Reorganize and simplify

- StructTypes no longer need to be registered
 - Move backend.source to core.source
 - Move GameStateRegistry to core
 - Backend is static again
 - Loader maintains state internally

src/main/java/com/jozufozu/flywheel/FlywheelClient.java

@@ -1,8 +1,8 @@
 package com.jozufozu.flywheel;
 
 import com.jozufozu.flywheel.backend.Backend;
+import com.jozufozu.flywheel.backend.OptifineHandler;
 import com.jozufozu.flywheel.core.Contexts;
-import com.jozufozu.flywheel.core.Materials;
 import com.jozufozu.flywheel.core.PartialModel;
 import com.jozufozu.flywheel.core.StitchedSprite;
 import com.jozufozu.flywheel.core.compile.ProgramCompiler;
@@ -18,15 +18,14 @@ import net.minecraftforge.fml.javafmlmod.FMLJavaModLoadingContext;
 public class FlywheelClient {
 
 	public static void clientInit() {
-		CrashReportCallables.registerCrashCallable("Flywheel Backend", () ->
+		CrashReportCallables.registerCrashCallable("Flywheel Backend", Backend::getBackendDescriptor);
-				Backend.getInstance().getBackendDescriptor());
 
+		OptifineHandler.init();
 		Backend.init();
 		IEventBus modEventBus = FMLJavaModLoadingContext.get()
 				.getModEventBus();
 
 		modEventBus.addListener(Contexts::flwInit);
-		modEventBus.addListener(Materials::flwInit);
 		modEventBus.addListener(PartialModel::onModelRegistry);
 		modEventBus.addListener(PartialModel::onModelBake);
 		modEventBus.addListener(StitchedSprite::onTextureStitchPre);

src/main/java/com/jozufozu/flywheel/backend/Backend.java

@@ -1,19 +1,11 @@
 package com.jozufozu.flywheel.backend;
 
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.Map;
-
 import javax.annotation.Nullable;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
-import org.lwjgl.opengl.GL;
-import org.lwjgl.opengl.GLCapabilities;
 
 import com.jozufozu.flywheel.api.FlywheelWorld;
-import com.jozufozu.flywheel.api.InstanceData;
-import com.jozufozu.flywheel.api.struct.StructType;
 import com.jozufozu.flywheel.backend.gl.versioned.GlCompat;
 import com.jozufozu.flywheel.config.FlwConfig;
 import com.jozufozu.flywheel.config.FlwEngine;
@@ -27,89 +19,39 @@ import net.minecraft.world.level.LevelAccessor;
 public class Backend {
 	public static final Logger LOGGER = LogManager.getLogger(Backend.class);
 
-	protected static final Backend INSTANCE = new Backend();
+	private static FlwEngine engine;
-	public static Backend getInstance() {
-		return INSTANCE;
-	}
 
-	private FlwEngine engine;
+	public static GlCompat compat;
 
-	public GLCapabilities capabilities;
+	private static final Loader loader = new Loader();
-	public GlCompat compat;
-
-	public final Loader loader;
-	private final Map<ResourceLocation, StructType<?>> materialRegistry = new HashMap<>();
-	private final Map<ResourceLocation, ProgramSpec> programSpecRegistry = new HashMap<>();
-
-	protected Backend() {
-		loader = new Loader(this);
-
-		OptifineHandler.init();
-	}
 
 	/**
 	 * Get a string describing the Flywheel backend. When there are eventually multiple backends
 	 * (Meshlet, MDI, GL31 Draw Instanced are planned), this will name which one is in use.
 	 */
-	public String getBackendDescriptor() {
+	public static String getBackendDescriptor() {
 		return engine == null ? "" : engine.getProperName();
 	}
 
-	public FlwEngine getEngine() {
+	public static FlwEngine getEngine() {
 		return engine;
 	}
 
-	/**
-	 * Register a shader program.
-	 */
-	public ProgramSpec register(ProgramSpec spec) {
-		ResourceLocation name = spec.name;
-		if (programSpecRegistry.containsKey(name)) {
-			throw new IllegalStateException("Program spec '" + name + "' already registered.");
-		}
-		programSpecRegistry.put(name, spec);
-		return spec;
-	}
-
-	/**
-	 * Register an instancing material.
-	 */
-	public <D extends InstanceData> StructType<D> register(ResourceLocation name, StructType<D> spec) {
-		if (materialRegistry.containsKey(name)) {
-			throw new IllegalStateException("Material spec '" + name + "' already registered.");
-		}
-		materialRegistry.put(name, spec);
-
-		LOGGER.debug("registered material '" + name + "' with instance size " + spec.getLayout().getStride());
-
-		return spec;
-	}
-
 	@Nullable
-	public ProgramSpec getSpec(ResourceLocation name) {
+	public static ProgramSpec getSpec(ResourceLocation name) {
-		return programSpecRegistry.get(name);
+		return loader.get(name);
 	}
 
-	public void refresh() {
+	public static void refresh() {
 		OptifineHandler.refresh();
 
-		capabilities = GL.createCapabilities();
+		compat = new GlCompat();
-
-		compat = new GlCompat(capabilities);
 
 		engine = chooseEngine(compat);
 	}
 
-	public Collection<StructType<?>> allMaterials() {
-		return materialRegistry.values();
-	}
-
-	public Collection<ProgramSpec> allPrograms() {
-		return programSpecRegistry.values();
-	}
-
 	public static boolean isOn() {
-		return getInstance().engine != FlwEngine.OFF;
+		return engine != FlwEngine.OFF;
 	}
 
 	public static boolean canUseInstancing(@Nullable Level world) {
@@ -137,18 +79,6 @@ public class Backend {
 		RenderWork.enqueue(Minecraft.getInstance().levelRenderer::allChanged);
 	}
 
-	/**
-	 * INTERNAL USE ONLY
-	 */
-	void _clearContexts() {
-		GameStateRegistry.clear();
-		programSpecRegistry.clear();
-		materialRegistry.clear();
-	}
-
-	public static void init() {
-	}
-
 	private static FlwEngine chooseEngine(GlCompat compat) {
 		FlwEngine preferredChoice = FlwConfig.get()
 				.getEngine();
@@ -162,4 +92,12 @@ public class Backend {
 
 		return canUseEngine ? preferredChoice : FlwEngine.OFF;
 	}
+
+	public static void init() {
+		// noop
+	}
+
+	private Backend() {
+		throw new UnsupportedOperationException("Backend is a static class!");
+	}
 }

src/main/java/com/jozufozu/flywheel/backend/Loader.java

@@ -1,15 +1,20 @@
 package com.jozufozu.flywheel.backend;
 
 import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+
+import javax.annotation.Nullable;
 
