strings, they are calculated as relative to the canvas/cell ___width___ value.
// + __outerControlsDistance__, __innerControlsDistance__ - a Number value measuring the distance from each point to its leading and trailing control points - use this to create more square pegs (useBezierCurve: false) or a more curved tooth outline
// + __outerControlsOffset__, __innerControlsOffset__ - a Number value which can be used to offset the control points so that the trailing control point is more distant than the leading control point (or vice versa)
// + __points__ (required) - a positive integer Number representing the number of points the star will have.
// + __twist__ - a float Number representing the degrees by which the star's second radius will be rotated out of line from its first radius; the default value `0` will produce a star with all of its sides of equal length and the star's valleys falling midway between its connecting points.
// + __curve__ - String: one of 'bezier' (default); 'quadratic'; or 'line' - when this flag is set, the entity will be built using the appropriate curve.
// + Note that the use of _inner_ and _outer_ above is purely descriptive: `innerRadius` can be larger than `outerRadius`
//
// ```
// scrawl.makeCog({
//
// name: 'smooth-cog',
// startX: 20,
// startY: 1980,
// outerRadius: 80,
// innerRadius: 60,
// outerControlsDistance: 10,
// innerControlsDistance: 6,
// points: 12,
// fillStyle: 'coral',
// lineWidth: 2,
// method: 'fillAndDraw',
// });
// ```
export const makeCog = function (items) {
if (!items) return false;
items.species = 'cog';
return new Cog(items);
};
constructors.Cog = Cog;