From 4273579b17c737623897f0dd376f00268ff5eb58 Mon Sep 17 00:00:00 2001
From: Jozufozu <jozsefaug@gmail.com>
Date: Thu, 23 Dec 2021 13:17:25 -0800
Subject: [PATCH] Getting started

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+This wiki is a work in progress! Hopefully it can lead you in the right direction.
+
+Start by creating an empty subclass of `TileEntityInstance`, and build it up from there.
+```java
+public class MyBlockInstance extends TileEntityInstance<MyBlockEntity> {
+    
+    public MyBlockInstance(MaterialManager materialManager, MyBlockEntity tile) {
+        super(materialManager, tile);
+    }
+
+    @Override
+    public void remove() {
+        // You'll be doing some cleanup here later.
+    }
+}
+```
+And you have to register the `Instance` with Flywheel, so might as well get that out of the way now.
+```java
+public class MyInstances {
+    public static void init() {
+        InstancedRenderRegistry r = InstancedRenderRegistry.getInstance();
+        
+        r.tile(MyBlockEntityTypes.MY_BLOCK_ENTITY)
+                .setSkipRender(true) // Completely skip the BlockEntityRenderer.
+                .factory(MyBlockInstance::new); // Use our TileEntityInstance instead.
+    }
+}
+```
+And be sure to call `MyInstances.init()` somewhere!
+
+But, let's get back to the fun stuff. As it currently stands, our Instance does nothing but sit there and take up 
+memory. So, you might ask, how can I get it to render something?
+
+In Flywheel, `TileEntityInstance`s don't *technically* render models on their own. Instead, they ask the 
+`MaterialManager` to create a parameterized *instance* of a model. The `TileEntityInstance` is then free to change the 
+parameters, and Flywheel takes care of the rest, ensuring that your copy of the model is rendered in the right place, 
+with the right light, etc.
+
+So let's have your Instance ask the MaterialManager for a copy of some bricks, because why not?
+```java
+public class MyBlockInstance extends TileEntityInstance<MyBlockEntity> {
+    private final ModelData model;
+
+    public MyBlockInstance(MaterialManager materialManager, MyBlockEntity tile) {
+        super(materialManager, tile);
+
+        model = materialManager.defaultSolid()
+                .material(Materials.TRANSFORMED)
+                .getModel(Blocks.BRICKS.defaultBlockState()) // Feel free to use a different blockstate!
+                .createInstance();
+
+        // translate the model to make it appear at your BlockEntity
+        model.loadIdentity()
+                .translate(getInstancePosition());
+    }
+    
+    ...
+}
+```
+
+And now that you've acquired resources, you have to make sure to clean up after yourself!
+```java
+public class MyBlockInstance extends TileEntityInstance<MyBlockEntity> {
+    ...
+    
+    @Override
+    public void remove() {
+        model.delete();
+    }
+}
+```
+If you don't call `InstanceData#delete()`, all the models you ask for will be left behind when
+your block entity is broken.
+
+If you were to launch your game and place down your tile entity now, you'd see bricks, but they'd be very dark!
+
+That's because you never tell Flywheel how to light the bricks!
+
+In Flywheel, there's no need to query block and sky light every frame (like what's done for BlockEntityRenderers).
+Instead, light data can be stored in the `ModelData`, and updated as necessary. Flywheel already does most of the 
+heavy lifting here, it's just on you to make sure you update your parameters when Flywheel detects a light update. 
+You do this by overriding (drum roll...) `#updateLight`.
+
+```java
+public class MyBlockInstance extends TileEntityInstance<MyBlockEntity> {
+    ...
+    
+    @Override
+    public void updateLight() {
+        relight(getWorldPosition(), model);
+    }
+}
+```
+`relight(...)` is a helper method that takes a BlockPos and a series of model parameters, and updates the parameters 
+with the light data at the given position. 
+
+And so now your class looks like this:
+```java
+import com.jozufozu.flywheel.core.materials.model.ModelData;
+
+public class MyBlockInstance extends TileEntityInstance<MyBlockEntity> {
+
+    private final ModelData model;
+
+    public MyBlockInstance(MaterialManager materialManager, MyBlockEntity tile) {
+        super(materialManager, tile);
+
+        model = materialManager.defaultSolid()
+                .material(Materials.TRANSFORMED)
+                .getModel(Blocks.BRICKS.defaultBlockState())
+                .createInstance();
+        
+        model.loadIdentity()
+                .translate(getInstancePosition());
+    }
+
+    @Override
+    public void remove() {
+        model.delete();
+    }
+
+    @Override
+    public void updateLight() {
+        relight(getWorldPosition(), model);
+    }
+}
+```
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