Update to newer gaemstone.ECS and Flecs

- Allow specifying just [Path] for entity, making it built-in
- Built-in entities error if the entity doesn't already exist

src/Immersion/Program.cs

@@ -23,8 +23,8 @@ var universe = new Universe<Program>();
 var world    = universe.World;
 
 // TODO: Figure out a nice way to get rid of "compile errors" here.
+// FIXME: universe.Modules.Register<gaemstone.Flecs.Systems.Monitor>();
 universe.Modules.Register<gaemstone.Flecs.Systems.Rest>();
-universe.Modules.Register<gaemstone.Flecs.Systems.Monitor>();
 
 var window = Window.Create(WindowOptions.Default with {
 	Title = "gæmstone",
@@ -34,8 +34,8 @@ var window = Window.Create(WindowOptions.Default with {
 window.Initialize();
 window.Center();
 
-// universe.Modules.Register<ObserverTest>();
-// universe.Modules.Register<ManagedComponentTest>();
+// universe.Modules.Register<Immersion.ObserverTest>();
+// universe.Modules.Register<Immersion.ManagedComponentTest>();
 
 universe.Modules.Register<gaemstone.Client.Systems.Windowing>();
 universe.Modules.Register<gaemstone.Components.TransformComponents>();

src/gaemstone.Client/Systems/InputManager.cs

@@ -109,11 +109,18 @@ public partial class InputManager
 	{
 		entity.GetMut<RawValue1D>() = current;
 		if (current >= ActivationThreshold) {
-			ref var active = ref entity.GetRefOrNull<Active>();
-			if (Unsafe.IsNullRef(ref active)) {
+			// TODO: Find out why using GetRefOrNull here crashes.
+			if (entity.Has<Active>()) {
+				entity.GetMut<Active>().Duration += delta;
+			} else {
 				entity.Set(new Active());
 				entity.Add<Activated>();
-			} else active.Duration += delta;
+			}
+			// ref var active = ref entity.GetRefOrNull<Active>();
+			// if (Unsafe.IsNullRef(ref active)) {
+			// 	entity.Set(new Active());
+			// 	entity.Add<Activated>();
+			// } else active.Duration += delta;
 		} else if (current <= DeactivationThreshold)
 			entity.Remove<Active>();
 	}
@@ -123,11 +130,17 @@ public partial class InputManager
 		entity.GetMut<RawValue2D>() = current;
 		var magnitude = current.Length();
 		if (magnitude >= ActivationThreshold) {
-			ref var active = ref entity.GetRefOrNull<Active>();
-			if (Unsafe.IsNullRef(ref active)) {
+			if (entity.Has<Active>()) {
+				entity.GetMut<Active>().Duration += delta;
+			} else {
 				entity.Set(new Active());
 				entity.Add<Activated>();
-			} else active.Duration += delta;
+			}
+			// ref var active = ref entity.GetRefOrNull<Active>();
+			// if (Unsafe.IsNullRef(ref active)) {
+			// 	entity.Set(new Active());
+			// 	entity.Add<Activated>();
+			// } else active.Duration += delta;
 		} else if (magnitude <= DeactivationThreshold)
 			entity.Remove<Active>();
 	}
@@ -138,12 +151,12 @@ public partial class InputManager
 	// public static void OnActiveAdded(EntityRef entity, Active _)
 	// 	=> entity.Add<Activated>();
 
-	[Observer<Core.OnRemove>]
-	public static void OnActiveRemoved<T>(Entity<T> entity, Active _)
-		=> entity.Add<Deactivated>();
+	// [Observer<Core.OnRemove>]
+	// public static void OnActiveRemoved<T>(Entity<T> entity, Active _)
+	// 	=> entity.Add<Deactivated>();
 
-	[System]
-	[DependsOn<Pipeline.PostFrame>]
-	public static void ClearDeActivated<T>(Entity<T> entity, Has<Or<Activated, Deactivated>> _)
-		=> entity.Remove<Activated>().Remove<Deactivated>();
+	// [System]
+	// [DependsOn<Pipeline.PostFrame>]
+	// public static void ClearDeActivated<T>(Entity<T> entity, Has<Or<Activated, Deactivated>> _)
+	// 	=> entity.Remove<Activated>().Remove<Deactivated>();
 }

src/gaemstone.ECS

@@ -1 +1 @@
-Subproject commit 9eade0adb1200223dffcb2077ecbc992569f4080
+Subproject commit eec968d6361930eebad180f6300d126c4bac70f3

src/gaemstone.SourceGen/Descriptors.cs

@@ -36,6 +36,12 @@ public static class Descriptors
 
 	// Diagnostics relating to the combined usage of attributes.
 
