I learned in an excellent school. They said ``if you can draw, you can write.''
Nonetheless, it's quite true that the links are very close between art and writing in ancient Egypt.
We have already seen some examples: the absence of determinative in captions, , shows a fundamental continuity between text and drawing. Likewise, we said (in 3.5) that if statues advance the left leg and not the right, it was because they were somehow three dimensional hieroglyphs.
On the other hand, hieroglyphs are also drawings, and they can retain this quality to add to the expressiveness of the text.
In later times, during the Ptolemaic and Roman era, this was used to an extreme extend, above all for god's names. The number of usable signs was much bigger than during the Pharaonic period; and lots of signs could be used alphabetically.
In Serge SAUNERON's Les prêtres de l'ancienne Égypte, (p. 138) the following example is given: Ptah, usually written , is written