Under the hood, learning code and math to draw curves



"These graphics were made using Sketch, SVG Animation, and some other nifty tricks"— Peter Nowell1

how Screenshot from interactive animation by Jason Davies illustrating how a parametric Bézier curve is constructed2

The variety of services that a designer is expected to offer, are multiplying. They will be asked to consider all of the environments in which a visual will appear (web, print, mobile, ...), and how to get it done properly, technically speaking. They are not only drawing the outside of the car, but also looking under the hood so to say. This is a change that is consistent with a line of work that relies so much on digital tools, but it seems important to accommodate some changes in education for example, for this change to be empowering and for designers to not end up in software dependent making.

Often enough, designers also have development skills. This means that they find themselves switching between visually oriented making, and code based making. This back and forth makes way for a space where the understanding of the properties of the digital material easily grows. The more rounded knowledge then influences both of the making spaces, cross nourishing the manipulations. We enter the terrain of specialists.

A simple example of this: manually editing svg code for web usage. The understanding that the one single visual curve gets encoded this way, goes a long way into researching and applying best practices, then reduces the amount of points by ensuring that all Bézier handles extend at 0 or 90 degrees to the planes.

perpendicular handles The curve above is created with the code below

id="layer1" transform="translate(-222.84229,-302.34058)" path style="fill:none;fill-rule:evenodd;stroke:#000000;stroke-width:1px; stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1" d="m 240.96981,486.44825 c 0,0 197.15712,-284.54733 197.15712,-108.31471 0,147.44026 99.79558,43.80725 99.79558,180.11885" id="path3336" connector-curvature="0" sodipodi:nodetypes="csc"


Autocad software allows interaction with code and visual output side by side.

As far as we can tell, CAD drawing tools have long ago internalised this practice of viewing mode along side code views. The XML editor3 is now available in Inkscape proposes this visual / code inspecting feature. We really feel like these are the views that let us ‘look under the hood’.

  1. Peter Nowell, Mastering the Bézier Curve in Sketch (2014) https://medium.com/sketch-app/mastering-the-bezier-curve-in-sketch-4da8fdf0dbbb 

  2. “These animations illustrate how a parametric Bézier curve is constructed. The parameter t ranges from 0 to 1. In the simplest case, a first-order Bézier curve, the curve is a straight line between the control points.” https://www.jasondavies.com/animated-bezier/ 

  3. Tavmjong Bah, Inkscape: Guide to a Vector Drawing Program http://tavmjong.free.fr/INKSCAPE/MANUAL/html/XML-Basic.html