+	public static readonly DiagnosticDescriptor AttributesRequireTypeOrPath = new(
+		$"gSG{_idCounter++:00}", "Entity attributes require type or path",
+		"Entity attributes require a type (such as [Entity]) or [Path].",
+		DiagnosticCategory, DiagnosticSeverity.Error, true);
+
+
 	public static readonly DiagnosticDescriptor InvalidAttributeCombination = new(
 		$"gSG{_idCounter++:00}", "Invalid combination of entity attributes",
 		"The combination of entity attributes {0} is not valid.",
@@ -61,7 +67,10 @@ public static class Descriptors
 		"A [BuiltIn, Module] must also have a [Path] set.",
 		DiagnosticCategory, DiagnosticSeverity.Info, true);
 
-
+	public static readonly DiagnosticDescriptor BuiltInModuleMustNotHaveMethods = new(
+		$"gSG{_idCounter++:00}", "BuiltIn Module must not have System / Observer",
+		"A [BuiltIn, Module] must not have [System] or [Observer] methods.",
+		DiagnosticCategory, DiagnosticSeverity.Info, true);
 
 
 	// Diagnostics relating to keywords / modifiers used with the symbol.
@@ -182,6 +191,7 @@ public static class Descriptors
 		DiagnosticCategory, DiagnosticSeverity.Error, true);
 
 
+	// TODO: Make this more descriptive. (Special = Has<>, Not<> and [Tag]?)
 	public static readonly DiagnosticDescriptor SpecialMustNotBeByRef = new(
 		$"gSG{_idCounter++:00}", "Special parameter must not be ByRef",
 		"Special parameter must not be ByRef (in/out/ref).",

src/gaemstone.SourceGen/ModuleGenerator.cs

@@ -5,6 +5,7 @@ using System.Text;
 using gaemstone.SourceGen.Structure;
 using gaemstone.SourceGen.Utility;
 using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
 
 namespace gaemstone.SourceGen;
 
@@ -106,6 +107,7 @@ public class ModuleGenerator
 
 			""");
 
+		// TODO: Built-in modules should not have dependencies.
 		var dependencies = module.GetDependencies().ToList();
 		sb.Append("\tstatic IReadOnlyList<string> IModule.Dependencies { get; } = ");
 		if (dependencies.Count > 0) {
@@ -132,6 +134,9 @@ public class ModuleGenerator
 
 		// TODO: Can BuiltIn modules have systems and such?
 
+		if (module.HasInitializer)
+			sb.AppendLine("\t\tInitialize(module);");
+
 		sb.AppendLine("\t}");
 
 		sb.AppendLine("}");
@@ -151,26 +156,30 @@ public class ModuleGenerator
 		foreach (var e in entities) {
 			var @var = $"_{e.Name}_Entity";
 			var path = (e.EntityPath ?? e.Name).ToStringLiteral();
-			sb.AppendLine($"\t\tvar {@var} = world.New({path}, module)");
-			if (e.EntitySymbol != null)
-				sb.AppendLine($"\t\t\t.Symbol({e.EntitySymbol.ToStringLiteral()})");
+
+			// When looking for a BuiltIn entity, error if it doesn't exist.
+			var lookupFunc = (e.IsBuiltIn ? "LookupPathOrThrow" : "New");
+			sb.AppendLine($"\t\tvar {@var} = world.{lookupFunc}({path}, module)");
 
 			// Since this is a custom gaemstone tag, we want to add it even for [BuiltIn] modules.
 			if (e.IsRelation) sb.AppendLine("\t\t\t.Add<gaemstone.Doc.Relation>()");
 
