Added monochrome monospaced theme for better shapes control

[bondden]

This is a plain-styled theme with some features:

1. Monospaced fonts bring additional control on diagram layout and shapes widths
2. Some additional styling for Gantt

[The-Lum]

Hi @bondden, and all,

Here is a general remark.

The short names are good ($CLR_BG VS $BGCOLOR VS $PUML_BGCOLOR), ...
But it is not share with all theme!

Also @bondden:

• Perhaps don't use short name for external variable,
  only in a pinch for internal variable...

@ALL:
-> But which convention use between: $BGCOLOR VS $PUML_BGCOLOR...

@plantuml team, or any contributor:

• Make an inventory of the variable named management on all the current themes...
• Maybe a best practices guide should be created to help the developer to create new themes...

Regards.
Th.

[The-Lum]

Hi all,

From this part of code and from this example (tested on V1.2023.8beta1):

@startuml
title Test of the 'mono' theme

!theme mono

package "Some Group" {
  HTTP - [First Component]
  [Another Component]
}

node "Other Groups" {
  FTP - [Second Component]
  [First Component] --> FTP
}

cloud {
  [Example 1]
}

[Another Component] --> [Example 1]
@enduml

Is seems that fall-back-fonts is not so good used...

• Could you also manage font if Hack font is not installed on the hosted PlantUML?

Perhaps could you add a line like:

skinparam DefaultFontName ..., ..., ..., ...

But @arnaudroques, @plantuml team:

• What is the best syntax?
• It seems there are some issues...

KO with those lines

skinparam DefaultFontName Hack, DejaVu Sans Mono, Courier, monospaced

or

skinparam DefaultFontName "Hack", "DejaVu Sans Mono", "Courier", "monospaced"

Ref.

• Using fallback fonts #73
• https://forum.plantuml.net/10498/is-there-a-supported-way-to-specify-fall-back-fonts
• What is the best practice for `font name` definition on `skinparam` or `style`? #1264

Issues

• https://forum.plantuml.net/14842/specify-fall-back-fonts-is-not-working
• https://forum.plantuml.net/15533/new-function-%25font_exists

---

Regards.