scrawl-canvas
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<h1 id="spiral-factory">Spiral factory</h1>
<p>A factory for generating spiral shape-based entitys</p>
<p>Path-defined entitys represent a diverse range of shapes rendered onto a DOM <canvas> element using the Canvas API’s <a href="https://developer.mozilla.org/en-US/docs/Web/API/Path2D">Path2D interface</a>. They use the <a href="../mixin/shapeBasic.html">shapeBasic</a> and <a href="../mixin/shapePathCalculation.html">shapePathCalculation</a> (some also use <a href="../mixin/shapeCurve.html">shapeCurve</a>) mixins to define much of their functionality.</p>
<p>All path-defined entitys can be positioned, cloned, filtered etc:</p>
<ul>
<li>Positioning functionality for the entity is supplied by the <strong>position</strong> mixin, while rendering functionality comes from the <strong>entity</strong> mixin. </li>
<li>Dimensions, however, have little meaning for path-defined entitys - their width and height are determined by their SVG path data Strings; use <code>scale</code> instead.</li>
<li>Path-defined entitys can use CSS color Strings for their fillStyle and strokeStyle values, alongside <strong>Gradient</strong>, <strong>RadialGradient</strong>, <strong>Color</strong> and <strong>Pattern</strong> objects. </li>
<li>They will also accept <strong>Filter</strong> objects.</li>
<li>They can use <strong>Anchor</strong> objects for user navigation. </li>
<li>They can be rendered to the canvas by including them in a <strong>Cell</strong> object’s <strong>Group</strong>. </li>
<li>They can be <strong>animated</strong> directly, or using delta animation, or act as the target for <strong>Tween</strong> animations.</li>
<li>Path-defined entitys can be cloned, and killed.</li>
</ul>
</div>
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<h4 id="using-path-defined-entitys-as-scrawl-canvas-paths">Using path-defined entitys as Scrawl-canvas paths</h4>
<p>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:</p>
<ul>
<li>To enable a path-defined entity to be used as a path by other artefacts, set its <code>useAsPath</code> flag to <code>true</code>.</li>
<li>The artefact can then set its <code>path</code> attribute to the path-defined entity’s name-String (or the entity itself), and set its <code>lockTo</code> Array values to <code>"path"</code>.</li>
<li>We position the artefact by setting its <code>pathPosition</code> attribute to a float Number value between <code>0.0 - 1.0</code>, with <code>0</code> being the start of the path, and <code>1</code> being its end.</li>
<li>Path-defined entitys can use other path-defined entitys as a path.</li>
<li>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.</li>
<li>Artefacts (and letters) can be rotated so that they match the rotation at that point along the path - <em><strong>tangential rotation</strong></em> by setting their <code>addPathRotation</code> flag to <code>true</code>.</li>
<li>Animate an artefact along the path by either using the artefact’s <code>delta</code> object, or triggering a Tween to perform the movement.</li>
</ul>
</div>
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<h4 id="demos">Demos:</h4>
<ul>
<li><a href="../../demo/canvas-011.html">Canvas-011</a> - Shape entity (make, clone, method); drag and drop shape entitys</li>
<li><a href="../../demo/canvas-012.html">Canvas-012</a> - Shape entity position; shape entity as a path for other artefacts to follow</li>
<li><a href="../../demo/canvas-013.html">Canvas-013</a> - Path-defined entitys: oval, rectangle, line, quadratic, bezier, tetragon, polygon, star, spiral</li>
<li><a href="../../demo/canvas-014.html">Canvas-014</a> - Line, quadratic and bezier entitys - control lock alternatives</li>
<li><a href="../../demo/canvas-018.html">Canvas-018</a> - Phrase entity - text along a path</li>
<li><a href="../../demo/canvas-024.html">Canvas-024</a> - Loom entity functionality</li>
<li><a href="../../demo/canvas-030.html">Canvas-030</a> - Polyline entity functionality</li>
<li><a href="../../demo/canvas-038.html">Canvas-038</a> - Responsive Shape-based entitys</li>
<li><a href="../../demo/dom-015.html">DOM-015</a> - Use stacked DOM artefact corners as pivot points</li>
