Add function ResourceTypeID to get resource ID from reflect.Type` (#…

…420)

CHANGELOG.md

@@ -1,5 +1,9 @@
 ## [[unpublished]](https://github.com/mlange-42/arche/compare/v0.12.0...main)
 
+### Features
+
+* Adds function `ResourceTypeID` to register/get a resource ID from a `reflect.Type` (#420)
+
 ### Other
 
 * Fix component type in examples/base (#419)

ecs/functions.go

@@ -60,6 +60,16 @@ func ResourceID[T any](w *World) ResID {
 	return w.resourceID(tp)
 }
 
+// ResourceTypeID returns the [ResID] for a resource type.
+// Registers the type if it is not already registered.
+//
+// See [ResourceID] for a more commonly used generic variant.
+//
+// The number of resources per [World] is limited to [MaskTotalBits].
+func ResourceTypeID(w *World, tp reflect.Type) ResID {
+	return w.resourceID(tp)
+}
+
 // ResourceIDs returns a list of all registered resource IDs.
 func ResourceIDs(w *World) []ResID {
 	intIds := w.resources.registry.IDs

ecs/functions_test.go

@@ -13,14 +13,19 @@ func TestCompResIDs(t *testing.T) {
 	posID := ComponentID[Position](&w)
 	rotID := ComponentID[rotation](&w)
 
+	tPosID := TypeID(&w, reflect.TypeOf(Position{}))
+	tRotID := TypeID(&w, reflect.TypeOf(rotation{}))
+
 	res1ID := ResourceID[Position](&w)
 	res2ID := ResourceID[Velocity](&w)
 
-	tPosID := TypeID(&w, reflect.TypeOf(Position{}))
-	tRotID := TypeID(&w, reflect.TypeOf(rotation{}))
+	tRes1ID := ResourceTypeID(&w, reflect.TypeOf(Position{}))
+	tRes2ID := ResourceTypeID(&w, reflect.TypeOf(Velocity{}))
 
 	assert.Equal(t, posID, tPosID)
 	assert.Equal(t, rotID, tRotID)
+	assert.Equal(t, res1ID, tRes1ID)
+	assert.Equal(t, res2ID, tRes2ID)
 
 	assert.Equal(t, uint8(0), posID.id)
 	assert.Equal(t, uint8(1), rotID.id)