game_menu entity

[Blixibon]

This PR adds a new entity called game_menu which displays a custom dialog from CHudMenu, which is normally used by multiplayer games to initiate voice commands.

Example:

This PR also contains some changes to CHudMenu which are associated with this entity.

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PR Checklist

• My PR follows all guidelines in the CONTRIBUTING.md file
• My PR targets a develop branch OR targets another branch with a specific goal in mind

[Blixibon]

I've been told that INVALID_MENUITEM being set at -1 instead of 0 may break SourceMod plugins. Putting this in draft until I have a better solution

[Blixibon]

I've been told that INVALID_MENUITEM being set at -1 instead of 0 may break SourceMod plugins. Putting this in draft until I have a better solution

Following up from this: The invalid menu item was changed from 0 to -1 so that the paint code could differentiate between the title and the 10th/cancel option, which both use an item ID of 0. Without this, the cancel option would use the larger font intended for the title.

In order to get around the aforementioned plugin incompatibility, I made the paint code differentiate between them in a way that allows their IDs to remain the same. If the item ID is 0 and it contains "0." at the start of the text, then it is considered a menu item. If the item ID is 0 and it does not contain "0." at the start, then it is considered the title.

I am aware that this is a bit of a hack and only differentiates them implicitly. If the title happens to contain "0." at the start, then it will be considered a menu item, although this simply makes it use the smaller font and has no other negative effects. Since there is already an explicit 10th option that corresponds to "0.", I don't expect this to be a significant problem.

Perhaps there could be a more proper way to apply one font over the other in the future, although I don't see that being in the current scope of this feature.

[samisalreadytaken]

Using control characters (a la terminal escape codes) would be compatible with plugins (nobody would send non-printable characters) and open up the possibilities of any kind of customisation, not limited to text changes.

For example it could be "\x01" to denote title case, "\x1BB;" for bold text, "\x1BCRRGGBB;" to colour, etc..

[azzyr]

This looks good to me after the refactor for INVALID_MENUITEM. This could potentially be improved in the future with support for pagination