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.google.gson.JsonElement;
 import com.jozufozu.flywheel.backend.instancing.InstancedRenderDispatcher;
-import com.jozufozu.flywheel.backend.source.Resolver;
+import com.jozufozu.flywheel.core.GameStateRegistry;
-import com.jozufozu.flywheel.backend.source.ShaderSources;
 import com.jozufozu.flywheel.core.crumbling.CrumblingRenderer;
 import com.jozufozu.flywheel.core.shader.ProgramSpec;
+import com.jozufozu.flywheel.core.source.Resolver;
+import com.jozufozu.flywheel.core.source.ShaderSources;
 import com.jozufozu.flywheel.event.GatherContextEvent;
 import com.jozufozu.flywheel.util.ResourceUtil;
 import com.jozufozu.flywheel.util.StringUtil;
@@ -37,13 +42,11 @@ public class Loader implements ResourceManagerReloadListener {
 	public static final String PROGRAM_DIR = "flywheel/programs/";
 	private static final Gson GSON = new GsonBuilder().create();
 
-	private final Backend backend;
+	private final Map<ResourceLocation, ProgramSpec> programSpecRegistry = new HashMap<>();
 
 	private boolean firstLoad = true;
 
-	public Loader(Backend backend) {
+	Loader() {
-		this.backend = backend;
-
 		// Can be null when running datagenerators due to the unfortunate time we call this
 		Minecraft minecraft = Minecraft.getInstance();
 		if (minecraft != null) {
@@ -54,15 +57,20 @@ public class Loader implements ResourceManagerReloadListener {
 		}
 	}
 
+	@Nullable
+	public ProgramSpec get(ResourceLocation name) {
+		return programSpecRegistry.get(name);
+	}
+
 	@Override
 	public void onResourceManagerReload(ResourceManager manager) {
-		backend.refresh();
+		Backend.refresh();
 
-		backend._clearContexts();
+		GameStateRegistry._clear();
 
 		Resolver.INSTANCE.invalidate();
 		ModLoader.get()
-				.postEvent(new GatherContextEvent(backend, firstLoad));
+				.postEvent(new GatherContextEvent(firstLoad));
 
 		ShaderSources sources = new ShaderSources(manager);
 
@@ -101,10 +109,21 @@ public class Loader implements ResourceManagerReloadListener {
 
 				spec.setName(specName);
 
-				backend.register(spec);
+				register(spec);
 			} catch (Exception e) {
 				Backend.LOGGER.error(e);
 			}
 		}
 	}
+
+	/**
+	 * Register a shader program.
+	 */
+	private void register(ProgramSpec spec) {
+		ResourceLocation name = spec.name;
+		if (programSpecRegistry.containsKey(name)) {
+			throw new IllegalStateException("Program spec '" + name + "' already registered.");
+		}
+		programSpecRegistry.put(name, spec);
+	}
 }

src/main/java/com/jozufozu/flywheel/backend/gl/buffer/GlBuffer.java

@@ -21,7 +21,7 @@ public abstract class GlBuffer extends GlObject {
 	 * @return A buffer that will be persistent if the driver supports it.
 	 */
 	public static GlBuffer requestPersistent(GlBufferType type) {
-		if (Backend.getInstance().compat.bufferStorageSupported()) {
+		if (Backend.compat.bufferStorageSupported()) {
 			return new PersistentGlBuffer(type);
 		} else {
 			return new MappedGlBuffer(type);

src/main/java/com/jozufozu/flywheel/backend/gl/buffer/PersistentGlBuffer.java

@@ -46,7 +46,7 @@ public class PersistentGlBuffer extends GlBuffer implements Mappable {
 
 		fence.clear();
 
-		Backend.getInstance().compat.bufferStorage.bufferStorage(type, size, flags);
+		Backend.compat.bufferStorage.bufferStorage(type, size, flags);
 
 		ByteBuffer byteBuffer = GL30.glMapBufferRange(type.glEnum, 0, size, flags);
 

src/main/java/com/jozufozu/flywheel/backend/gl/shader/GlShader.java

@@ -4,7 +4,7 @@ import org.lwjgl.opengl.GL20;
 
 import com.jozufozu.flywheel.backend.gl.GlObject;
 import com.jozufozu.flywheel.backend.gl.versioned.GlCompat;
-import com.jozufozu.flywheel.backend.source.ShaderLoadingException;
+import com.jozufozu.flywheel.core.source.ShaderLoadingException;
 
 import net.minecraft.resources.ResourceLocation;
 

src/main/java/com/jozufozu/flywheel/backend/gl/versioned/GlCompat.java

@@ -4,6 +4,7 @@ import java.nio.ByteBuffer;
 import java.util.Arrays;
 
 import org.lwjgl.PointerBuffer;
+import org.lwjgl.opengl.GL;
 import org.lwjgl.opengl.GL20C;
 import org.lwjgl.opengl.GLCapabilities;
 import org.lwjgl.system.MemoryStack;
@@ -23,11 +24,11 @@ public class GlCompat {
 	public final BufferStorage bufferStorage;
 	public final boolean amd;
 
-	public GlCompat(GLCapabilities caps) {
+	public GlCompat() {
+		GLCapabilities caps = GL.createCapabilities();
 		instancedArrays = getLatest(InstancedArrays.class, caps);
 		bufferStorage = getLatest(BufferStorage.class, caps);
 
-
 		if (Util.getPlatform() == Util.OS.WINDOWS) {
 			String vendor = GL20C.glGetString(GL20C.GL_VENDOR);
 			// vendor string I got was "ATI Technologies Inc."

src/main/java/com/jozufozu/flywheel/backend/instancing/InstanceWorld.java

@@ -39,8 +39,7 @@ public class InstanceWorld {
 		this.taskEngine = new ParallelTaskEngine("Flywheel " + world.dimension().location());
 		this.taskEngine.startWorkers();
 
-		FlwEngine engine = Backend.getInstance()
+		FlwEngine engine = Backend.getEngine();
-				.getEngine();
 
 		switch (engine) {
 		case INSTANCING -> {

src/main/java/com/jozufozu/flywheel/backend/instancing/instancing/GPUInstancer.java

