1 files changed, 26 insertions, 6 deletions

diff --git a/source/core/StarNetElement.hpp b/source/core/StarNetElement.hpp
index dd909b8..7d73b85 100644
--- a/source/core/StarNetElement.hpp
+++ b/source/core/StarNetElement.hpp
@@ -9,7 +9,7 @@ namespace Star {
 class NetElementVersion {
 public:
   uint64_t current() const;
-  void increment();
+  uint64_t increment();
 
 private:
   uint64_t m_version = 0;
@@ -20,15 +20,15 @@ class NetElement {
 public:
   virtual ~NetElement() = default;
 
-  // A network of NetElements will have a shared monotinically increasing
+  // A network of NetElements will have a shared monotonically increasing
   // NetElementVersion.  When elements are updated, they will mark the version
   // number at the time they are updated so that a delta can be constructed
   // that contains only changes since any past version.
   virtual void initNetVersion(NetElementVersion const* version = nullptr) = 0;
 
   // Full store / load of the entire element.
-  virtual void netStore(DataStream& ds) const = 0;
-  virtual void netLoad(DataStream& ds) = 0;
+  virtual void netStore(DataStream& ds, NetCompatibilityRules rules) const = 0;
+  virtual void netLoad(DataStream& ds, NetCompatibilityRules rules) = 0;
 
   // Enables interpolation mode.  If interpolation mode is enabled, then
   // NetElements will delay presenting incoming delta data for the
@@ -46,14 +46,34 @@ public:
   // the version at the time of the *last* call to writeDelta, + 1.  If
   // fromVersion is 0, this will always write the full state.  Should return
   // true if a delta was needed and was written to DataStream, false otherwise.
-  virtual bool writeNetDelta(DataStream& ds, uint64_t fromVersion) const = 0;
+  virtual bool writeNetDelta(DataStream& ds, uint64_t fromVersion, NetCompatibilityRules rules) const = 0;
   // Read a delta written by writeNetDelta.  'interpolationTime' is the time in
   // the future that data from this delta should be delayed and smoothed into,
   // if interpolation is enabled.
-  virtual void readNetDelta(DataStream& ds, float interpolationTime = 0.0) = 0;
+  virtual void readNetDelta(DataStream& ds, float interpolationTime = 0.0f, NetCompatibilityRules rules = {}) = 0;
   // When extrapolating, it is important to notify when a delta WOULD have been
   // received even if no deltas are produced, so no extrapolation takes place.
   virtual void blankNetDelta(float interpolationTime);
+
+  VersionNumber compatibilityVersion() const;
+  void setCompatibilityVersion(VersionNumber version);
+  bool checkWithRules(NetCompatibilityRules const& rules) const;
+private:
+  VersionNumber m_netCompatibilityVersion = AnyVersion;
 };
 
+inline VersionNumber NetElement::compatibilityVersion() const {
+  return m_netCompatibilityVersion;
+}
+
+inline void NetElement::setCompatibilityVersion(VersionNumber version) {
+  m_netCompatibilityVersion = version;
+}
+
+inline bool NetElement::checkWithRules(NetCompatibilityRules const& rules) const {
+  if (m_netCompatibilityVersion != AnyVersion)
+    return rules.version() >= m_netCompatibilityVersion;
+  return true;
+}
+
 }