© 2004-2012, v.8,
TypeCooker is a project by
Erik van Blokland,
LettError.com
TypeMedia.org

Digitisation

This is the process of reconstructing drawn shapes in digital lines and splines. This process is not necessarily exclusive to the TypeCooker assignment, any kind of shape can be drawn using Bezier paths.

The most common way to draw curves with modern software is using Bezier paths. Many programs use Bezier paths, you can find them in (for instance) Illustrator and PhotoShop, but also in specialised font programs as FontLab and Fontographer. Bezier paths have two kinds of points: the ones it passes through (on-curve), and points which influence the progress of the curve, but are not part of it, off-curve or “control points”.

Though any kind of shape can be constructed using these paths, the Bezier algorithm itself has a particular flavor and peculiarities. If you follow these guidelines for constructing the paths, you will be able to control the shapes in detail and with consistency. Even if you already have experience with drawing paths, it helps to take a look.

How many points do you need to capture the essence of the shape on paper? Subtle details in your drawings can get lost when you construct a path with too few points. Too many points on the other hand mean a lot more editing.

Some programs offer autotracing, a function which will convert a scanned image to a set of Bezier paths. While certainly quick, the results need lots of editing afterwards and often it's quicker to construct the paths by hand.

Basic path construction

bezier construction bezier construction

Place points on corners. Close all paths.

Curves

bezier construction

Make sure you have 2 control points for each curve segment. Look in the drawing tool info to find out how to add and manipulate control points.

bezier construction

For regular curve segments, the control points divide the curve roughly in thirds. This is not an exact requirement, but it makes sure the influence is balanced, which will make it easier to make changes.

bezier construction

Two curves connect in a broken way. Manipulate the control points of the center point to get the control points like this.

bezier construction

Two curves connect in a smooth way. If you move one control point, its twin on the opposite side will move in order to keep the connection smooth. The centre point is a flex point, it maintains a smooth connection between two opposing curves.

tangent points

Font editors offer a special class of points which guarantee a smooth connection between a curve and a straight segment. Illustrator does not have this kind of points. A tangent point has a smooth connection, but only one control point.

bezier construction

Identify horizontal and vertical extremes in the shape. These places need points. In a horizontal extreme any control points are vertically aligned. In a vertical extreme the control points will be horizontally aligned.

bezier construction

A round shape is then drawn as a closed path, with 4 curve points. Two on vertical extremes, two on horizontal extremes. The control points are vertically or horizontally aligned.

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Putting points around a shape is only the beginning. The next steps are about getting the digitised shape right. A lot of tweaking, printing, testing, looking, and trying.

Why

Bezier paths can be drawn in any number of ways. But in order to get reliable, consistent results it pays to stick to this method. You will learn to translate problems in shapes to point movements. Faster editing means drawing more letters, more iterations for design, better results.

Next

The next things to look into would be: