send map when arriving late

src/td/simulation/ClientSimulation.cpp

@@ -30,14 +30,22 @@ ClientSimulation::ClientSimulation(std::shared_ptr<game::World> a_World, GameHis
 	Step();
 }
 
-ClientSimulation::ClientSimulation(std::shared_ptr<game::World> a_World, std::uint64_t a_StepTime) :
+ClientSimulation::ClientSimulation(
+	std::shared_ptr<game::World> a_World, std::uint64_t a_StepTime, const std::vector<protocol::LockStep>& a_FirstSteps) :
 	m_StepTime(a_StepTime),
 	m_World(a_World),
 	m_History(std::numeric_limits<StepTime>::max()),
 	m_CurrentTime(0),
 	m_CurrentStep(0),
 	m_LastSnapshot(std::make_shared<WorldSnapshot>()),
-	m_LastValidStep(0) {}
+	m_LastValidStep(0) {
+	if (!a_FirstSteps.empty()) {
+		for (std::size_t i = 0; i < a_FirstSteps.size(); i++) {
+			m_History[i] = a_FirstSteps[i];
+		}
+		FastForward(a_FirstSteps.size());
+	}
+}
 
 float ClientSimulation::Update(float a_Delta) {
 	// TODO: handle freezes (m_CurrentTime > 2 * m_StepTime)

src/td/simulation/ServerSimulation.cpp

@@ -47,6 +47,16 @@ protocol::packets::LockStepResponsePacket ServerSimulation::GetResponse(
 	return {result};
 }
 
+std::vector<protocol::LockStep> ServerSimulation::GetFirstLocksteps() {
+	std::vector<protocol::LockStep> result;
+	if (m_CurrentTime <= LOCKSTEP_BUFFER_SIZE)
+		return result;
+
+	result.reserve(m_CurrentTime);
+	result.insert(result.begin(), m_History.begin(), m_History.begin() + m_CurrentTime);
+	return result;
+}
+
 
 }  // namespace sim
 }  // namespace td