Schedule systems based on their declared dependencies

[libs/game.git] / source / game / stage.cpp

diff --git a/source/game/stage.cpp b/source/game/stage.cpp
index 83176104348538a148d667c9126fff11107e7a8b..3888410a43c8bc976034b753693b56ab35f16d72 100644 (file)
--- a/source/game/stage.cpp
+++ b/source/game/stage.cpp
@@ -1,4 +1,7 @@
 #include "stage.h"
+#include <msp/debug/demangle.h>
+#include <msp/strings/format.h>
+#include "accessguard.h"
 #include "camera.h"
 #include "root.h"
 #include "system.h"
@@ -7,11 +10,13 @@ using namespace std;
 
 namespace Msp::Game {
 
-Stage::Stage(DataFile::Collection &r):
+Stage::Stage(Reflection::Reflector &f, DataFile::Collection &r):
+       reflector(f),
        resources(r),
        event_source(event_bus),
        event_observer(event_bus),
-       root(std::make_unique<Root>(*this))
+       root(std::make_unique<Root>(*this)),
+       scheduler(reflector)
 {
        event_observer.observe<Events::ComponentCreated>([this](auto &e){
                if(!active_camera)
@@ -26,7 +31,9 @@ Stage::~Stage()
 
 void Stage::remove_system(System &s)
 {
+       scheduler.remove_system(s);
        erase_if(systems, [&s](auto &p){ return p.get()==&s; });
+       pending_reschedule = true;
 }
 
 void Stage::set_active_camera(Handle<Camera> c)
@@ -35,10 +42,49 @@ void Stage::set_active_camera(Handle<Camera> c)
        event_source.emit<Events::CameraChanged>(active_camera);
 }
 
+void Stage::synthesize_initial_events(EventObserver &target_observer)
+{
+       synthesize_initial_events(Handle<Entity>::from_object(root.get()), target_observer);
+       if(active_camera)
+               event_source.emit_to<Events::CameraChanged>(target_observer, active_camera);
+}
+
+void Stage::synthesize_initial_events(Handle<Entity> entity, EventObserver &target_observer)
+{
+       for(Handle<Component> c: entity->get_components())
+               event_source.emit_to<Events::ComponentCreated>(target_observer, c);
+       for(Handle<Entity> e: entity->get_children())
+               synthesize_initial_events(e, target_observer);
+       event_source.emit_to<Events::EntityCreated>(target_observer, entity);
+}
+
 void Stage::tick(Time::TimeDelta dt)
 {
-       for(const auto &s: systems)
-               s->tick(dt);
+       if(pending_reschedule)
+       {
+               scheduler.schedule();
+               pending_reschedule = false;
+       }
+
+       {
+#ifdef DEBUG
+               AccessGuard::BlockForScope _block;
+#endif
+               for(const SystemScheduler::Group &g: scheduler.get_groups())
+                       for(System *s: g.systems)
+                       {
+                               System::Activator act(*s);
+                               try
+                               {
+                                       s->tick(dt);
+                               }
+                               catch(const invalid_access &exc)
+                               {
+                                       throw invalid_access(format("%s by %s", exc.what(), Debug::demangle(typeid(*s).name())));
+                               }
+                       }
+       }
+
        for(const auto &s: systems)
                s->deferred_tick();
 }