<li><a href="../../demo/packets-002.html">Packets-002</a> - Scrawl-canvas packets - save and load a range of different entitys</li>
</ul>
</div>
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<h4 id="imports">Imports</h4>
</div>
<div class="content"><div class='highlight'><pre><span class="hljs-keyword">import</span> { constructors } <span class="hljs-keyword">from</span> <span class="hljs-string">'../core/library.js'</span>;
<span class="hljs-keyword">import</span> { mergeOver, Ωempty } <span class="hljs-keyword">from</span> <span class="hljs-string">'../core/utilities.js'</span>;
<span class="hljs-keyword">import</span> baseMix <span class="hljs-keyword">from</span> <span class="hljs-string">'../mixin/base.js'</span>;
<span class="hljs-keyword">import</span> shapeMix <span class="hljs-keyword">from</span> <span class="hljs-string">'../mixin/shapeBasic.js'</span>;</pre></div></div>
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<h4 id="spiral-constructor">Spiral constructor</h4>
</div>
<div class="content"><div class='highlight'><pre><span class="hljs-keyword">const</span> <span class="hljs-title class_">Spiral</span> = <span class="hljs-keyword">function</span> (<span class="hljs-params">items = Ωempty</span>) {
<span class="hljs-variable language_">this</span>.<span class="hljs-title function_">shapeInit</span>(items);
<span class="hljs-keyword">return</span> <span class="hljs-variable language_">this</span>;
};</pre></div></div>
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<h4 id="spiral-prototype">Spiral prototype</h4>
</div>
<div class="content"><div class='highlight'><pre><span class="hljs-keyword">let</span> P = <span class="hljs-title class_">Spiral</span>.<span class="hljs-property"><span class="hljs-keyword">prototype</span></span> = <span class="hljs-title class_">Object</span>.<span class="hljs-title function_">create</span>(<span class="hljs-title class_">Object</span>.<span class="hljs-property"><span class="hljs-keyword">prototype</span></span>);
P.<span class="hljs-property">type</span> = <span class="hljs-string">'Spiral'</span>;
P.<span class="hljs-property">lib</span> = <span class="hljs-string">'entity'</span>;
P.<span class="hljs-property">isArtefact</span> = <span class="hljs-literal">true</span>;
P.<span class="hljs-property">isAsset</span> = <span class="hljs-literal">false</span>;</pre></div></div>
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<h4 id="mixins">Mixins</h4>
<ul>
<li><a href="../mixin/base.html">base</a></li>
<li><a href="../mixin/shapeBasic.html">shapeBasic</a></li>
</ul>
</div>
<div class="content"><div class='highlight'><pre>P = <span class="hljs-title function_">baseMix</span>(P);
P = <span class="hljs-title function_">shapeMix</span>(P);</pre></div></div>
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<h4 id="spiral-attributes">Spiral attributes</h4>
<ul>
<li>Attributes defined in the <a href="../mixin/base.html">base mixin</a>: <strong>name</strong>.</li>
<li>Attributes defined in the <a href="../mixin/position.html">position mixin</a>: <strong>group, visibility, order, calculateOrder, stampOrder, start, <em>startX</em>, <em>startY</em>, handle, <em>handleX</em>, <em>handleY</em>, offset, <em>offsetX</em>, <em>offsetY</em>, dimensions, <em>width</em>, <em>height</em>, pivoted, mimicked, lockTo, <em>lockXTo</em>, <em>lockYTo</em>, scale, roll, noUserInteraction, noPositionDependencies, noCanvasEngineUpdates, noFilters, noPathUpdates, purge, bringToFrontOnDrag</strong>.</li>
<li>Attributes defined in the <a href="../mixin/delta.html">delta mixin</a>: <strong>delta, noDeltaUpdates</strong>.</li>
<li>Attributes defined in the <a href="../mixin/pivot.html">pivot mixin</a>: <strong>pivot, pivotCorner, addPivotHandle, addPivotOffset, addPivotRotation</strong>.</li>
<li>Attributes defined in the <a href="../mixin/mimic.html">mimic mixin</a>: <strong>mimic, useMimicDimensions, useMimicScale, useMimicStart, useMimicHandle, useMimicOffset, useMimicRotation, useMimicFlip, addOwnDimensionsToMimic, addOwnScaleToMimic, addOwnStartToMimic, addOwnHandleToMimic, addOwnOffsetToMimic, addOwnRotationToMimic</strong>.</li>
<li>Attributes defined in the <a href="../mixin/path.html">path mixin</a>: <strong>path, pathPosition, addPathHandle, addPathOffset, addPathRotation, constantPathSpeed</strong>.</li>
