Add Support for UPC-A Barcodes

[primo-ppcg]

Hi, I would like to use the Viewer in my app for viewing the labels. It draws everything except UPC Barcode. Would it possible that you add UPC codes to the viewer aswell? This is the ZPL for my UPC Barcode (in Labelary it works):

^XA
^BY4,2,66^FO70,179^BUN,,Y,N,Y^FD1234567890000^FS
^XZ

Originally posted by @yatsek1 in #253

[kyleweishaupt]

Hi, I am running into this issue as well using the ^BUN command. My application can print and it shows up in the Labelary overlay, but not through the viewer. Hoping this feature can be implemented in the near future.

[ivanjx]

this is my attempt for UPC-A barcode. mostly just copy paste from the EAN-13 implementation with minor changes. keep in mind that in my branch i only use net6 and up.

ivanjx@43bb5f5

test:

^XA
^BY4,2,66^FO70,179^BUN,66,Y,N,Y^FD34567890000^FS
^XZ

output:

[ivanjx]

what i am not really sure is that the logic for drawing the guard bars. my current implementation is just based on my observation with limited set of samples.

ivanjx@43bb5f5#diff-004d2ae8ad9ea4a251a0e6620969160e253f5784e906a45462f0bcba71e2b7c5R102

[ivanjx]

UPC-A with extension: ivanjx@4836270

input:

^XA
^BY3
^FO100,100
^BUN,137
^FD07000002198^FS
^FO400,121
^BSN,117
^FD04414^FS
^XZ

output: