[1.19.2] Change color of projectile at runtime

[DirtEngineer]

I have a gun that extends the BowItem.  It fires a slug that extends AbstractArrow.  The slug contains an arbitrary fluid.
I want to change the color of the slug based upon the color of the fluid that it contains at runtime.
I know of a scheme that sets it all up during registration.  There are a few issues with that.
1.  I would end up with some arbitrary number of projectiles to manage.  I could use an interface, but that won't solve the main problem.
2.   The asynchronous nature of the registration process.  How can I be sure that the fluids from the mod that mine depends upon or any future mods will all be there for me to make the various slugs.

The DynamicFluidContainerModel will allow me to change the color of the slug at runtime.  The problem is that I am unable to find any examples of its use.
Anyone have anything to help me?

Edited September 18, 2022 by DirtEngineer
Mistakes in text

[warjort]

I know virtually nothing about fluid rendering, but why wouldn't you retrieve the fluid color "lazily" either when you create the projectile or less efficiently during the rendering?

e.g. see how the arrow handles the potion color for tipped arrows (ID_EFFECT_COLOR).

[DirtEngineer]

That only changes the colors of the item.  it does that during registration. 

The arrow entity takes its effect based on the tipped arrow fired.  It doesn't change the appearance of the actual entity.

[warjort]

48 minutes ago, DirtEngineer said:

That only changes the colors of the item.  it does that during registration. 

The arrow entity takes its effect based on the tipped arrow fired.  It doesn't change the appearance of the actual entity.

It uses it for the particles and determining the texture to use. You can use it for the actual entity rendering.

I was just pointing out the pattern for setting the color at entity creation time and getting that data to the client.

[DirtEngineer]

The DynamicFluidContainerModel is looking more like the way to go here.
Could anyone provide information on how to use model loaders?