@@ -198,7 +198,7 @@ public class GPUInstancer<D extends InstanceData> extends AbstractInstancer<D> {
 		vao.bindAttributes(attributeBaseIndex, instanceFormat);
 
 		for (int i = 0; i < instanceFormat.getAttributeCount(); i++) {
-			Backend.getInstance().compat.instancedArrays.vertexAttribDivisor(attributeBaseIndex + i, 1);
+			Backend.compat.instancedArrays.vertexAttribDivisor(attributeBaseIndex + i, 1);
 		}
 	}
 }

src/main/java/com/jozufozu/flywheel/backend/instancing/instancing/InstancedMaterialGroup.java

@@ -37,7 +37,7 @@ public class InstancedMaterialGroup<P extends WorldProgram> implements MaterialG
 	public InstancedMaterialGroup(InstancingEngine<P> owner, RenderType type) {
 		this.owner = owner;
 		this.type = type;
-		if (Backend.getInstance().compat.onAMDWindows()) {
+		if (Backend.compat.onAMDWindows()) {
 			this.allocator = FallbackAllocator.INSTANCE;
 		} else {
 			this.allocator = new ModelPool(Formats.POS_TEX_NORMAL, 2048);

src/main/java/com/jozufozu/flywheel/core/Contexts.java

@@ -1,13 +1,12 @@
 package com.jozufozu.flywheel.core;
 
 import com.jozufozu.flywheel.Flywheel;
-import com.jozufozu.flywheel.backend.GameStateRegistry;
-import com.jozufozu.flywheel.backend.source.FileResolution;
-import com.jozufozu.flywheel.backend.source.Resolver;
 import com.jozufozu.flywheel.core.compile.ProgramCompiler;
 import com.jozufozu.flywheel.core.crumbling.CrumblingProgram;
 import com.jozufozu.flywheel.core.shader.NormalDebugStateProvider;
 import com.jozufozu.flywheel.core.shader.WorldProgram;
+import com.jozufozu.flywheel.core.source.FileResolution;
+import com.jozufozu.flywheel.core.source.Resolver;
 import com.jozufozu.flywheel.event.GatherContextEvent;
 import com.jozufozu.flywheel.util.ResourceUtil;
 

src/main/java/com/jozufozu/flywheel/core/GameStateRegistry.java

@@ -1,10 +1,10 @@
-package com.jozufozu.flywheel.backend;
+package com.jozufozu.flywheel.core;
 
 import java.util.HashMap;
 import java.util.Map;
 
-import com.jozufozu.flywheel.core.compile.ShaderConstants;
 import com.jozufozu.flywheel.core.shader.GameStateProvider;
+import com.jozufozu.flywheel.core.shader.ShaderConstants;
 import com.jozufozu.flywheel.core.shader.StateSnapshot;
 
 import net.minecraft.resources.ResourceLocation;
@@ -13,7 +13,7 @@ public class GameStateRegistry {
 
 	private static final Map<ResourceLocation, GameStateProvider> registeredStateProviders = new HashMap<>();
 
-	static void clear() {
+	public static void _clear() {
 		registeredStateProviders.clear();
 	}
 

src/main/java/com/jozufozu/flywheel/core/Materials.java

@@ -2,12 +2,10 @@ package com.jozufozu.flywheel.core;
 
 import com.jozufozu.flywheel.Flywheel;
 import com.jozufozu.flywheel.api.struct.StructType;
-import com.jozufozu.flywheel.backend.Backend;
 import com.jozufozu.flywheel.core.materials.model.ModelData;
 import com.jozufozu.flywheel.core.materials.model.ModelType;
 import com.jozufozu.flywheel.core.materials.oriented.OrientedData;
 import com.jozufozu.flywheel.core.materials.oriented.OrientedType;
-import com.jozufozu.flywheel.event.GatherContextEvent;
 
 import net.minecraft.resources.ResourceLocation;
 import net.minecraftforge.api.distmarker.Dist;
@@ -19,12 +17,6 @@ public class Materials {
 	public static final StructType<OrientedData> ORIENTED = new OrientedType();
 	public static final StructType<ModelData> TRANSFORMED = new ModelType();
 
-	public static void flwInit(GatherContextEvent event) {
-		Backend backend = event.getBackend();
-		backend.register(Names.ORIENTED, ORIENTED);
-		backend.register(Names.MODEL, TRANSFORMED);
-	}
-
 	public static class Names {
 		public static final ResourceLocation MODEL = Flywheel.rl("model");
 		public static final ResourceLocation ORIENTED = Flywheel.rl("oriented");

src/main/java/com/jozufozu/flywheel/core/compile/CompileUtil.java

@@ -1,10 +1,16 @@
 package com.jozufozu.flywheel.core.compile;
 
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
 import com.jozufozu.flywheel.backend.gl.GLSLVersion;
 import com.jozufozu.flywheel.backend.gl.shader.ShaderType;
 
 public class CompileUtil {
 
+	public static final Pattern vecType = Pattern.compile("^[biud]?vec([234])$");
+	public static final Pattern matType = Pattern.compile("^mat([234])(?:x([234]))?$");
+
 	protected static String generateHeader(GLSLVersion version, ShaderType type) {
 		return "#version "
 				+ version
@@ -13,4 +19,31 @@ public class CompileUtil {
 				+ "#extension GL_ARB_conservative_depth : enable\n"
 				+ type.getDefineStatement();
 	}
+
+	public static int getElementCount(String type) {
+		Matcher vec = vecType.matcher(type);
+		if (vec.find()) return Integer.parseInt(vec.group(1));
+
+		Matcher mat = matType.matcher(type);
+		if (mat.find()) {
+			int n = Integer.parseInt(mat.group(1));
+
+			String m = mat.group(2);
+
+			if (m != null) return Integer.parseInt(m) * n;
+
+			return n;
+		}
+
+		return 1;
+	}
+
+	public static int getAttributeCount(CharSequence type) {
+		Matcher mat = matType.matcher(type);
+		if (mat.find()) {
+			return Integer.parseInt(mat.group(1));
+		}
+
+		return 1;
+	}
 }

src/main/java/com/jozufozu/flywheel/core/compile/FragmentCompiler.java

@@ -4,9 +4,11 @@ import java.util.Objects;
 
 import com.jozufozu.flywheel.backend.gl.shader.GlShader;
 import com.jozufozu.flywheel.backend.gl.shader.ShaderType;
-import com.jozufozu.flywheel.backend.source.FileResolution;
+import com.jozufozu.flywheel.core.shader.ShaderConstants;
-import com.jozufozu.flywheel.backend.source.SourceFile;
 import com.jozufozu.flywheel.core.shader.StateSnapshot;
+import com.jozufozu.flywheel.core.source.FileIndexImpl;
+import com.jozufozu.flywheel.core.source.FileResolution;
+import com.jozufozu.flywheel.core.source.SourceFile;
 
 public class FragmentCompiler extends Memoizer<FragmentCompiler.Context, GlShader> {
 	private final FileResolution header;
@@ -43,9 +45,23 @@ public class FragmentCompiler extends Memoizer<FragmentCompiler.Context, GlShade
 		value.delete();
 	}
 
