Add compilation flag to disable automatic component registration

SanderMertens · Dec 22, 2023 · d44f1b3 · d44f1b3
1 parent 8c8ec42
commit d44f1b3
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Showing 8 changed files with 111 additions and 0 deletions.
diff --git a/flecs.h b/flecs.h
@@ -142,6 +142,16 @@
  */
 // #define FLECS_CUSTOM_BUILD
 
+/** \def FLECS_CPP_NO_AUTO_REGISTRATION
+ * When set, the C++ API will require that components are registered before they
+ * are used. This is useful in multithreaded applications, where components need
+ * to be registered beforehand, and to catch issues in projects where component 
+ * registration is mandatory. Disabling automatic component registration also
+ * slightly improves performance.
+ * The C API is not affected by this feature.
+ */
+// #define FLECS_CPP_NO_AUTO_REGISTRATION
+
 #ifndef FLECS_CUSTOM_BUILD
 // #define FLECS_C          /**< C API convenience macros, always enabled */
 #define FLECS_CPP           /**< C++ API */
@@ -25680,6 +25690,7 @@ struct cpp_type_impl {
         bool allow_tag = true)
     {
         // If no id has been registered yet, do it now.
+#ifndef FLECS_CPP_NO_AUTO_REGISTRATION
         if (!registered(world)) {
             ecs_entity_t prev_scope = 0;
             ecs_id_t prev_with = 0;
@@ -25708,6 +25719,15 @@ struct cpp_type_impl {
                 ecs_set_scope(world, prev_scope);
             }
         }
+#else
+        (void)world;
+        (void)name;
+        (void)allow_tag;
+
+        ecs_assert(registered(world), ECS_INVALID_OPERATION, 
+            "component '%s' was not registered before use",
+            type_name<T>());
+#endif
 
         // By now we should have a valid identifier
         ecs_assert(s_id != 0, ECS_INTERNAL_ERROR, NULL);

diff --git a/include/flecs.h b/include/flecs.h
@@ -140,6 +140,16 @@
  */
 // #define FLECS_CUSTOM_BUILD
 
+/** \def FLECS_CPP_NO_AUTO_REGISTRATION
+ * When set, the C++ API will require that components are registered before they
+ * are used. This is useful in multithreaded applications, where components need
+ * to be registered beforehand, and to catch issues in projects where component 
+ * registration is mandatory. Disabling automatic component registration also
+ * slightly improves performance.
+ * The C API is not affected by this feature.
+ */
+// #define FLECS_CPP_NO_AUTO_REGISTRATION
+
 #ifndef FLECS_CUSTOM_BUILD
 // #define FLECS_C          /**< C API convenience macros, always enabled */
 #define FLECS_CPP           /**< C++ API */

diff --git a/include/flecs/addons/cpp/component.hpp b/include/flecs/addons/cpp/component.hpp
@@ -217,6 +217,7 @@ struct cpp_type_impl {
         bool allow_tag = true)
     {
         // If no id has been registered yet, do it now.
+#ifndef FLECS_CPP_NO_AUTO_REGISTRATION
         if (!registered(world)) {
             ecs_entity_t prev_scope = 0;
             ecs_id_t prev_with = 0;
@@ -245,6 +246,15 @@ struct cpp_type_impl {
                 ecs_set_scope(world, prev_scope);
             }
         }
+#else
+        (void)world;
+        (void)name;
+        (void)allow_tag;
+
+        ecs_assert(registered(world), ECS_INVALID_OPERATION, 
+            "component '%s' was not registered before use",
+            type_name<T>());
+#endif
 
         // By now we should have a valid identifier
         ecs_assert(s_id != 0, ECS_INTERNAL_ERROR, NULL);

diff --git a/test/custom_builds/cpp/no_auto_registration/.gitignore b/test/custom_builds/cpp/no_auto_registration/.gitignore
@@ -0,0 +1,5 @@
+.bake_cache
+.DS_Store
+.vscode
+gcov
+bin
diff --git a/test/custom_builds/cpp/no_auto_registration/include/no_auto_registration.h b/test/custom_builds/cpp/no_auto_registration/include/no_auto_registration.h
@@ -0,0 +1,16 @@
+#ifndef NO_AUTO_REGISTRATION_H
+#define NO_AUTO_REGISTRATION_H
+
+/* This generated file contains includes for project dependencies */
+#include "no_auto_registration/bake_config.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
diff --git a/test/custom_builds/cpp/no_auto_registration/include/no_auto_registration/bake_config.h b/test/custom_builds/cpp/no_auto_registration/include/no_auto_registration/bake_config.h
@@ -0,0 +1,24 @@
+/*
+                                   )
+                                  (.)
+                                  .|.
+                                  | |
+                              _.--| |--._
+                           .-';  ;`-'& ; `&.
+                          \   &  ;    &   &_/
+                           |"""---...---"""|
+                           \ | | | | | | | /
+                            `---.|.|.|.---'
+
+ * This file is generated by bake.lang.c for your convenience. Headers of
+ * dependencies will automatically show up in this file. Include bake_config.h
+ * in your main project file. Do not edit! */
+
+#ifndef NO_AUTO_REGISTRATION_BAKE_CONFIG_H
+#define NO_AUTO_REGISTRATION_BAKE_CONFIG_H
+
+/* Headers of public dependencies */
+#include "../../deps/flecs.h"
+
+#endif
+
diff --git a/test/custom_builds/cpp/no_auto_registration/project.json b/test/custom_builds/cpp/no_auto_registration/project.json
@@ -0,0 +1,15 @@
+{
+    "id": "no_auto_registration",
+    "type": "application",
+    "value": {
+        "use": [
+            "flecs"
+        ],
+        "public": false,
+        "standalone": true,
+        "language": "c++"
+    },
+    "lang.cpp": {
+        "defines": ["FLECS_CPP_NO_AUTO_REGISTRATION"]
+    }
+}
diff --git a/test/custom_builds/cpp/no_auto_registration/src/main.cpp b/test/custom_builds/cpp/no_auto_registration/src/main.cpp
@@ -0,0 +1,11 @@
+#include <no_auto_registration.h>
+#include <iostream>
+
+int main(int, char *[]) {
+    flecs::world world;
+
+    world.import<flecs::units>();
+    world.import<flecs::monitor>();
+
+    return 0;
+}