+			// Other than [Relation], we don't add anything to entities defined in [BuiltIn] modules.
 			if (module.IsBuiltIn)
 			{
-				sb.AppendLine($"\t\t\t.Build().CreateLookup<{e.FullName}>()");
+				sb.AppendLine($"\t\t\t.CreateLookup<{e.FullName}>()");
 			}
 			else
 			{
-				// TODO: if (e.IsPublic) sb.AppendLine($"\t\t\t.Symbol(\"{e.Name}\")");
+				if (e.EntitySymbol != null)
+					sb.AppendLine($"\t\t\t.Symbol({e.EntitySymbol.ToStringLiteral()})");
 
 				// Tags and relations in Flecs are marked as empty components.
 				if (e.IsTag || e.IsRelation) sb.AppendLine("\t\t\t.Add<gaemstone.Flecs.Core.Component>()");
 				if (e.IsTag && e.IsRelation) sb.AppendLine("\t\t\t.Add<gaemstone.Flecs.Core.Tag>()");
 
-				                   sb.Append( "\t\t\t.Build()");
+				                   sb.Append( "\t\t\t");
+				if (!e.IsBuiltIn)  sb.Append(".Build()");
 				if (e.IsComponent) sb.Append($".InitComponent<{e.FullName}>()");
 				else               sb.Append($".CreateLookup<{e.FullName}>()");
 				                   sb.AppendLine();
@@ -289,6 +298,8 @@ public class ModuleGenerator
 				sb.AppendLine($"\t\t{@var}.Add<{a.GetFullName()}>();");
 			foreach (var (r, t) in e.RelationsToAdd)
 				sb.AppendLine($"\t\t{@var}.Add<{r.GetFullName()}, {t.GetFullName()}>();");
+			foreach (var (c, args) in e.ComponentsToAdd)
+				sb.AppendLine($"\t\t{@var}.Set(new {c.GetFullName()}({string.Join(", ", args.Select(a => a.ToCSharpString()))}));");
 
 			// If system doesn't have an explicit phase set, default to OnUpdate.
 			if (e is MethodEntityInfo { IsSystem: true, HasPhaseSet: false })

src/gaemstone.SourceGen/RelevantSymbolReceiver.cs

@@ -24,9 +24,10 @@ public class RelevantSymbolReceiver
 		"Observer",
 
 		// Entity properties that specify additional info / behavior
-		"Path",
+		"Path", // TODO: When referring to a pre-existing entity, only [Path] should be necessary, right?
 		"Symbol",
 		"Add",
+		"Set",
 		"BuiltIn",    // Valid on [Module]
 		"Expression", // Valid on [System] and [Observer]
 

src/gaemstone.SourceGen/Structure/BaseEntityInfo.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
 using System.Linq;
 using Microsoft.CodeAnalysis;
 
@@ -14,7 +15,11 @@ public abstract class BaseEntityInfo : BaseInfo
 
 	public List<INamedTypeSymbol> EntitiesToAdd { get; } = new();
 	public List<(INamedTypeSymbol Relation, INamedTypeSymbol Target)> RelationsToAdd { get; } = new();
-	public virtual bool HasEntitiesToAdd => (EntitiesToAdd.Count > 0) || (RelationsToAdd.Count > 0);
+	public List<(INamedTypeSymbol Component, ImmutableArray<TypedConstant> Arguments)> ComponentsToAdd { get; } = new();
+
+	public virtual bool HasEntitiesToAdd => (EntitiesToAdd.Count > 0)
+	                                     || (RelationsToAdd.Count > 0)
+	                                     || (ComponentsToAdd.Count > 0);
 
 	public BaseEntityInfo(ISymbol symbol)
 		: base(symbol)
@@ -41,33 +46,49 @@ public abstract class BaseEntityInfo : BaseInfo
 				Descriptors.EntityMustBeInModule, Location);
 		}
 
-		// Add entities and relationships specified using [Add<...>] attributes.
 		foreach (var attr in Symbol.GetAttributes()) {
+			// Add entities and relationships specified using [Add<...>] attributes.
 			for (var attrType = attr.AttributeClass; attrType != null; attrType = attrType.BaseType) {
-				if (RelevantSymbolReceiver.ToRelevantAttributeName(attrType) != "Add") continue;
+				var attrName = RelevantSymbolReceiver.ToRelevantAttributeName(attrType);
+				if (attrName is "Add" or "Set") {
 