<li>Attributes defined in the <a href="../mixin/entity.html">entity mixin</a>: <strong>method, pathObject, winding, flipReverse, flipUpend, scaleOutline, lockFillStyleToEntity, lockStrokeStyleToEntity, onEnter, onLeave, onDown, onUp, <em>fillStyle, strokeStyle, globalAlpha, globalCompositeOperation, lineWidth, lineCap, lineJoin, lineDash, lineDashOffset, miterLimit, shadowOffsetX, shadowOffsetY, shadowBlur, shadowColor, filter</em></strong>.</li>
<li>Attributes defined in the <a href="../mixin/anchor.html">anchor mixin</a>: <strong>anchor</strong>.</li>
<li>Attributes defined in the <a href="../mixin/filter.html">filter mixin</a>: <strong>filters, isStencil</strong>.</li>
<li>Attributes defined in the <a href="../mixin/shapeBasic.html">shapeBasic mixin</a>: <strong>species, useAsPath, precision, pathDefinition, showBoundingBox, boundingBoxColor, minimumBoundingBoxDimensions, constantPathSpeed</strong>.</li>
</ul>
</div>
<div class="content"><div class='highlight'><pre><span class="hljs-keyword">let</span> defaultAttributes = {
<span class="hljs-attr">loops</span>: <span class="hljs-number">1</span>,
<span class="hljs-attr">loopIncrement</span>: <span class="hljs-number">1</span>,
<span class="hljs-attr">drawFromLoop</span>: <span class="hljs-number">0</span>,
};
P.<span class="hljs-property">defs</span> = <span class="hljs-title function_">mergeOver</span>(P.<span class="hljs-property">defs</span>, defaultAttributes);</pre></div></div>
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<h4 id="packet-management">Packet management</h4>
<p>No additional packet functionality required</p>
</div>
</li>
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<h4 id="clone-management">Clone management</h4>
<p>No additional clone functionality required</p>
</div>
</li>
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<h4 id="kill-management">Kill management</h4>
<p>No additional kill functionality required</p>
</div>
</li>
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<h4 id="get-set-deltaset">Get, Set, deltaSet</h4>
</div>
<div class="content"><div class='highlight'><pre><span class="hljs-keyword">let</span> S = P.<span class="hljs-property">setters</span>,
D = P.<span class="hljs-property">deltaSetters</span>;</pre></div></div>
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<p><strong>loops</strong></p>
</div>
<div class="content"><div class='highlight'><pre>S.<span class="hljs-property">loops</span> = <span class="hljs-keyword">function</span> (<span class="hljs-params">item</span>) {
<span class="hljs-variable language_">this</span>.<span class="hljs-property">loops</span> = item;
<span class="hljs-variable language_">this</span>.<span class="hljs-title function_">updateDirty</span>();
};
D.<span class="hljs-property">loops</span> = <span class="hljs-keyword">function</span> (<span class="hljs-params">item</span>) {
<span class="hljs-variable language_">this</span>.<span class="hljs-property">loops</span> += item;
<span class="hljs-variable language_">this</span>.<span class="hljs-title function_">updateDirty</span>();
};</pre></div></div>
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<p><strong>loopIncrement</strong></p>
</div>
<div class="content"><div class='highlight'><pre>S.<span class="hljs-property">loopIncrement</span> = <span class="hljs-keyword">function</span> (<span class="hljs-params">item</span>) {
<span class="hljs-variable language_">this</span>.<span class="hljs-property">loopIncrement</span> = item;
<span class="hljs-variable language_">this</span>.<span class="hljs-title function_">updateDirty</span>();
};
D.<span class="hljs-property">loopIncrement</span> = <span class="hljs-keyword">function</span> (<span class="hljs-params">item</span>) {
<span class="hljs-variable language_">this</span>.<span class="hljs-property">loopIncrement</span> += item;
<span class="hljs-variable language_">this</span>.<span class="hljs-title function_">updateDirty</span>();
};</pre></div></div>
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<p><strong>drawFromLoop</strong></p>
</div>
<div class="content"><div class='highlight'><pre>S.<span class="hljs-property">drawFromLoop</span> = <span class="hljs-keyword">function</span> (<span class="hljs-params">item</span>) {