+	/**
+	 * Represents the conditions under which a shader is compiled.
+	 */
 	public static final class Context {
+		/**
+		 * The file to compile.
+		 */
 		private final SourceFile file;
+
+		/**
+		 * The shader constants to apply.
+		 */
 		private final StateSnapshot ctx;
+
+		/**
+		 * Alpha threshold below which fragments are discarded.
+		 */
 		private final float alphaDiscard;
 
 		public Context(SourceFile file, StateSnapshot ctx, float alphaDiscard) {

src/main/java/com/jozufozu/flywheel/core/compile/FragmentTemplateData.java

@@ -3,13 +3,13 @@ package com.jozufozu.flywheel.core.compile;
 import java.util.Optional;
 
 import com.google.common.collect.ImmutableList;
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.SourceFile;
-import com.jozufozu.flywheel.backend.source.error.ErrorReporter;
+import com.jozufozu.flywheel.core.source.error.ErrorReporter;
-import com.jozufozu.flywheel.backend.source.parse.ShaderFunction;
+import com.jozufozu.flywheel.core.source.parse.ShaderFunction;
-import com.jozufozu.flywheel.backend.source.parse.ShaderStruct;
+import com.jozufozu.flywheel.core.source.parse.ShaderStruct;
-import com.jozufozu.flywheel.backend.source.parse.StructField;
+import com.jozufozu.flywheel.core.source.parse.StructField;
-import com.jozufozu.flywheel.backend.source.parse.Variable;
+import com.jozufozu.flywheel.core.source.parse.Variable;
-import com.jozufozu.flywheel.backend.source.span.Span;
+import com.jozufozu.flywheel.core.source.span.Span;
 
 public class FragmentTemplateData implements FragmentData {
 	public final SourceFile file;

src/main/java/com/jozufozu/flywheel/core/compile/InstancingTemplateData.java

@@ -4,14 +4,15 @@ import java.util.Optional;
 
 import com.google.common.collect.ImmutableList;
 import com.jozufozu.flywheel.api.vertex.VertexType;
-import com.jozufozu.flywheel.backend.source.ShaderLoadingException;
+import com.jozufozu.flywheel.core.source.FileIndex;
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.ShaderLoadingException;
-import com.jozufozu.flywheel.backend.source.error.ErrorReporter;
+import com.jozufozu.flywheel.core.source.SourceFile;
-import com.jozufozu.flywheel.backend.source.parse.ShaderFunction;
+import com.jozufozu.flywheel.core.source.error.ErrorReporter;
-import com.jozufozu.flywheel.backend.source.parse.ShaderStruct;
+import com.jozufozu.flywheel.core.source.parse.ShaderFunction;
-import com.jozufozu.flywheel.backend.source.parse.StructField;
+import com.jozufozu.flywheel.core.source.parse.ShaderStruct;
-import com.jozufozu.flywheel.backend.source.parse.Variable;
+import com.jozufozu.flywheel.core.source.parse.StructField;
-import com.jozufozu.flywheel.backend.source.span.Span;
+import com.jozufozu.flywheel.core.source.parse.Variable;
+import com.jozufozu.flywheel.core.source.span.Span;
 
 public class InstancingTemplateData implements VertexData {
 
@@ -83,7 +84,7 @@ public class InstancingTemplateData implements VertexData {
 					.append("a_i_")
 					.append(field.name)
 					.append(";\n");
-			attributeBinding += TypeHelper.getAttributeCount(field.type);
+			attributeBinding += CompileUtil.getAttributeCount(field.type);
 		}
 		template.append(String.format("""
 						out vec4 v2f_color;

src/main/java/com/jozufozu/flywheel/core/compile/OneShotTemplateData.java

@@ -4,11 +4,12 @@ import java.util.Optional;
 
 import com.google.common.collect.ImmutableList;
 import com.jozufozu.flywheel.api.vertex.VertexType;
-import com.jozufozu.flywheel.backend.source.ShaderLoadingException;
+import com.jozufozu.flywheel.core.source.FileIndex;
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.ShaderLoadingException;
-import com.jozufozu.flywheel.backend.source.error.ErrorReporter;
+import com.jozufozu.flywheel.core.source.SourceFile;
-import com.jozufozu.flywheel.backend.source.parse.ShaderFunction;
+import com.jozufozu.flywheel.core.source.error.ErrorReporter;
-import com.jozufozu.flywheel.backend.source.parse.Variable;
+import com.jozufozu.flywheel.core.source.parse.ShaderFunction;
+import com.jozufozu.flywheel.core.source.parse.Variable;
 
 public class OneShotTemplateData implements VertexData {
 

src/main/java/com/jozufozu/flywheel/core/compile/ProgramCompiler.java

@@ -4,8 +4,8 @@ import java.util.ArrayList;
 import java.util.List;
 
 import com.jozufozu.flywheel.backend.gl.shader.GlProgram;
-import com.jozufozu.flywheel.backend.source.FileResolution;
 import com.jozufozu.flywheel.core.Templates;
+import com.jozufozu.flywheel.core.source.FileResolution;
 import com.jozufozu.flywheel.event.ReloadRenderersEvent;
 
 /**

src/main/java/com/jozufozu/flywheel/core/compile/ProgramContext.java

@@ -6,8 +6,8 @@ import javax.annotation.Nullable;
 
 import com.jozufozu.flywheel.api.vertex.VertexType;
 import com.jozufozu.flywheel.backend.Backend;
-import com.jozufozu.flywheel.backend.GameStateRegistry;
 import com.jozufozu.flywheel.backend.RenderLayer;
+import com.jozufozu.flywheel.core.GameStateRegistry;
 import com.jozufozu.flywheel.core.shader.ProgramSpec;
 import com.jozufozu.flywheel.core.shader.StateSnapshot;
 
@@ -15,7 +15,6 @@ import net.minecraft.resources.ResourceLocation;
 
 /**
  * Represents the entire context of a program's usage.
- *
  */
 public final class ProgramContext {
 	/**
@@ -27,8 +26,7 @@ public final class ProgramContext {
 	 * @return A compilation context.
 	 */
 	public static ProgramContext create(ResourceLocation programName, VertexType vertexType, @Nullable RenderLayer layer) {
-		ProgramSpec spec = Backend.getInstance()
+		ProgramSpec spec = Backend.getSpec(programName);
-				.getSpec(programName);
 
 		if (spec == null) {
 			throw new NullPointerException("Cannot compile shader because '" + programName + "' is not recognized.");

src/main/java/com/jozufozu/flywheel/core/compile/Template.java

@@ -1,11 +1,9 @@
 package com.jozufozu.flywheel.core.compile;
 
-import java.util.HashMap;
-import java.util.Map;
 import java.util.function.Function;
 
 import com.jozufozu.flywheel.backend.gl.GLSLVersion;
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.SourceFile;
 
 /**
  * A class that generates glsl glue code given a SourceFile.
@@ -15,9 +13,7 @@ import com.jozufozu.flywheel.backend.source.SourceFile;
  *     metadata to generate shader code that OpenGL can use to call into our shader programs.
  * </p>
  */
-public class Template<T> {
+public class Template<T> extends Memoizer<SourceFile, T> {
-
-	private final Map<SourceFile, T> metadata = new HashMap<>();
 
 	private final Function<SourceFile, T> reader;
 	private final GLSLVersion glslVersion;
@@ -34,7 +30,7 @@ public class Template<T> {
 	 */
 	public T apply(SourceFile file) {
 		// lazily read files, cache results
-		return metadata.computeIfAbsent(file, reader);
+		return super.get(file);
 	}
 
 	/**
@@ -44,4 +40,13 @@ public class Template<T> {
 		return glslVersion;
 	}
 
+	@Override
+	protected T _create(SourceFile key) {
+		return reader.apply(key);
+	}
+
+	@Override
+	protected void _destroy(T value) {
+		// noop
+	}
 }

src/main/java/com/jozufozu/flywheel/core/compile/TypeHelper.java

@@ -1,37 +0,0 @@
-package com.jozufozu.flywheel.core.compile;
-
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
-
-public class TypeHelper {
-
-	public static final Pattern vecType = Pattern.compile("^[biud]?vec([234])$");
-	public static final Pattern matType = Pattern.compile("^mat([234])(?:x([234]))?$");
-
-	public static int getElementCount(String type) {
-		Matcher vec = vecType.matcher(type);
-		if (vec.find()) return Integer.parseInt(vec.group(1));
-
-		Matcher mat = matType.matcher(type);
-		if (mat.find()) {
-			int n = Integer.parseInt(mat.group(1));
-
-			String m = mat.group(2);
-
-			if (m != null) return Integer.parseInt(m) * n;
-
-			return n;
-		}
-
-		return 1;
-	}
-
-	public static int getAttributeCount(CharSequence type) {
-		Matcher mat = matType.matcher(type);
-		if (mat.find()) {
-			return Integer.parseInt(mat.group(1));
-		}
-
-		return 1;
-	}
-}

src/main/java/com/jozufozu/flywheel/core/compile/VertexCompiler.java

@@ -5,9 +5,10 @@ import java.util.Objects;
 import com.jozufozu.flywheel.api.vertex.VertexType;
 import com.jozufozu.flywheel.backend.gl.shader.GlShader;
 import com.jozufozu.flywheel.backend.gl.shader.ShaderType;
-import com.jozufozu.flywheel.backend.source.FileResolution;
-import com.jozufozu.flywheel.backend.source.SourceFile;
 import com.jozufozu.flywheel.core.shader.StateSnapshot;
+import com.jozufozu.flywheel.core.source.FileIndexImpl;
+import com.jozufozu.flywheel.core.source.FileResolution;
+import com.jozufozu.flywheel.core.source.SourceFile;
 
 public class VertexCompiler extends Memoizer<VertexCompiler.Context, GlShader> {
 	private final Template<? extends VertexData> template;
@@ -55,8 +56,19 @@ public class VertexCompiler extends Memoizer<VertexCompiler.Context, GlShader> {
 	}
 
 	public static class Context {
+		/**
+		 * The file to compile.
+		 */
 		private final SourceFile file;
+
+		/**
+		 * The shader constants to apply.
+		 */
 		private final StateSnapshot ctx;
+
+		/**
+		 * The vertex type to use.
+		 */
 		private final VertexType vertexType;
 
 		public Context(SourceFile file, StateSnapshot ctx, VertexType vertexType) {

src/main/java/com/jozufozu/flywheel/core/compile/VertexData.java

@@ -1,6 +1,7 @@
 package com.jozufozu.flywheel.core.compile;
 
 import com.jozufozu.flywheel.api.vertex.VertexType;
+import com.jozufozu.flywheel.core.source.FileIndex;
 
 public interface VertexData {
 	/**

src/main/java/com/jozufozu/flywheel/core/shader/ExtensionInstance.java

@@ -1,13 +0,0 @@
-package com.jozufozu.flywheel.core.shader;
-
-import net.minecraft.resources.ResourceLocation;
-
-public interface ExtensionInstance {
-
-	/**
-	 * Bind the extra program state. It is recommended to grab the state information from global variables.
-	 */
-	void bind();
-
-	ResourceLocation name();
-}

src/main/java/com/jozufozu/flywheel/core/shader/GameStateProvider.java

@@ -1,7 +1,5 @@
 package com.jozufozu.flywheel.core.shader;
 
-import com.jozufozu.flywheel.core.compile.ShaderConstants;
-
 import net.minecraft.resources.ResourceLocation;
 
 public interface GameStateProvider {

src/main/java/com/jozufozu/flywheel/core/shader/NormalDebugStateProvider.java

@@ -2,7 +2,6 @@ package com.jozufozu.flywheel.core.shader;
 
 import com.jozufozu.flywheel.Flywheel;
 import com.jozufozu.flywheel.config.FlwConfig;
-import com.jozufozu.flywheel.core.compile.ShaderConstants;
 
 import net.minecraft.resources.ResourceLocation;
 

src/main/java/com/jozufozu/flywheel/core/shader/ProgramSpec.java

@@ -1,8 +1,8 @@
 package com.jozufozu.flywheel.core.shader;
 
-import com.jozufozu.flywheel.backend.source.FileResolution;
+import com.jozufozu.flywheel.core.source.FileResolution;
-import com.jozufozu.flywheel.backend.source.Resolver;
+import com.jozufozu.flywheel.core.source.Resolver;
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.SourceFile;
 import com.mojang.serialization.Codec;
 import com.mojang.serialization.codecs.RecordCodecBuilder;
 

src/main/java/com/jozufozu/flywheel/core/shader/ShaderConstants.java

@@ -1,12 +1,16 @@
-package com.jozufozu.flywheel.core.compile;
+package com.jozufozu.flywheel.core.shader;
 
