TYPO Labs: DTL / URW++ session

During the DTL/URW++ session at the TYPO Labs conference on Wednesday 11 May 2016, Lukas Schneider gave an interesting talk on the LS Cadencer and the related LS Cadenculator (batch) fitting/auto-spacing extensions he has written in Python for Glyphs and RoboFont.

by Frank E. Blokland

As such, Lukas’ talk was actually a bit of a Trojan horse in a session that was mainly meant to focus on DTL OTMaster and the new FoundryMaster. However, I think this was in the spirit of this nice conference, where developers meet as colleagues and not as competitors.


TYPO-Berlin-2016-05-11-Norman-Posselt-0085© Norman Posselt / Monotype

Lukas Schneider studied graphic design at the Hochschule fur Gestaltung in Offenbach and holds a master’s degree in type design from the Type and Media department at the KABK. Lukas has designed typefaces for various type foundries, including FontFont, Lineto, and the Indian Type Foundry, as well as custom fonts for design agencies. At the Expert Class Type Design at the Plantin-Moretus Museum in Antwerp, he received a diploma with the highest distinction and got a deeper insight into my research about the standardisation of the Renaissance font production.

My PhD-research at Leiden University is conducted to test the hypothesis that Gutenberg and his consorts developed a standardised and even unitised system for producing textura type, and that this system was basically extrapolated for the production of roman type in Renaissance Italy. For this, Humanistic handwriting was literally molded into prefixed standardised proportions. Outcomes of my research prove that technical matters directly influenced the proportions of roman and italic type, and hence the related conditioning that forms the basis of our perception.

The patterns and structures distilled from the Renaissance archetypes can be used for education, and for the analysis and parametrisation of digital type. Present-day type designers are usually trained to do the spacing by the eye. However, the origin of conventions and our related conditioning of aesthetic preferences in type find their basis in Jenson’s technical constraints, as well as the technical considerations that propagated his patterns throughout the years.


TYPO-Berlin-2016-05-11-Norman-Posselt-0083© Norman Posselt / Monotype

The basis for the unitisation in the LS Cadencer tool is the stem interval, which is something textura and roman type have in common. To apply units for the positioning of the side bearings, pre-defined ‘CUST’ (Cadence Units Spacing Table) files are used. This might sound a bit complex and even cryptic, but the opposite is in fact the case: the LS Cadencer uses a simple but highly effective method for calculating the spacing in a mere jiffy. The effectiveness of the tool was demonstrated by Lukas when he spaced a typeface from one of the attendees on the fly. The parametrised spacing came extremely close to the original optical one. That does not have to come as a surprise, because what we judge optically finds its origin in the underlying patterning that is applied by the LS Cadencer.

The LS Cadenculator is a (batch) tool for measuring, analysing, and distilling cadence patterns from OpenType CFF fonts and Unified Font Object files. It works on .otf and/or .ufo files that are opened in Glyphs and RoboFont, or directly on folders containing the two aforementioned formats. The tool translates the fitting of characters into distances from either extremes on the x-axis or stems to the side bearings, which are then defined in cadence units. To do this, it uses the centre of the x-height for measurements by default, but a beam can be used here as well for altering the vertical point of measurement. The outcomes of the measurements are stored in CUST files; these files can be imported into the Cadencer tool and subsequently used for the spacing of fonts.

LS Cadenculator can generate CUST files based on the spacing measured in single fonts or in multiple fonts, in which case it will calculate the most commonly used spacing. The generated CUST files can be adapted in a text editor or directly in the LS Cadencer tool. Reports of the measurements can be stored in text files and as graphs in PDF format, as Lukas demonstrated.


Lukas’ talk was convincing enough for a representative of a very large company in the type business to invite him for a more detailed demonstration. Those who missed the session can find more related info here: http://typedrawers.com.


Written by Frank E. Blokland •