shape-points
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Generate points for simple shapes and curves: arcs, rectangles, rounded rectangles, circles, ellipses, bezierCurveTo, bezierCurveThrough (i.e., bezier curves through specific points)
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<h1 class="page-title">Source: quadraticCurveTo.js</h1>
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<pre class="prettyprint source linenums"><code>/**
* calculate points in a quadratic curve
* @module shape-points/quadraticCurveTo
* @param {number} x1 - starting point
* @param {number} y1
* @param {number} cp1x - control point
* @param {number} cp1y
* @param {number} x2 - ending point
* @param {number} y2
* @returns {array} [x1, y1, x2, y2, ... xn, yn]
*/
export function quadraticCurveTo(x1, y1, cp1x, cp1y, x2, y2, pointsInArc)
{
pointsInArc = pointsInArc || 5
const points = []
const interval = 1 / pointsInArc
for (let t = 0; t <= 1; t += interval)
{
const B0_t = Math.pow(1 - t, 2),
B1_t = 2 * t * (1 - t),
B2_t = Math.pow(t, 2)
points.push(
(B0_t * x1) + (B1_t * cp1x) + (B2_t * x2),
(B0_t * y1) + (B1_t * cp1y) + (B2_t * y2)
)
}
return points
}</code></pre>
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<h2><a href="index.html">Home</a></h2><h3>Modules</h3><ul><li><a href="module-shape-points.html">shape-points</a></li><li><a href="module-shape-points_arc.html">shape-points/arc</a></li><li><a href="module-shape-points_bezierCurveThrough.html">shape-points/bezierCurveThrough</a></li><li><a href="module-shape-points_bezierCurveTo.html">shape-points/bezierCurveTo</a></li><li><a href="module-shape-points_circle.html">shape-points/circle</a></li><li><a href="module-shape-points_ellipse.html">shape-points/ellipse</a></li><li><a href="module-shape-points_line.html">shape-points/line</a></li><li><a href="module-shape-points_quadraticCurveTo.html">shape-points/quadraticCurveTo</a></li><li><a href="module-shape-points_rect.html">shape-points/rect</a></li><li><a href="module-shape-points_roundedRect.html">shape-points/roundedRect</a></li></ul>
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Documentation generated by <a href="https://github.com/jsdoc/jsdoc">JSDoc 3.6.10</a> on Tue Mar 29 2022 14:31:03 GMT-0700 (Pacific Daylight Time)
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