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+/**
+ * A class for manipulating a list of {@code #define} directives.
+ *
+ * <p>Based loosely on code by jellysquid3.
+ */
 public class ShaderConstants {
 
-
 	private final Map<String, String> definitions = new HashMap<>();
 
 	public ShaderConstants define(String def) {

src/main/java/com/jozufozu/flywheel/core/shader/StateSnapshot.java

@@ -1,7 +1,6 @@
 package com.jozufozu.flywheel.core.shader;
 
-import com.jozufozu.flywheel.backend.GameStateRegistry;
+import com.jozufozu.flywheel.core.GameStateRegistry;
-import com.jozufozu.flywheel.core.compile.ShaderConstants;
 
 public record StateSnapshot(long ctx) {
 	// TODO: is this needed?

src/main/java/com/jozufozu/flywheel/core/shader/WorldFog.java

@@ -2,15 +2,10 @@ package com.jozufozu.flywheel.core.shader;
 
 import org.lwjgl.opengl.GL20;
 
-import com.jozufozu.flywheel.Flywheel;
 import com.jozufozu.flywheel.backend.gl.shader.GlProgram;
 import com.mojang.blaze3d.systems.RenderSystem;
 
-import net.minecraft.resources.ResourceLocation;
+public class WorldFog {
-
-public class WorldFog implements ExtensionInstance {
-
-	public static final ResourceLocation NAME = Flywheel.rl("fog");
 
 	private final int uFogColor;
 	private final int uFogRange;
@@ -20,14 +15,8 @@ public class WorldFog implements ExtensionInstance {
 		this.uFogRange = program.getUniformLocation("uFogRange");
 	}
 
-	@Override
 	public void bind() {
 		GL20.glUniform2f(uFogRange, RenderSystem.getShaderFogStart(), RenderSystem.getShaderFogEnd());
 		GL20.glUniform4fv(uFogColor, RenderSystem.getShaderFogColor());
 	}
-
-	@Override
-	public ResourceLocation name() {
-		return NAME;
-	}
 }

src/main/java/com/jozufozu/flywheel/core/source/FileIndex.java

@@ -1,7 +1,6 @@
-package com.jozufozu.flywheel.core.compile;
+package com.jozufozu.flywheel.core.source;
 
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.span.Span;
-import com.jozufozu.flywheel.backend.source.span.Span;
 
 public interface FileIndex {
 	/**

src/main/java/com/jozufozu/flywheel/core/source/FileIndexImpl.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.core.compile;
+package com.jozufozu.flywheel.core.source;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -6,9 +6,8 @@ import java.util.List;
 import javax.annotation.Nullable;
 
 import com.jozufozu.flywheel.backend.Backend;
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.error.ErrorBuilder;
-import com.jozufozu.flywheel.backend.source.error.ErrorBuilder;
+import com.jozufozu.flywheel.core.source.error.ErrorReporter;
-import com.jozufozu.flywheel.backend.source.error.ErrorReporter;
 
 import net.minecraft.resources.ResourceLocation;
 

src/main/java/com/jozufozu/flywheel/core/source/FileResolution.java

@@ -1,12 +1,12 @@
-package com.jozufozu.flywheel.backend.source;
+package com.jozufozu.flywheel.core.source;
 
 import java.util.ArrayList;
 import java.util.List;
 import java.util.function.Consumer;
 
 import com.jozufozu.flywheel.backend.Backend;
-import com.jozufozu.flywheel.backend.source.error.ErrorBuilder;
+import com.jozufozu.flywheel.core.source.error.ErrorBuilder;
-import com.jozufozu.flywheel.backend.source.span.Span;
+import com.jozufozu.flywheel.core.source.span.Span;
 
 import net.minecraft.resources.ResourceLocation;
 

src/main/java/com/jozufozu/flywheel/core/source/Index.java

@@ -1,12 +1,12 @@
-package com.jozufozu.flywheel.backend.source;
+package com.jozufozu.flywheel.core.source;
 
 import java.util.Collection;
 import java.util.Map;
 
 import com.google.common.collect.Multimap;
 import com.google.common.collect.MultimapBuilder;
-import com.jozufozu.flywheel.backend.source.parse.ShaderFunction;
+import com.jozufozu.flywheel.core.source.parse.ShaderFunction;
-import com.jozufozu.flywheel.backend.source.parse.ShaderStruct;
+import com.jozufozu.flywheel.core.source.parse.ShaderStruct;
 
 import net.minecraft.resources.ResourceLocation;
 

src/main/java/com/jozufozu/flywheel/core/source/Resolver.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source;
+package com.jozufozu.flywheel.core.source;
 
 import java.util.HashMap;
 import java.util.Map;

src/main/java/com/jozufozu/flywheel/core/source/ShaderLoadingException.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source;
+package com.jozufozu.flywheel.core.source;
 
 public class ShaderLoadingException extends RuntimeException {
 

src/main/java/com/jozufozu/flywheel/core/source/ShaderSources.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source;
+package com.jozufozu.flywheel.core.source;
 
 import java.io.IOException;
 import java.util.ArrayList;

src/main/java/com/jozufozu/flywheel/core/source/SourceFile.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source;
+package com.jozufozu.flywheel.core.source;
 
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -10,13 +10,12 @@ import java.util.regex.Pattern;
 
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
-import com.jozufozu.flywheel.backend.source.parse.Import;
+import com.jozufozu.flywheel.core.source.parse.Import;
-import com.jozufozu.flywheel.backend.source.parse.ShaderFunction;
+import com.jozufozu.flywheel.core.source.parse.ShaderFunction;
-import com.jozufozu.flywheel.backend.source.parse.ShaderStruct;
+import com.jozufozu.flywheel.core.source.parse.ShaderStruct;
-import com.jozufozu.flywheel.backend.source.span.ErrorSpan;
+import com.jozufozu.flywheel.core.source.span.ErrorSpan;
-import com.jozufozu.flywheel.backend.source.span.Span;
+import com.jozufozu.flywheel.core.source.span.Span;
-import com.jozufozu.flywheel.backend.source.span.StringSpan;
+import com.jozufozu.flywheel.core.source.span.StringSpan;
-import com.jozufozu.flywheel.core.compile.FileIndex;
 
 import net.minecraft.resources.ResourceLocation;
 

src/main/java/com/jozufozu/flywheel/core/source/SourceFinder.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source;
+package com.jozufozu.flywheel.core.source;
 
 import javax.annotation.Nullable;
 

src/main/java/com/jozufozu/flywheel/core/source/SourceLines.java

@@ -1,10 +1,10 @@
-package com.jozufozu.flywheel.backend.source;
+package com.jozufozu.flywheel.core.source;
 
