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scrawl-canvas

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// # Cog factory // A factory for generating star shape-based entitys // // Path-defined entitys represent a diverse range of shapes rendered onto a DOM &lt;canvas> element using the Canvas API's [Path2D interface](https://developer.mozilla.org/en-US/docs/Web/API/Path2D). They use the [shapeBasic](../mixin/shapeBasic.html) and [shapePathCalculation](../mixin/shapePathCalculation.html) (some also use [shapeCurve](../mixin/shapeCurve.html)) mixins to define much of their functionality. // // All path-defined entitys can be positioned, cloned, filtered etc: // + Positioning functionality for the entity is supplied by the __position__ mixin, while rendering functionality comes from the __entity__ mixin. // + Dimensions, however, have little meaning for path-defined entitys - their width and height are determined by their SVG path data Strings; use `scale` instead. // + Path-defined entitys can use CSS color Strings for their fillStyle and strokeStyle values, alongside __Gradient__, __RadialGradient__, __Color__ and __Pattern__ objects. // + They will also accept __Filter__ objects. // + They can use __Anchor__ objects for user navigation. // + They can be rendered to the canvas by including them in a __Cell__ object's __Group__. // + They can be __animated__ directly, or using delta animation, or act as the target for __Tween__ animations. // + Path-defined entitys can be cloned, and killed. // #### Using path-defined entitys as Scrawl-canvas paths // A path is a track - straight, or curved, or as complex as required - placed across a container which artefacts can use as a source of their positioning data. We can animate an artifact to move along the path: // + To enable a path-defined entity to be used as a path by other artefacts, set its `useAsPath` flag to `true`. // + The artefact can then set its `path` attribute to the path-defined entity's name-String (or the entity itself), and set its `lockTo` Array values to `"path"`. // + We position the artefact by setting its `pathPosition` attribute to a float Number value between `0.0 - 1.0`, with `0` being the start of the path, and `1` being its end. // + Path-defined entitys can use other path-defined entitys as a path. // + Phrase entitys can use a path to position their text block; they can also use a path to position each letter individually along the path. // + Artefacts (and letters) can be rotated so that they match the rotation at that point along the path - ___tangential rotation___ by setting their `addPathRotation` flag to `true`. // + Animate an artefact along the path by either using the artefact's `delta` object, or triggering a Tween to perform the movement. // #### Demos: // + [Canvas-011](../../demo/canvas-011.html) - Shape entity (make, clone, method); drag and drop shape entitys // + [Canvas-012](../../demo/canvas-012.html) - Shape entity position; shape entity as a path for other artefacts to follow // + [Canvas-013](../../demo/canvas-013.html) - Path-defined entitys: oval, rectangle, line, quadratic, bezier, tetragon, polygon, star, spiral, cog // + [Canvas-014](../../demo/canvas-014.html) - Line, quadratic and bezier entitys - control lock alternatives // + [Canvas-018](../../demo/canvas-018.html) - Phrase entity - text along a path // + [Canvas-024](../../demo/canvas-024.html) - Loom entity functionality // + [Canvas-030](../../demo/canvas-030.html) - Polyline entity functionality // + [Canvas-038](../../demo/canvas-038.html) - Responsive Shape-based entitys // + [DOM-015](../../demo/dom-015.html) - Use stacked DOM artefact corners as pivot points // + [Packets-002](../../demo/packets-002.html) - Scrawl-canvas packets - save and load a range of different entitys // #### Imports import { constructors } from '../core/library.js'; import { mergeOver, Ωempty } from '../core/utilities.js'; import { requestVector, releaseVector } from './vector.js'; import baseMix from '../mixin/base.js'; import shapeMix from '../mixin/shapeBasic.js'; // #### Cog constructor const Cog = function (items = Ωempty) { this.shapeInit(items); return this; }; // #### Cog prototype let P = Cog.prototype = Object.create(Object.prototype); P.type = 'Cog'; P.lib = 'entity'; P.isArtefact = true; P.isAsset = false; // #### Mixins // + [base](../mixin/base.html) // + [shapeBasic](../mixin/shapeBasic.html) P = baseMix(P); P = shapeMix(P); // #### Cog attributes // + Attributes defined in the [base mixin](../mixin/base.html): __name__. // + Attributes defined in the [position mixin](../mixin/position.html): __group, visibility, order, calculateOrder, stampOrder, start, _startX_, _startY_, handle, _handleX_, _handleY_, offset, _offsetX_, _offsetY_, dimensions, _width_, _height_, pivoted, mimicked, lockTo, _lockXTo_, _lockYTo_, scale, roll, noUserInteraction, noPositionDependencies, noCanvasEngineUpdates, noFilters, noPathUpdates, purge, bringToFrontOnDrag__. // + Attributes defined in the [delta mixin](../mixin/delta.html): __delta, noDeltaUpdates__. // + Attributes defined in the [pivot mixin](../mixin/pivot.html): __pivot, pivotCorner, addPivotHandle, addPivotOffset, addPivotRotation__. // + Attributes defined in the [mimic mixin](../mixin/mimic.html): __mimic, useMimicDimensions, useMimicScale, useMimicStart, useMimicHandle, useMimicOffset, useMimicRotation, useMimicFlip, addOwnDimensionsToMimic, addOwnScaleToMimic, addOwnStartToMimic, addOwnHandleToMimic, addOwnOffsetToMimic, addOwnRotationToMimic__. // + Attributes defined in the [path mixin](../mixin/path.html): __path, pathPosition, addPathHandle, addPathOffset, addPathRotation, constantPathSpeed__. // + Attributes defined in the [entity mixin](../mixin/entity.html): __method, pathObject, winding, flipReverse, flipUpend, scaleOutline, lockFillStyleToEntity, lockStrokeStyleToEntity, onEnter, onLeave, onDown, onUp, _fillStyle, strokeStyle, globalAlpha, globalCompositeOperation, lineWidth, lineCap, lineJoin, lineDash, lineDashOffset, miterLimit, shadowOffsetX, shadowOffsetY, shadowBlur, shadowColor, filter___. // + Attributes defined in the [anchor mixin](../mixin/anchor.html): __anchor__. // + Attributes defined in the [filter mixin](../mixin/filter.html): __filters, isStencil__. // + Attributes defined in the [shapeBasic mixin](../mixin/shapeBasic.html): __species, useAsPath, precision, pathDefinition, showBoundingBox, boundingBoxColor, minimumBoundingBoxDimensions, constantPathSpeed__. let 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 let S = P.setters, D = P.deltaSetters; // __outerRadius__, __innerRadius__ S.outerRadius = function (item) { this.outerRadius = item; this.updateDirty(); }; D.outerRadius = function (item) { this.outerRadius += item; this.updateDirty(); }; S.innerRadius = function (item) { this.innerRadius = item; this.updateDirty(); }; D.innerRadius = function (item) { this.innerRadius += item; this.updateDirty(); }; // __outerControlsDistance__, __innerControlsDistance__ S.outerControlsDistance = function (item) { this.outerControlsDistance = item; this.updateDirty(); }; D.outerControlsDistance = function (item) { this.outerControlsDistance += item; this.updateDirty(); }; S.innerControlsDistance = function (item) { this.innerControlsDistance = item; this.updateDirty(); }; D.innerControlsDistance = function (item) { this.innerControlsDistance += item; this.updateDirty(); }; // __outerControlsOffset__, __innerControlsOffset__ S.outerControlsOffset = function (item) { this.outerControlsOffset = item; this.updateDirty(); }; D.outerControlsOffset = function (item) { this.outerControlsOffset += item; this.updateDirty(); }; S.innerControlsOffset = function (item) { this.innerControlsOffset = item; this.updateDirty(); }; D.innerControlsOffset = function (item) { 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 && ['line', 'quadratic', 'bezier'].indexOf(item) >= 0) { this.curve = item; this.updateDirty(); } else { this.curve = 'bezier'; this.updateDirty(); } }; // #### Prototype functions // `cleanSpecies` - internal helper function - called by `prepareStamp` P.cleanSpecies = function () { this.dirtySpecies = false; let p = 'M0,0'; p = this.makeCogPath(); this.pathDefinition = p; }; // `makeCogPath` - internal helper function - called by `cleanSpecies` P.makeCogPath = function () { let {points, twist, outerRadius, innerRadius, outerControlsDistance, innerControlsDistance, outerControlsOffset, innerControlsOffset, curve} = this; let turn = 360 / points, xPts = [], currentTrailX, currentTrailY, currentPointX, currentPointY, currentLeadX, currentLeadY, controlStartX, controlStartY, deltaX, deltaY, controlEndX, controlEndY, myMin, myXoffset, myYoffset, i, myPath = ''; if (outerRadius.substring || innerRadius.substring || outerControlsDistance.substring || innerControlsDistance.substring || outerControlsOffset.substring || innerControlsOffset.substring) { let host = this.getHost(); if (host) { let [hW, hH] = 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; } } let 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; xPts.push(currentPointX); 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; xPts.push(currentPointX); 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; xPts.push(currentPointX); 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; xPts.push(currentPointX); 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; xPts.push(currentPointX); 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; xPts.push(currentPointX); 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; xPts.push(currentPointX); deltaY = parseFloat((innerPointTrail.y - currentPointY).toFixed(1)); currentPointY += deltaY; myPath += `${deltaX},${deltaY} `; deltaX = parseFloat((innerPoint.x - currentPointX).toFixed(1)); currentPointX += deltaX; xPts.push(currentPointX); deltaY = parseFloat((innerPoint.y - currentPointY).toFixed(1)); currentPointY += deltaY; myPath += `${deltaX},${deltaY} `; deltaX = parseFloat((innerPointLead.x - currentPointX).toFixed(1)); currentPointX += deltaX; xPts.push(currentPointX); 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; xPts.push(currentPointX); deltaY = parseFloat((outerPointTrail.y - currentPointY).toFixed(1)); currentPointY += deltaY; myPath += `${deltaX},${deltaY} `; deltaX = parseFloat((outerPoint.x - currentPointX).toFixed(1)); currentPointX += deltaX; xPts.push(currentPointX); deltaY = parseFloat((outerPoint.y - currentPointY).toFixed(1)); currentPointY += deltaY; myPath += `${deltaX},${deltaY} `; } } releaseVector(outerPoint, outerPointLead, outerPointTrail, innerPoint, innerPointLead, innerPointTrail); myMin = Math.min(...xPts); myXoffset = Math.abs(myMin).toFixed(1); if (curve == 'bezier') return `m${myXoffset},0c${myPath}z`; if (curve == 'quadratic') return `m${myXoffset},0q${myPath}z`; return `m${myXoffset},0l${myPath}z`; }; // #### Factories // ##### makeStar // 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', // }); // ``` const makeCog = function (items) { if (!items) return false; items.species = 'cog'; return new Cog(items); }; constructors.Cog = Cog; // #### Exports export { makeCog, };