<span class="hljs-variable language_">this</span>.<span class="hljs-property">drawFromLoop</span> = <span class="hljs-title class_">Math</span>.<span class="hljs-title function_">floor</span>(item);
<span class="hljs-variable language_">this</span>.<span class="hljs-title function_">updateDirty</span>();
};
D.<span class="hljs-property">drawFromLoop</span> = <span class="hljs-keyword">function</span> (<span class="hljs-params">item</span>) {
<span class="hljs-variable language_">this</span>.<span class="hljs-property">drawFromLoop</span> = <span class="hljs-title class_">Math</span>.<span class="hljs-title function_">floor</span>(<span class="hljs-variable language_">this</span>.<span class="hljs-property">drawFromLoop</span> + item);
<span class="hljs-variable language_">this</span>.<span class="hljs-title function_">updateDirty</span>();
};</pre></div></div>
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<h4 id="prototype-functions">Prototype functions</h4>
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<p><code>cleanSpecies</code> - internal helper function - called by <code>prepareStamp</code></p>
</div>
<div class="content"><div class='highlight'><pre>P.<span class="hljs-property">cleanSpecies</span> = <span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) {
<span class="hljs-variable language_">this</span>.<span class="hljs-property">dirtySpecies</span> = <span class="hljs-literal">false</span>;
<span class="hljs-keyword">let</span> p = <span class="hljs-string">'M0,0'</span>;
p = <span class="hljs-variable language_">this</span>.<span class="hljs-title function_">makeSpiralPath</span>();
<span class="hljs-variable language_">this</span>.<span class="hljs-property">pathDefinition</span> = p;
};</pre></div></div>
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<p>Magic numbers!</p>
<ul>
<li>These numbers produce an Archimedian spiral</li>
<li>The first loop has effective dimensions of 2px by 2px</li>
<li>Each additional loop increases the dimensions by 2px</li>
</ul>
</div>
<div class="content"><div class='highlight'><pre>P.<span class="hljs-property">firstTurn</span> = [
[<span class="hljs-number">0.043</span>, <span class="hljs-number">0</span>, <span class="hljs-number">0.082</span>, -<span class="hljs-number">0.035</span>, <span class="hljs-number">0.088</span>, -<span class="hljs-number">0.088</span>],
[<span class="hljs-number">0.007</span>, -<span class="hljs-number">0.057</span>, -<span class="hljs-number">0.024</span>, -<span class="hljs-number">0.121</span>, -<span class="hljs-number">0.088</span>, -<span class="hljs-number">0.162</span>],
[-<span class="hljs-number">0.07</span>, -<span class="hljs-number">0.045</span>, -<span class="hljs-number">0.169</span>, -<span class="hljs-number">0.054</span>, -<span class="hljs-number">0.265</span>, -<span class="hljs-number">0.015</span>],
[-<span class="hljs-number">0.106</span>, <span class="hljs-number">0.043</span>, -<span class="hljs-number">0.194</span>, <span class="hljs-number">0.138</span>, -<span class="hljs-number">0.235</span>, <span class="hljs-number">0.265</span>],
[-<span class="hljs-number">0.044</span>, <span class="hljs-number">0.139</span>, -<span class="hljs-number">0.026</span>, <span class="hljs-number">0.3</span>, <span class="hljs-number">0.058</span>, <span class="hljs-number">0.442</span>],
[<span class="hljs-number">0.091</span>, <span class="hljs-number">0.153</span>, <span class="hljs-number">0.25</span>, <span class="hljs-number">0.267</span>, <span class="hljs-number">0.442</span>, <span class="hljs-number">0.308</span>],
[<span class="hljs-number">0.206</span>, <span class="hljs-number">0.044</span>, <span class="hljs-number">0.431</span>, -<span class="hljs-number">0.001</span>, <span class="hljs-number">0.619</span>, -<span class="hljs-number">0.131</span>],
[<span class="hljs-number">0.2</span>, -<span class="hljs-number">0.139</span>, <span class="hljs-number">0.34</span>, -<span class="hljs-number">0.361</span>, <span class="hljs-number">0.381</span>, -<span class="hljs-number">0.619</span>]
];
P.<span class="hljs-property">subsequentTurns</span> = [
[<span class="hljs-number">0</span>, -<span class="hljs-number">0.27</span>, -<span class="hljs-number">0.11</span>, -<span class="hljs-number">0.52</span>, -<span class="hljs-number">0.29</span>, -<span class="hljs-number">0.71</span>],