-				var allTypeArgumentsValid = true;
-				for (var i = 0; i < attrType.TypeArguments.Length; i++) {
-					var arg   = attrType.TypeArguments[i];
-					var param = attrType.TypeParameters[i];
-					if (arg is not INamedTypeSymbol) {
-						yield return Diagnostic.Create(
-							Descriptors.InvalidTypeArgument, param.Locations.Single());
-						allTypeArgumentsValid = false;
+					var allTypeArgumentsValid = true;
+					for (var i = 0; i < attrType.TypeArguments.Length; i++) {
+						var arg   = attrType.TypeArguments[i];
+						var param = attrType.TypeParameters[i];
+						if (arg is not INamedTypeSymbol) {
+							yield return Diagnostic.Create(
+								Descriptors.InvalidTypeArgument, param.Locations.Single());
+							allTypeArgumentsValid = false;
+						}
+						// TODO: Make sure entities being added have appropriate attributes as well.
 					}
-					// TODO: Make sure entities being added have appropriate attributes as well.
-				}
+					if (!allTypeArgumentsValid) continue;
 
-				if (allTypeArgumentsValid) {
-					switch (attrType.TypeArguments) {
-						case [ INamedTypeSymbol entity ]:
-							EntitiesToAdd.Add(entity);
+					switch (attrName) {
+						case "Add":
+							switch (attrType.TypeArguments) {
+								case [ INamedTypeSymbol entity ]:
+									EntitiesToAdd.Add(entity);
+									break;
+								case [ INamedTypeSymbol relation, INamedTypeSymbol target ]:
+									RelationsToAdd.Add((relation, target));
+									break;
+								default: throw new InvalidOperationException(
+									"Type argument pattern matching failed");
+							}
 							break;
-						case [ INamedTypeSymbol relation, INamedTypeSymbol target ]:
-							RelationsToAdd.Add((relation, target));
+
+						case "Set":
+							var component = (INamedTypeSymbol)attrType.TypeArguments.Single();
+							var arguments = attr.ConstructorArguments.Single().Values;
+							// TODO: Verify arguments actually match a constructor.
+							// Right now this will just error in the generated code. Probably good enough?
+							ComponentsToAdd.Add((component, arguments));
 							break;
+
 						default: throw new InvalidOperationException(
-							"Type argument pattern matching failed");
+							"Invalid relevant attribute name");
 					}
 				}
 			}

src/gaemstone.SourceGen/Structure/MethodEntityInfo.cs

@@ -25,6 +25,8 @@ public class MethodEntityInfo : BaseEntityInfo
 	public bool HasPhaseSet { get; private set; }
 	public override bool HasEntitiesToAdd => base.HasEntitiesToAdd || !HasPhaseSet;
 
+	// TODO: Support [Source].
+
 	public MethodEntityInfo(ISymbol symbol)
 		: base(symbol)
 	{
@@ -43,6 +45,9 @@ public class MethodEntityInfo : BaseEntityInfo
 		if (IsSystem && IsObserver) yield return Diagnostic.Create(
 			Descriptors.InvalidAttributeCombination, Location, "[System, Observer]");
 
+		if (Parent is ModuleEntityInfo { IsBuiltIn: true }) yield return Diagnostic.Create(
+			Descriptors.BuiltInModuleMustNotHaveMethods, Location);
+
 		if (Symbol.IsAbstract) yield return Diagnostic.Create(
 			Descriptors.MethodMustNotBeAbstract, Location);
 		if (Symbol.IsAsync) yield return Diagnostic.Create(

src/gaemstone.SourceGen/Structure/ModuleEntityInfo.cs

@@ -10,15 +10,17 @@ namespace gaemstone.SourceGen.Structure;
 public class ModuleEntityInfo : TypeEntityInfo
 {
 	public bool IsPartial { get; }
-	public bool IsBuiltIn { get; }
-
-	// TODO: Support [Source].
+	public bool HasInitializer { get; }
 