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 import com.google.common.collect.ImmutableList;
-import com.jozufozu.flywheel.backend.source.span.CharPos;
+import com.jozufozu.flywheel.core.source.span.CharPos;
 import com.jozufozu.flywheel.util.StringUtil;
 
 import it.unimi.dsi.fastutil.ints.IntArrayList;

src/main/java/com/jozufozu/flywheel/core/source/error/ErrorBuilder.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source.error;
+package com.jozufozu.flywheel.core.source.error;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -7,16 +7,16 @@ import java.util.regex.Pattern;
 
 import javax.annotation.Nullable;
 
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.FileIndex;
-import com.jozufozu.flywheel.backend.source.SourceLines;
+import com.jozufozu.flywheel.core.source.SourceFile;
-import com.jozufozu.flywheel.backend.source.error.lines.ErrorLine;
+import com.jozufozu.flywheel.core.source.SourceLines;
-import com.jozufozu.flywheel.backend.source.error.lines.FileLine;
+import com.jozufozu.flywheel.core.source.error.lines.ErrorLine;
-import com.jozufozu.flywheel.backend.source.error.lines.HeaderLine;
+import com.jozufozu.flywheel.core.source.error.lines.FileLine;
-import com.jozufozu.flywheel.backend.source.error.lines.SourceLine;
+import com.jozufozu.flywheel.core.source.error.lines.HeaderLine;
-import com.jozufozu.flywheel.backend.source.error.lines.SpanHighlightLine;
+import com.jozufozu.flywheel.core.source.error.lines.SourceLine;
-import com.jozufozu.flywheel.backend.source.error.lines.TextLine;
+import com.jozufozu.flywheel.core.source.error.lines.SpanHighlightLine;
-import com.jozufozu.flywheel.backend.source.span.Span;
+import com.jozufozu.flywheel.core.source.error.lines.TextLine;
-import com.jozufozu.flywheel.core.compile.FileIndex;
+import com.jozufozu.flywheel.core.source.span.Span;
 import com.jozufozu.flywheel.util.FlwUtil;
 
 public class ErrorBuilder {

src/main/java/com/jozufozu/flywheel/core/source/error/ErrorLevel.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source.error;
+package com.jozufozu.flywheel.core.source.error;
 
 public enum ErrorLevel {
 	WARN("warn"),

src/main/java/com/jozufozu/flywheel/core/source/error/ErrorReporter.java

@@ -1,14 +1,14 @@
-package com.jozufozu.flywheel.backend.source.error;
+package com.jozufozu.flywheel.core.source.error;
 
 import java.util.List;
 import java.util.Optional;
 
 import com.jozufozu.flywheel.Flywheel;
 import com.jozufozu.flywheel.backend.Backend;
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.SourceFile;
-import com.jozufozu.flywheel.backend.source.parse.ShaderFunction;
+import com.jozufozu.flywheel.core.source.parse.ShaderFunction;
-import com.jozufozu.flywheel.backend.source.parse.ShaderStruct;
+import com.jozufozu.flywheel.core.source.parse.ShaderStruct;
-import com.jozufozu.flywheel.backend.source.span.Span;
+import com.jozufozu.flywheel.core.source.span.Span;
 import com.jozufozu.flywheel.util.FlwUtil;
 
 public class ErrorReporter {

src/main/java/com/jozufozu/flywheel/core/source/error/lines/Divider.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source.error.lines;
+package com.jozufozu.flywheel.core.source.error.lines;
 
 public enum Divider {
 	BAR(" | "),

src/main/java/com/jozufozu/flywheel/core/source/error/lines/ErrorLine.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source.error.lines;
+package com.jozufozu.flywheel.core.source.error.lines;
 
 public interface ErrorLine {
 

src/main/java/com/jozufozu/flywheel/core/source/error/lines/FileLine.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source.error.lines;
+package com.jozufozu.flywheel.core.source.error.lines;
 
 public record FileLine(String fileName) implements ErrorLine {
 

src/main/java/com/jozufozu/flywheel/core/source/error/lines/HeaderLine.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source.error.lines;
+package com.jozufozu.flywheel.core.source.error.lines;
 
 public record HeaderLine(String level, CharSequence message) implements ErrorLine {
 

src/main/java/com/jozufozu/flywheel/core/source/error/lines/SourceLine.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source.error.lines;
+package com.jozufozu.flywheel.core.source.error.lines;
 
 public record SourceLine(String number, String line) implements ErrorLine {
 

src/main/java/com/jozufozu/flywheel/core/source/error/lines/SpanHighlightLine.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source.error.lines;
+package com.jozufozu.flywheel.core.source.error.lines;
 
 public class SpanHighlightLine implements ErrorLine {
 	private final String line;

src/main/java/com/jozufozu/flywheel/core/source/error/lines/TextLine.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source.error.lines;
+package com.jozufozu.flywheel.core.source.error.lines;
 
 public record TextLine(String msg) implements ErrorLine {
 

src/main/java/com/jozufozu/flywheel/core/source/error/package-info.java

@@ -1,5 +1,5 @@
 @ParametersAreNonnullByDefault @MethodsReturnNonnullByDefault
-package com.jozufozu.flywheel.backend.source.span;
+package com.jozufozu.flywheel.core.source.error;
 
 import javax.annotation.ParametersAreNonnullByDefault;
 

src/main/java/com/jozufozu/flywheel/core/source/package-info.java

@@ -1,5 +1,5 @@
 @ParametersAreNonnullByDefault @MethodsReturnNonnullByDefault
-package com.jozufozu.flywheel.backend.source;
+package com.jozufozu.flywheel.core.source;
 
 import javax.annotation.ParametersAreNonnullByDefault;
 

src/main/java/com/jozufozu/flywheel/core/source/parse/AbstractShaderElement.java

@@ -1,6 +1,6 @@
-package com.jozufozu.flywheel.backend.source.parse;
+package com.jozufozu.flywheel.core.source.parse;
 
-import com.jozufozu.flywheel.backend.source.span.Span;
+import com.jozufozu.flywheel.core.source.span.Span;
 
 public abstract class AbstractShaderElement {
 

src/main/java/com/jozufozu/flywheel/core/source/parse/Import.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source.parse;
+package com.jozufozu.flywheel.core.source.parse;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -6,11 +6,11 @@ import java.util.Optional;
 
 import javax.annotation.Nullable;
 
