[1.12] Getting itemstacks in inventory from client-side TESR?

[IceMetalPunk]

*Sigh* Rendering code is biting me in the butt again.

 

I have this TESR to render an item floating above a tile-entity providing block:

 

package com.icemetalpunk.totemaltarations.render;

import net.minecraft.client.Minecraft;
import net.minecraft.client.renderer.entity.RenderEntityItem;
import net.minecraft.client.renderer.tileentity.TileEntitySpecialRenderer;
import net.minecraft.entity.item.EntityItem;
import net.minecraft.init.Items;
import net.minecraft.item.ItemStack;
import net.minecraft.tileentity.TileEntityDropper;
import net.minecraftforge.items.IItemHandler;

public class AltarPedestalTESR extends TileEntitySpecialRenderer<TileEntityDropper> {

	protected final RenderEntityItem rei;
	protected final EntityItem entity = new EntityItem(Minecraft.getMinecraft().world, 0, 0, 0,
			new ItemStack(Items.TOTEM_OF_UNDYING, 1));
	protected int rotationControl = 0;
	protected final int INV_ROTATION_SPEED = 4;

	public AltarPedestalTESR() {
		super();
		rei = new RenderEntityItem(Minecraft.getMinecraft().getRenderManager(),
				Minecraft.getMinecraft().getRenderItem()) {
			@Override
			public boolean shouldSpreadItems() {
				return false;
			}
		};
	}

	@Override
	public void render(TileEntityDropper te, double x, double y, double z, float partialTicks, int destroyStage,
			float alpha) {

		entity.setWorld(te.getWorld());
		
		rotationControl = (rotationControl + 1) % this.INV_ROTATION_SPEED;
		if (rotationControl == 0) {
			entity.onUpdate();
		}

		this.setLightmapDisabled(true);
		rei.doRender(entity, x + 0.5, y + 1.0f, z + 0.5, 0, partialTicks);
		this.setLightmapDisabled(false);

	}

}

As you can see by the generic type parameter, I'm currently testing this by binding it to dropper tile entities.

 

It works perfectly fine! So my next step is to make it display the items that are actually in the inventory, instead of just the Totem of Undying. This is where things stopped working.

 

I figured it should be a simple change. In the render() method, just after the entity.setWorld() call, I added entity.setItem(te.getStackInSlot(0)). Simple, right? But then, it stopped rendering anything at all.

 

Some debugging later, and it turns out that getStackInSlot() is returning an empty ItemStack every time (with "air" as the item), regardless of the slot number, and even if I completely fill the inventory with things.

 

The TESR is being bound (and instantiated) only in my client proxy; I don't know if that has something to do with it? Shouldn't the client still have access to the inventory's contents? And if not, how would I go about rendering the inventory contents in the world in a TESR if the client can't access that information?

[Choonster]

The client and server each have their own copy of the TileEntity, only the server-side TileEntity loads and saves the inventory from NBT. If you want access to the inventory on the client side, you need to sync it with the TileEntity's update packet and update tag.

Edited September 16, 2017 by Choonster

[IceMetalPunk]

1 minute ago, Choonster said:

The client and server each have their own copy of the TileEntity, only the server-side TileEntity loads and saves the inventory from NBT. If you want access to the inventory on the client side, you need to sync it with the TileEntity's update packet and update tag.

Okay... I think I know how to do that for custom tile entities (it's been awhile since I've worked with TEs, but I believe I remember the gist of it), but how would I do that for vanilla TEs like droppers? (Looking into their code, the dropper TE seems not to override the default TileEntity getUpdatePacket() method which just returns null... and actually, if that's the case that there's no syncing, how does the client display the proper items in a dropper inventory, then? O_O )

[Choonster]

You'd need to send your own packet to sync the dropper's inventory contents with the clients tracking it.

 

There's no event fired when the inventory contents change, so you'd need to check every loaded dropper every tick to see if any of its inventory contents have changed since last tick. You should maintain a cache of each dropper's inventory contents using a custom capability.

 

The dropper and other vanilla inventories are synced through Containers, since the inventory contents only need to be known on the client side when a player has the GUI open. This won't work for your purposes since you need to know the inventory contents at all times to render them on the block.

Edited September 16, 2017 by Choonster

[IceMetalPunk]

Ah... well, that's only a minor hiccup. I was only planning on using the dropper TileEntity to test all my rendering code, and once it was 100%, I was going to start working on my custom TileEntity and just re-bind the renderer. Guess I can't do things in that order after all; I'll have to finish the TE first and then working on rendering code.

 

Thanks for your help!