Add an option to hide tempo markings and bar numbers

[creature]

Hello!

I'm using AlphaTex to render some simple scales and exercises. I'd like to have the option of hiding the tempo marking ("♩ = 120") for cases like this. My page text says to play the scale slowly and evenly, and an explicit tempo marking makes a "target speed" suggestion I'd like to avoid.

I also have cases where the notation is more for illustration than playing, so the tempo marking is a distraction. For instance: "A major scale is made up of 8 notes: [notation]. We can build triads from these scale notes: [notation]."

Similarly, I'd like an option to hide bar numbers. A lot of these scales/exercises/illustrations are only 1 or 2 bars long, so bar numbers don't add any useful information. (Piano music often prints bar numbers at the start of each new stave line – it would be neat to have this option, and/or "print a bar number every n bars", but I don't currently need this.)

If you agree that optionally hiding tempo and/or bar numbers would be useful, I can probably open a pull request for those. :) Thanks!

[Danielku15]

Hey.

For hiding the tempo you can already use https://alphatab.net/docs/reference/settings/notation/elements with NotationElement.EffectTempo. alphaTab 1.7 will also have an option to hide individual tempo markers (expressed via alphaTex or manually on the data model).

For bar numbers there is no good feature yet. Temporarily until such a feature is added, you could configure the color to be transparent.

Globally via
https://alphatab.net/docs/reference/settings/display/resources (barNumberColor) or individually on bars via https://alphatab.net/docs/guides/coloring.

I think it makes sense to add a new option to configure the bar number display. I'll have to check the different file formats how they currently contain this info. I think a combination of a general setting (show, hide, on first bar of system) and overrides on model level (masterbar?) make sense.

Any contributions are welcome 😁

[creature]

Thanks! I didn't know about these options, so it was useful. I'm looking forward to the alphaTex option in v1.7.

I'll try to find that option and implement something similar for bar numbers, but no promises. I'll open a PR if I succeed.

For anyone else who wants to hide the tempo and bar numbers, my JavaScript was basically this:

const settings = {
  notation: {
    elements: {
      effectTempo: false
    }
  },
  display: {
    resources: {
      barNumberColor: '#FFF0'
    }
  }
};
const el = document.querySelector("#tab");
const api = new alphaTab.AlphaTabApi(el, settings);
const notes = el.getAttribute("data-notes") || "";
api.tex(notes);

[Danielku15]

Added #2398 to track the feature of customizing the bar number display.