Properly link flecs library

engine/libs/flecs/examples/cpp/systems/startup_system/include/startup_system.h

@@ -0,0 +1,16 @@
+#ifndef STARTUP_SYSTEM_H
+#define STARTUP_SYSTEM_H
+
+/* This generated file contains includes for project dependencies */
+#include "startup_system/bake_config.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+

engine/libs/flecs/examples/cpp/systems/startup_system/include/startup_system/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 STARTUP_SYSTEM_BAKE_CONFIG_H
+#define STARTUP_SYSTEM_BAKE_CONFIG_H
+
+/* Headers of public dependencies */
+#include <flecs.h>
+
+#endif
+

engine/libs/flecs/examples/cpp/systems/startup_system/project.json

@@ -0,0 +1,11 @@
+{
+    "id": "startup_system",
+    "type": "application",
+    "value": {
+        "use": [
+            "flecs"
+        ],
+        "language": "c++",
+        "public": false
+    }
+}

engine/libs/flecs/examples/cpp/systems/startup_system/src/main.cpp

@@ -0,0 +1,39 @@
+#include <startup_system.h>
+#include <iostream>
+
+// Startup systems are systems registered with the EcsOnStart phase, and are
+// only ran during the first frame. Just like with regular phases, custom phases
+// can depend on the EcsOnStart phase (see custom_phases example). Phases that 
+// depend on EcsOnStart are also only ran during the first frame.
+//
+// Other than that, startup systems behave just like regular systems (they can
+// match components, can introduce merge points), with as only exception that
+// they are guaranteed to always run on the main thread. 
+
+int main(int, char *[]) {
+    flecs::world ecs;
+
+    // Startup system
+    ecs.system("Startup")
+        .kind(flecs::OnStart)
+        .iter([](flecs::iter& it) {
+            std::cout << it.system().name() << "\n";
+        });
+
+    // Regular system
+    ecs.system("Update")
+        .iter([](flecs::iter& it) {
+            std::cout << it.system().name() << "\n";
+        });
+
+    // First frame. This runs both the Startup and Update systems
+    ecs.progress();
+
+    // Second frame. This runs only the Update system
+    ecs.progress();
+
+    // Output
+    //   Startup
+    //   Update
+    //   Update
+}