[-<span class="hljs-number">0.19</span>, -<span class="hljs-number">0.19</span>, -<span class="hljs-number">0.44</span>, -<span class="hljs-number">0.29</span>, -<span class="hljs-number">0.71</span>, -<span class="hljs-number">0.29</span>],
[-<span class="hljs-number">0.27</span>, <span class="hljs-number">0</span>, -<span class="hljs-number">0.52</span>, <span class="hljs-number">0.11</span>, -<span class="hljs-number">0.71</span>, <span class="hljs-number">0.29</span>],
[-<span class="hljs-number">0.19</span>, <span class="hljs-number">0.19</span>, -<span class="hljs-number">0.29</span>, <span class="hljs-number">0.44</span>, -<span class="hljs-number">0.29</span>, <span class="hljs-number">0.71</span>],
[<span class="hljs-number">0</span>, <span class="hljs-number">0.27</span>, <span class="hljs-number">0.11</span>, <span class="hljs-number">0.52</span>, <span class="hljs-number">0.29</span>, <span class="hljs-number">0.71</span>],
[<span class="hljs-number">0.19</span>, <span class="hljs-number">0.19</span>, <span class="hljs-number">0.44</span>, <span class="hljs-number">0.29</span>, <span class="hljs-number">0.71</span>, <span class="hljs-number">0.29</span>],
[<span class="hljs-number">0.27</span>, <span class="hljs-number">0</span>, <span class="hljs-number">0.52</span>, -<span class="hljs-number">0.11</span>, <span class="hljs-number">0.71</span>, -<span class="hljs-number">0.29</span>],
[<span class="hljs-number">0.19</span>, -<span class="hljs-number">0.19</span>, <span class="hljs-number">0.29</span>, -<span class="hljs-number">0.44</span>, <span class="hljs-number">0.29</span>, -<span class="hljs-number">0.71</span>]
];</pre></div></div>
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<p><code>makeSpiralPath</code> - internal helper function - called by <code>cleanSpecies</code></p>
</div>
<div class="content"><div class='highlight'><pre>P.<span class="hljs-property">makeSpiralPath</span> = <span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) {
<span class="hljs-keyword">let</span> loops = <span class="hljs-title class_">Math</span>.<span class="hljs-title function_">floor</span>(<span class="hljs-variable language_">this</span>.<span class="hljs-property">loops</span>),
loopIncrement = <span class="hljs-variable language_">this</span>.<span class="hljs-property">loopIncrement</span>,
drawFromLoop = <span class="hljs-title class_">Math</span>.<span class="hljs-title function_">floor</span>(<span class="hljs-variable language_">this</span>.<span class="hljs-property">drawFromLoop</span>),
x1, y1, x2, y2, x3, y3,
sx1, sy1, sx2, sy2, sx3, sy3,
firstTurn = <span class="hljs-variable language_">this</span>.<span class="hljs-property">firstTurn</span>,
subsequentTurns = <span class="hljs-variable language_">this</span>.<span class="hljs-property">subsequentTurns</span>,
currentTurn = [];
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">0</span>; i < firstTurn.<span class="hljs-property">length</span>; i++) {
[x1, y1, x2, y2, x3, y3] = firstTurn[i];
currentTurn.<span class="hljs-title function_">push</span>([x1 * loopIncrement, y1 * loopIncrement, x2 * loopIncrement, y2 * loopIncrement, x3 * loopIncrement, y3 * loopIncrement]);
}
<span class="hljs-keyword">let</span> path = <span class="hljs-string">'m0,0'</span>;
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> j = <span class="hljs-number">0</span>; j < loops; j++) {
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">0</span>; i < currentTurn.<span class="hljs-property">length</span>; i++) {
[x1, y1, x2, y2, x3, y3] = currentTurn[i];
<span class="hljs-keyword">if</span> (j >= drawFromLoop) path += <span class="hljs-string">`c<span class="hljs-subst">${x1}</span>,<span class="hljs-subst">${y1}</span> <span class="hljs-subst">${x2}</span>,<span class="hljs-subst">${y2}</span> <span class="hljs-subst">${x3}</span>,<span class="hljs-subst">${y3}</span>`</span>;
[sx1, sy1, sx2, sy2, sx3, sy3] = subsequentTurns[i];
currentTurn[i] = [x1 + (sx1 * loopIncrement), y1 + (sy1 * loopIncrement), x2 + (sx2 * loopIncrement), y2 + (sy2 * loopIncrement), x3 + (sx3 * loopIncrement), y3 + (sy3 * loopIncrement)];
}
}
<span class="hljs-keyword">return</span> path;
};