 	public ModuleEntityInfo(ISymbol symbol)
 		: base(symbol)
 	{
 		var classDecl = (TypeDeclarationSyntax)Symbol.DeclaringSyntaxReferences.First().GetSyntax();
 		IsPartial = classDecl.Modifiers.Any(t => t.IsKind(SyntaxKind.PartialKeyword));
+
+		HasInitializer = Symbol.AllInterfaces.Any(i =>
+			i.GetFullName(FullNameStyle.NoGeneric) == "gaemstone.ECS.IModuleInitializer");
+
 		IsBuiltIn = Has("BuiltIn");
 	}
 

src/gaemstone.SourceGen/Structure/TypeEntityInfo.cs

@@ -17,6 +17,11 @@ public class TypeEntityInfo : BaseEntityInfo
 	public bool IsSingleton { get; }
 	public bool IsRelation { get; }
 
+	// Built-in entities error if they don't exist.
+	// When a module is built-in, most attributes become descriptive,
+	// and don't change or affect the entity they're attached to.
+	public bool IsBuiltIn { get; protected set; }
+
 	public bool IsValueType     => Symbol.IsValueType;
 	public bool IsReferenceType => Symbol.IsReferenceType;
 	// TODO: Make sure that component has (instance) fields, non-component entity does not have fields.
@@ -30,6 +35,10 @@ public class TypeEntityInfo : BaseEntityInfo
 		IsComponent = Has("Component");
 		IsSingleton = Has("Singleton");
 		IsRelation  = Has("Relation");
+
+		IsBuiltIn = !IsModule && !IsEntity && !IsTag
+				 && !IsComponent && !IsSingleton && !IsRelation
+				 && (EntityPath != null);
 	}
 
 	protected override IEnumerable<Diagnostic> ValidateSelf()
@@ -49,7 +58,14 @@ public class TypeEntityInfo : BaseEntityInfo
 		if (IsComponent) attributeList.Add("Component");
 		if (IsSingleton) attributeList.Add("Singleton");
 
-		switch (attributeList) {
+		switch (attributeList)
+		{
+			// No attributes are only valid if [Path] is set.
+			case [  ]:
+				if (!IsBuiltIn) yield return Diagnostic.Create(
+					Descriptors.AttributesRequireTypeOrPath, Location,
+					$"[{string.Join(", ", attributeList)}]");
+				break;
 			// A single attribute is valid.
 			case [ _ ]:
 			// The following are valid attribute combinations.
@@ -70,6 +86,10 @@ public class TypeEntityInfo : BaseEntityInfo
 				break;
 		}
 
+		// In in a built-in module, this entity is built-in, too.
+		if (Parent is ModuleEntityInfo { IsBuiltIn: true })
+			IsBuiltIn = true;
+
 		// Singletons are special kinds of components.
 		if (IsSingleton) IsComponent = true;
 	}

src/gaemstone/ECS/Module+Attributes.cs

@@ -40,6 +40,22 @@ public class AddAttribute<TEntity> : Attribute {  }
 public class AddAttribute<TRelation, TTarget> : Attribute {  }
 
 
+/// <summary>
+/// Marked entity automatically has the specified component added to it when
+/// automatically registered. Equivalent to <see cref="EntityBuilder.Set{TComponent}"/>.
+/// Arguments are passed to a valid constructor with matching arguments. Only
+/// attribute-safe primitives are allowed for the specified arguments.
+/// </summary>
+[AttributeUsage(AttributeTargets.Class | AttributeTargets.Struct
+              | AttributeTargets.Enum  | AttributeTargets.Method,
+                AllowMultiple = true)]
+public class SetAttribute<TComponent> : Attribute
+{
+	public object[] Arguments { get; }
+	public SetAttribute(params object[] args) => Arguments = args;
+}
+
+
 /// <seealso cref="IsA"/>
 public class IsAAttribute<TTarget> : AddAttribute<IsA, TTarget> {  }
 /// <seealso cref="ChildOf"/>

