PCB's data model does not allow arbitrary text in elements much beyond the refdes.

To get around this limitation, I wrote the following utility a few years ago

http://vk5hse.blogspot.com/2015/09/geda-pcb-footprint-text-utility.html

https://github.com/erichVK5/FootprintTextForPCB

Which also supports rendering of a few of the Hershey fonts, too.

By converting text into a footprint containing line features, these features can be used by itself or copied and combined with an existing footprint requiring labels, i.e. C B E for a transistor.

Without this utility, arbitrary text has to be hand drawn with line features in gEDA PCB.

The layout editor pcb-rnd has generalised the data model for footprints, now known as subcircuits, allowing multiple arbitrary text features, polygons and arcs. You simply select the features, and convert them to a subcircuit, which can be cut to buffer and saved as a standalone "footprint" for later re-use if necessary. pcb-rnd has also expanded the "terminal" options and internal "no connection" options for subcircuits for drc connectivity, even allowing pcb spiral inductors, for example, with electrical terminals at each end that do not behave like a short.

Regards,

Erich

On Sat, 16 Feb 2019 10:55 Girvin Herr (gherrl AT fastmail DOT com) [via geda-user AT delorie DOT com] <geda-user AT delorie DOT com wrote:

Greetings,

I am using pcb 4.1.3 on Slackware Linux.

I am trying to modify an existing, but renamed, element. I need to add
text ("+") to the top silk layer. The text gets added and looks to be on
the top silk layer, but when done and I choose "Convert selection to
element", the text disappears, even though it was selected. I confirmed
that the resulting element does not have the text on the top silk layer
when reloaded. However, when I look at the element file (below), I see
that the text statement is there but assigned to the "copper" layer 4,
not the "top silk" layer. What am I doing wrong or what is the trick to
get text on the top silk layer?

file:

Element["" "" "C?" "" 200.00mil 200.00mil 790.00mil -30.00mil 0 100 ""]
(
     Pin[-100.00mil 0.0000 65.00mil 30.00mil 71.00mil 35.00mil "" "1"
"edge2"]
     Pin[1700.00mil 0.0000 65.00mil 30.00mil 71.00mil 35.00mil "" "2"
"edge2"]
     ElementLine [700.00mil -50.00mil 900.00mil -50.00mil 10.00mil]
     ElementLine [900.00mil -50.00mil 900.00mil 50.00mil 10.00mil]
     ElementLine [900.00mil 50.00mil 700.00mil 50.00mil 10.00mil]
     ElementLine [700.00mil 50.00mil 700.00mil -50.00mil 10.00mil]
     ElementLine [0.0000 0.0000 700.00mil 0.0000 10.00mil]
     ElementLine [900.00mil 0.0000 1600.00mil 0.0000 10.00mil]

     )
Layer(4 "" "copper")
(
     Text[150.00mil 100.00mil 0 172 "+" "clearline"]
)

/file:

Note that when I load the element and check the groups in preferences,
there is only a "bottom silk" assigned to group 1 and "top silk"
assigned to group 2. What looks odd is that the "Top side" at the bottom
is set to Group 1 and the "Bottom side" is set to group 2. Just the
opposite. Is this correct?

Is there a good document for the element file statement definitions?
Mine is so old it does not list the "Layer" or "Text" statements.

Thanks.
Girvin Herr