This script is very much a Phonological Cypher, being a phonetically constructed alphabet like others in that series. Here vowel shapes are used as the basis, then suffixes are added to show various transformations into consonantal forms. The vowel-base idea can be found in my Xylphika and Amethyst; the suffix style used here was inspired by Mattias Persson’s recent script Thabimande. The name comes from the day I designed it – Father’s Day in Thai.
The vowel space is divided in a rather geometric way, similar to the IPA but with only three degrees of front-back and close-open. An extra stroke is added to show rounding. The semivowels [j] and [w] are derived from [i] and [u]; the rhotic and lateral are derived from a theoretical “central” vowel shape. There is a mark to show nasalization (derived from the nasal consonant suffix, see below).
The various consonant types are conceived of as being transformations of vowel states. By adding constriction to a vowel point or approximant, we get a voiced fricative. By devoicing that we get an unvoiced fricative. By adding a sudden start to these we get affricates. By then taking away constriction noise and continuousness, we get plosives. Finally, by changing the flow of air from direct/pulmonic to indirect/pocketed, we get ejectives and implosives.
There is thus a progression from the most open and direct vowel state to each of the consonant types, and in this script suffixes with an increasing number of strokes show the degrees of transformation. Nasals are a little different, being continuous and constricted but also having an indirect flow of air. Thus the nasal suffix is a descender like the ejective and implosive suffixes. Note that the semivowel [l] above also has a descender, reflecting the indirect, lateral airflow.
Here the suffixes are shown in black with a vowel-base of [e] in green. These form a series of dental or forward alveolar articulations.
So the vowel-bases can imply, in a rough sense, the following consonantal locations. Alveolar [s] and [z] etc can be derived from the corner vowel [i], and labial [p] etc can be derived from the corner semivowel [w]. The postalveolar /sh/ and /zh/ can be derived from the rhotic [r] vowel. Thanks to Matthieu Frappe for pointing out the previous error here.
This is the first line of Shakespeare’s sonnet 18, for comparison with versions of SIGIL etc. Notice the economical measure of sharing the vowel-base in [mp].
Shall I compare thee to a summerís day?