P.<span class="hljs-property">calculateLocalPathAdditionalActions</span> = <span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) {
<span class="hljs-keyword">let</span> [x, y, w, h] = <span class="hljs-variable language_">this</span>.<span class="hljs-property">localBox</span>,
scale = <span class="hljs-variable language_">this</span>.<span class="hljs-property">scale</span>;
<span class="hljs-variable language_">this</span>.<span class="hljs-property">pathDefinition</span> = <span class="hljs-variable language_">this</span>.<span class="hljs-property">pathDefinition</span>.<span class="hljs-title function_">replace</span>(<span class="hljs-string">'m0,0'</span>, <span class="hljs-string">`m<span class="hljs-subst">${-x / scale}</span>,<span class="hljs-subst">${-y / scale}</span>`</span>);
<span class="hljs-variable language_">this</span>.<span class="hljs-property">pathCalculatedOnce</span> = <span class="hljs-literal">false</span>;</pre></div></div>
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<p>ALWAYS, when invoking <code>calculateLocalPath</code> from <code>calculateLocalPathAdditionalActions</code>, include the second argument, set to <code>true</code>! Failure to do this leads to an infinite loop which will make your machine weep.</p>
<ul>
<li>We need to recalculate the local path to take into account the offset required to put the Spiral 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.</li>
</ul>
</div>
<div class="content"><div class='highlight'><pre> <span class="hljs-variable language_">this</span>.<span class="hljs-title function_">calculateLocalPath</span>(<span class="hljs-variable language_">this</span>.<span class="hljs-property">pathDefinition</span>, <span class="hljs-literal">true</span>);
};</pre></div></div>
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<h4 id="factories">Factories</h4>
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<h5 id="makespiral">makeSpiral</h5>
<p>A spiral drawn from an inner-radius outwards by a given number of loops, with the distance between each loop determined by a given increment. Accepts argument with attributes:</p>
<ul>
<li><strong>loops</strong> (required) - positive float Number representing the number of times the Shape line will wind arount the Shape’s center point</li>
<li><strong>loopIncrement</strong> - float Number representative of the distance between successive loops; negative values have the effect of rotating the spiral 180 degrees</li>
<li><strong>drawFromLoop</strong> - positive integer Number representing the loop on which the spiral starts to be drawn</li>
</ul>
<pre><code>scrawl.<span class="hljs-title function_">makeSpiral</span>({
<span class="hljs-attr">name</span>: <span class="hljs-string">'mySpiral'</span>,
<span class="hljs-attr">strokeStyle</span>: <span class="hljs-string">'darkgreen'</span>,
<span class="hljs-attr">method</span>: <span class="hljs-string">'draw'</span>,
<span class="hljs-attr">startX</span>: <span class="hljs-number">50</span>,
<span class="hljs-attr">startY</span>: <span class="hljs-number">100</span>,
<span class="hljs-attr">loops</span>: <span class="hljs-number">5</span>,
<span class="hljs-attr">loopIncrement</span>: <span class="hljs-number">0.8</span>,
<span class="hljs-attr">drawFromLoop</span>: <span class="hljs-number">1</span>,
});
</code></pre>
</div>
<div class="content"><div class='highlight'><pre><span class="hljs-keyword">const</span> makeSpiral = <span class="hljs-keyword">function</span> (<span class="hljs-params">items</span>) {
<span class="hljs-keyword">if</span> (!items) <span class="hljs-keyword">return</span> <span class="hljs-literal">false</span>;
items.<span class="hljs-property">species</span> = <span class="hljs-string">'spiral'</span>;
<span class="hljs-keyword">return</span> <span class="hljs-keyword">new</span> <span class="hljs-title class_">Spiral</span>(items);
};
constructors.<span class="hljs-property">Spiral</span> = <span class="hljs-title class_">Spiral</span>;</pre></div></div>
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<h4 id="exports">Exports</h4>
</div>
<div class="content"><div class='highlight'><pre><span class="hljs-keyword">export</span> {
makeSpiral,
};</pre></div></div>
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