1 files changed, 132 insertions, 0 deletions
diff --git a/source/game/StarWireProcessor.cpp b/source/game/StarWireProcessor.cpp
new file mode 100644
index 0000000..9b0d674
--- /dev/null
+++ b/source/game/StarWireProcessor.cpp
@@ -0,0 +1,132 @@
+#include "StarWireProcessor.hpp"
+#include "StarWorldStorage.hpp"
+#include "StarEntityMap.hpp"
+#include "StarWireEntity.hpp"
+#include "StarLogging.hpp"
+
+namespace Star {
+
+WireProcessor::WireProcessor(WorldStoragePtr worldStorage) {
+  m_worldStorage = worldStorage;
+}
+
+void WireProcessor::process() {
+  // First, populate all the working entities that are already live
+  m_worldStorage->entityMap()->forAllEntities([&](EntityPtr const& entity) {
+    if (auto wireEntity = as<WireEntity>(entity.get()))
+      populateWorking(wireEntity);
+  });
+
+  // Then, scan the network of each entity in the working set.  This may, as a
+  // side effect, load further unconnected wire entities. Because our policy is
+  // to try as hard as possible to make sure that the entire wire entity
+  // network to be loaded at once or not at all, we need to make sure that each
+  // new disconnected entity also has its network loaded and so on.  Thus, if
+  // the working entities size changes during scanning, simply scan the whole
+  // thing again until the size stops changing.
+  while (true) {
+    size_t oldWorkingSize = m_workingWireEntities.size();
+    for (auto const& p : m_workingWireEntities.keys()) {
+      if (!m_workingWireEntities.get(p).networkLoaded)
+        loadNetwork(p);
+    }
+    if (m_workingWireEntities.size() == oldWorkingSize)
+      break;
+  }
+
+  for (auto const& p : m_workingWireEntities)
+    p.second.wireEntity->evaluate(this);
+
+  m_workingWireEntities.clear();
+}
+
+bool WireProcessor::readInputConnection(WireConnection const& connection) {
+  if (auto wes = m_workingWireEntities.ptr(connection.entityLocation))
+    return wes->outputStates.get(connection.nodeIndex);
+  return false;
+}
+
+void WireProcessor::populateWorking(WireEntity* wireEntity) {
+  auto p = m_workingWireEntities.insert(wireEntity->tilePosition(), WireEntityState{nullptr, {}, false});
+  if (!p.second) {
+    if (p.first->second.wireEntity != wireEntity)
+      Logger::debug("Multiple wire entities share tile position: %s", wireEntity->position());
+    return;
+  }
+  auto& wes = p.first->second;
+  wes.wireEntity = wireEntity;
+  size_t outputNodeCount = wes.wireEntity->nodeCount(WireDirection::Output);
+  wes.outputStates.resize(outputNodeCount);
+  for (size_t i = 0; i < outputNodeCount; ++i)
+    wes.outputStates[i] = wes.wireEntity->nodeState({WireDirection::Output, i});
+}
+
+void WireProcessor::loadNetwork(Vec2I tilePosition) {
+  HashSet<WorldStorage::Sector> networkSectors;
+  Maybe<float> highestTtl;
+
+  // Recursively load a given WireEntity at the given position.  Returns true
+  // if that wire entity was found.
+  // TODO: This is depth first recursive, because that is the simplest thing,
+  // but if this causes issues with recursion depth it can be changed.
+  function<bool(Vec2I)> doLoad;
+  doLoad = [&](Vec2I const& pos) {
+    auto sector = m_worldStorage->sectorForPosition(pos);
+    if (!sector)
+      return false;
+
+    if (m_worldStorage->sectorLoadLevel(*sector) == SectorLoadLevel::Loaded) {
+      auto ttl = *m_worldStorage->sectorTimeToLive(*sector);
+      if (highestTtl)
+        highestTtl = max(*highestTtl, ttl);
+      else
+        highestTtl = ttl;
+    } else {
+      m_worldStorage->loadSector(*sector);
+      m_worldStorage->entityMap()->forEachEntity(RectF(*m_worldStorage->regionForSector(*sector)), [&](EntityPtr const& entity) {
+          if (auto wireEntity = as<WireEntity>(entity.get()))
+            populateWorking(wireEntity);
+        });
+    }
+
+    auto wes = m_workingWireEntities.ptr(pos);
+    if (!wes)
+      return false;
+    if (wes->networkLoaded)
+      return true;
+
+    wes->networkLoaded = true;
+    networkSectors.add(*sector);
+
+    // Recursively descend into all the inbound and outbound nodes, and if we
+    // ever cannot load the wire entity for a connection, go ahead and remove
+    // the connection.
+    size_t inboundNodeCount = wes->wireEntity->nodeCount(WireDirection::Input);
+    for (size_t i = 0; i < inboundNodeCount; ++i) {
+      for (auto const& connection : wes->wireEntity->connectionsForNode({WireDirection::Input, i})) {
+        if (!doLoad(connection.entityLocation))
+          wes->wireEntity->removeNodeConnection({WireDirection::Input, i}, connection);
+      }
+    }
+    size_t outboundNodeCount = wes->wireEntity->nodeCount(WireDirection::Output);
+    for (size_t i = 0; i < outboundNodeCount; ++i) {
+      for (auto const& connection : wes->wireEntity->connectionsForNode({WireDirection::Output, i})) {
+        if (!doLoad(connection.entityLocation))
+          wes->wireEntity->removeNodeConnection({WireDirection::Output, i}, connection);
+      }
+    }
+    return true;
+  };
+
+  doLoad(tilePosition);
+
+  // Set the sector ttl for the entire network to be equal to the highest
+  // entry, so that the entire network either lives or dies together, but
+  // without artificially extending the lifetime of the network.
+  if (highestTtl) {
+    for (auto const& sector : networkSectors)
+      m_worldStorage->setSectorTimeToLive(sector, *highestTtl);
+  }
+}
+
+}