src/gaemstone/Flecs/Core.cs

@@ -7,35 +7,22 @@ public partial class Core
 {
 	// Entity Tags
 
-	[Tag] public struct Name {  }
-	[Tag] public struct Symbol {  }
-	[Tag] public struct Alias {  }
-
 	[Tag] public struct Module {  }
+	[Tag] public struct Private {  }
 	[Tag] public struct Prefab {  }
-	[Tag] public struct SlotOf {  }
 	[Tag] public struct Disabled {  }
-	[Tag] public struct Empty {  }
-
-
-	// Entities
-
-	[Entity, Path("*")] public struct Wildcard {  }
-	[Entity, Path("_")] public struct Any {  }
-	[Entity]            public struct This {  }
-	[Entity, Path("$")] public struct Variable {  }
-	[Entity]            public struct Flag {  }
 
-
-	// Entity Relationships
-
-	[Relation, Tag] public struct IsA {  }
-	[Relation, Tag] public struct ChildOf {  }
-	[Relation, Tag] public struct DependsOn {  }
+	[Tag] public struct SlotOf {  }
+	[Tag] public struct Flag {  }
 
 
 	// Component / Relationship Properties
 
+	[Entity, Path("*")]    public struct Wildcard {  }
+	[Entity, Path("_")]    public struct Any {  }
+	[Entity, Path("this")] public struct This {  }
+	[Entity, Path("$")]    public struct Variable {  }
+
 	[Tag] public struct Transitive {  }
 	[Tag] public struct Reflexive {  }
 	[Tag] public struct Symmetric {  }
@@ -45,16 +32,34 @@ public partial class Core
 	[Tag] public struct Union {  }
 	[Tag] public struct Exclusive {  }
 	[Tag] public struct Acyclic {  }
+	[Tag] public struct Traversable {  }
 	[Relation, Tag] public struct With {  }
 	[Tag] public struct OneOf {  }
 
 
+	// Entity Relationships
+
+	[Relation, Tag] public struct ChildOf {  }
+	[Relation, Tag] public struct IsA {  }
+	[Relation, Tag] public struct DependsOn {  }
+
+
+	// Identifier Tags
+
+	[Tag] public struct Name {  }
+	[Tag] public struct Symbol {  }
+	[Tag] public struct Alias {  }
+
+
 	// Observer Events
 
 	[Entity] public struct OnAdd {  }
 	[Entity] public struct OnRemove {  }
 	[Entity] public struct OnSet {  }
 	[Entity] public struct UnSet {  }
+
+	[Entity] public struct OnTableCreate {  }
+	[Entity] public struct OnTableDelete {  }
 	[Entity] public struct OnTableEmpty {  }
 	[Entity] public struct OnTableFilled {  }
 

src/gaemstone/Universe+Modules.cs

@@ -91,11 +91,18 @@ public class ModuleManager<TContext>
 
 		public ModuleInfo(Universe<TContext> universe)
 		{
-			var world   = universe.World;
-			var builder = world.New(T.Path);
-			var deps    = new List<ModuleDependency>();
+			var world = universe.World;
+
+			if (T.IsBuiltIn)
+			{
+				Entity = world.LookupPathOrThrow(T.Path);
+				Dependencies = Array.Empty<ModuleDependency>();
+			}
+			else
+			{
+				var builder = world.New(T.Path);
+				var deps    = new List<ModuleDependency>();
 
-			if (!T.IsBuiltIn) {
 				builder.Add<Module>();
 				foreach (var dependsPath in T.Dependencies) {
 					var dependency = world.LookupPathOrNull(dependsPath) ??
@@ -108,15 +115,14 @@ public class ModuleManager<TContext>
 					if (!isDepInit) builder.Add<Disabled>();
 					builder.Add<DependsOn>(dependency);
 				}
-			}
 
-			Entity = builder.Build().CreateLookup<T>();
-			Dependencies = deps.AsReadOnly();
+				Entity = builder.Build().CreateLookup<T>();
+				Dependencies = deps.AsReadOnly();
 
-			if (!T.IsBuiltIn)
 				// Ensure all parent entities have the Module tag set.
 				for (var p = Entity.Parent; p is Entity<TContext> parent; p = parent.Parent)
 					parent.Add<Module>();
+			}
 		}
 
 		public void Enable()