[1.15.2] Rendering a Ship

[Obeeron]

Hello,
I would like to make a mod allowing you to build sailaible ships such as Archimedes’ Ships or Davinci's Vessels.
I would like to render the ship into its own dimension with few chunks loaded and then overlap the rendering of the oveworld and this other special dimension in which the ship would be.
However I really don't know what to search for and where to read about it so I'm hopping some of you may have ideas on how I could get started with this and what are the words I should search for.
Thanks

[Draco18s]

Good luck. This sort of thing is very complicated and you're not the only person trying to do this. I think there've been two others posting about it on this very forum in the last month.

[Obeeron]

Yep.. but I got a lot of time and motivation so anything would help. I'm not afraid of making a lot of researchs but I just have no idea of what I should look for and every mod that achieved that is in 1.12 or below. Once I know what to search for at least I'll get something to work on.

[Draco18s]

I searched "ship" and this was the second through fifth results

 

[Obeeron]

This was a previous post of mine but I switched to 1.15.2 so to avoid confusing people with the title and also because I'm not trying to move the blocks individually anymore, I decided to make a new post.

[Draco18s]

I apologize I should have recognize that. I swear someone else posted about it relatively recently as well, but the issue remains that you're going to be largely on your own.

[Obeeron]

Yes unfortunatly.. The thing is I when you search for things like "Minecraft forge world rendering" there is nothing helping that comes. So if I would even know the name of some classes of that may help or some kind of a mechanic I'm not aware of that I could try to research on, this would actually help so much because even if  I'll still have to do all the research for how to use it, I would have an idea of what to use. Cause right now I'm in that state where I'de like to start experimenting but I don't even know what to experiment with.
I'm just hopping for someone that already tried something like that to tell me "hey you should try to do that with that class, also beware that this will not work so go look for how to use that"

Edited June 17, 2020 by Obeeron

[Obeeron]

Little up ^^

[Ugdhar]

10 minutes ago, Obeeron said:

Little up ^^

Have you done any research or worked on this at all yourself since your last posting?

If you have, it would better promote your issue to share your findings/progress.

I think people would be more attracted to your issue if they felt you were actively pursuing it!

Edited June 22, 2020 by Ugdhar

[Obeeron]

Okay so I've managed to render a single block using MatrixStack and IRenderTypeBuffer but there are many things I used I don't understand how they really work such as :
- Why does rendering needs "IRenderTypeBuffer", why is it a buffer ??, does rendering uses multiple buffers ?
- What it the "Impl" class that implements IRenderTypeBuffer, what does it even stand for ?
- What is a MatrixStack ? I understood it's for translating blocks, rotating and scaling but why is it a stack, why do we need a "stack" for it ?

- Is BlockRendererDispatcher the best way to go for achieving rendering of moving structures ?

I've spent a long time going from classes to classes but it always come down to these questions that I can't find answer to.

[Draco18s]

1 minute ago, Obeeron said:

does rendering uses multiple buffers ?

Yes. Transparent things and opaque things need to be drawn in different passes as they have different sorting orders.

(The HUD is also a separate pass)

2 minutes ago, Obeeron said:

What it the "Impl" class that implements IRenderTypeBuffer, what does it even stand for ?

"Impl" is an abbreviation of "implementation." Use your IDE to find implementations of IRenderTypeBuffer.

3 minutes ago, Obeeron said:

What is a MatrixStack ? I understood it's for translating blocks, rotating and scaling but why is it a stack, why do we need a "stack" for it ?

Because you need several transformation matrices applied one after the other to handle certain types of rendering. Think about an item that lays flat on the top surface of a block (campfires do this). The item renderer assumes that the item sticks up vertically but the campfire wants to render it horizontally. We already have a transformation matrix to counteract the player's position away from 0,0,0 but now we need another one to rotate the item to lay flat...

 

[Obeeron]

Okay so right now I get an instance of the buffer with :

Impl renderTypeBuffer = IRenderTypeBuffer.getImpl(Tessellator.getInstance().getBuffer());

So if I'm correct, I'm using Tessellator's buffer (what is it usually used for ?) and you said that :

Quote

Transparent things and opaque things need to be drawn in different passes as they have different sorting orders

So using only this instance of Tessellator's buffer, will I be able to render both solid blocks and transparent blocks ?

Regarding MatrixStack, looking at the code, when using matrixStack.push() it just clones the last entry, and when doing matrixStack.pop() it just removes it. So its only purpose here is to be passed as parameter for "blockRendererDispatcher.getBlockModelRenderer().renderModel(..., matrixStack, ...)", so, correct me if I'm wrong, as I'm only using one "Entry" (because I only do one push/pop) and because all operations such as translate, scale, rotate, only affect the last entry without creating a new one, the stack structure isn't really needed here, it would only be needed in special cases that I won't have to interact with right ?

[Draco18s]

I've never dug into the rendering system more than I need to, which means I've never messed with the things you're messing with.