-import com.jozufozu.flywheel.backend.source.FileResolution;
+import com.jozufozu.flywheel.core.source.FileResolution;
-import com.jozufozu.flywheel.backend.source.Resolver;
+import com.jozufozu.flywheel.core.source.Resolver;
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.SourceFile;
-import com.jozufozu.flywheel.backend.source.error.ErrorReporter;
+import com.jozufozu.flywheel.core.source.error.ErrorReporter;
-import com.jozufozu.flywheel.backend.source.span.Span;
+import com.jozufozu.flywheel.core.source.span.Span;
 
 import net.minecraft.resources.ResourceLocation;
 

src/main/java/com/jozufozu/flywheel/core/source/parse/ShaderFunction.java

@@ -1,11 +1,11 @@
-package com.jozufozu.flywheel.backend.source.parse;
+package com.jozufozu.flywheel.core.source.parse;
 
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 
 import com.google.common.collect.ImmutableList;
-import com.jozufozu.flywheel.backend.source.span.Span;
+import com.jozufozu.flywheel.core.source.span.Span;
 
 public class ShaderFunction extends AbstractShaderElement {
 

src/main/java/com/jozufozu/flywheel/core/source/parse/ShaderStruct.java

@@ -1,11 +1,11 @@
-package com.jozufozu.flywheel.backend.source.parse;
+package com.jozufozu.flywheel.core.source.parse;
 
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
-import com.jozufozu.flywheel.backend.source.span.Span;
+import com.jozufozu.flywheel.core.source.span.Span;
 
 public class ShaderStruct extends AbstractShaderElement {
 

src/main/java/com/jozufozu/flywheel/core/source/parse/StructField.java

@@ -1,8 +1,8 @@
-package com.jozufozu.flywheel.backend.source.parse;
+package com.jozufozu.flywheel.core.source.parse;
 
 import java.util.regex.Pattern;
 
-import com.jozufozu.flywheel.backend.source.span.Span;
+import com.jozufozu.flywheel.core.source.span.Span;
 
 public class StructField extends AbstractShaderElement {
 	public static final Pattern fieldPattern = Pattern.compile("(\\S+)\\s*(\\S+);");

src/main/java/com/jozufozu/flywheel/core/source/parse/Variable.java

@@ -1,6 +1,6 @@
-package com.jozufozu.flywheel.backend.source.parse;
+package com.jozufozu.flywheel.core.source.parse;
 
-import com.jozufozu.flywheel.backend.source.span.Span;
+import com.jozufozu.flywheel.core.source.span.Span;
 
 public class Variable extends AbstractShaderElement {
 

src/main/java/com/jozufozu/flywheel/core/source/parse/package-info.java

@@ -1,6 +1,6 @@
 @ParametersAreNonnullByDefault
 @MethodsReturnNonnullByDefault
-package com.jozufozu.flywheel.backend.source.parse;
+package com.jozufozu.flywheel.core.source.parse;
 
 import javax.annotation.ParametersAreNonnullByDefault;
 

src/main/java/com/jozufozu/flywheel/core/source/span/CharPos.java

@@ -1,4 +1,4 @@
-package com.jozufozu.flywheel.backend.source.span;
+package com.jozufozu.flywheel.core.source.span;
 
 /**
  * A position in a file.

src/main/java/com/jozufozu/flywheel/core/source/span/ErrorSpan.java

@@ -1,6 +1,6 @@
-package com.jozufozu.flywheel.backend.source.span;
+package com.jozufozu.flywheel.core.source.span;
 
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.SourceFile;
 
 /**
  * Represents a (syntactically) malformed segment of code.

src/main/java/com/jozufozu/flywheel/core/source/span/Span.java

@@ -1,8 +1,8 @@
-package com.jozufozu.flywheel.backend.source.span;
+package com.jozufozu.flywheel.core.source.span;
 
 import java.util.regex.Matcher;
 
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.SourceFile;
 
 /**
  * A segment of code in a {@link SourceFile}.

src/main/java/com/jozufozu/flywheel/core/source/span/StringSpan.java

@@ -1,6 +1,6 @@
-package com.jozufozu.flywheel.backend.source.span;
+package com.jozufozu.flywheel.core.source.span;
 
-import com.jozufozu.flywheel.backend.source.SourceFile;
+import com.jozufozu.flywheel.core.source.SourceFile;
 
 public class StringSpan extends Span {
 

src/main/java/com/jozufozu/flywheel/core/source/span/package-info.java

@@ -1,5 +1,5 @@
 @ParametersAreNonnullByDefault @MethodsReturnNonnullByDefault
-package com.jozufozu.flywheel.backend.source.error;
+package com.jozufozu.flywheel.core.source.span;
 
 import javax.annotation.ParametersAreNonnullByDefault;
 

src/main/java/com/jozufozu/flywheel/event/ForgeEvents.java

@@ -24,8 +24,7 @@ public class ForgeEvents {
 
 			ArrayList<String> right = event.getRight();
 
-			String text = "Flywheel: " + Backend.getInstance()
+			String text = "Flywheel: " + Backend.getBackendDescriptor();
-					.getBackendDescriptor();
 			if (right.size() < 10) {
 				right.add("");
 				right.add(text);

src/main/java/com/jozufozu/flywheel/event/GatherContextEvent.java

@@ -1,24 +1,16 @@
 package com.jozufozu.flywheel.event;
 
-import com.jozufozu.flywheel.backend.Backend;
-
 import net.minecraftforge.eventbus.api.Event;
 import net.minecraftforge.fml.event.IModBusEvent;
 
 public class GatherContextEvent extends Event implements IModBusEvent {
 
-	private final Backend backend;
 	private final boolean firstLoad;
 
-	public GatherContextEvent(Backend backend, boolean firstLoad) {
+	public GatherContextEvent(boolean firstLoad) {
-		this.backend = backend;
 		this.firstLoad = firstLoad;
 	}
 
-	public Backend getBackend() {
-		return backend;
-	}
-
 	/**
 	 * @return true iff it is the first time the event is fired.
 	 */

src/main/java/com/jozufozu/flywheel/mixin/LevelRendererMixin.java

@@ -67,8 +67,7 @@ public class LevelRendererMixin {
 
 	@Inject(at = @At("TAIL"), method = "allChanged")
 	private void refresh(CallbackInfo ci) {
-		Backend.getInstance()
+		Backend.refresh();
-				.refresh();
 
 		MinecraftForge.EVENT_BUS.post(new ReloadRenderersEvent(level));
 	}