Process future ticks

nerudaj · May 18, 2024 · bc727f2 · bc727f2
1 parent 74fb965
commit bc727f2
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Showing 3 changed files with 43 additions and 13 deletions.
diff --git a/src/lib-app/include/app/AppStateIngame.hpp b/src/lib-app/include/app/AppStateIngame.hpp
@@ -83,6 +83,8 @@ class [[nodiscard]] AppStateIngame final : public dgm::AppState
     std::vector<mem::Rc<ControllerInterface>> inputs;
     Scene scene;
     RollbackManager<FrameState, 10> stateManager;
+    std::unordered_map<size_t, std::unordered_map<PlayerIdxType, InputSchema>>
+        futureInputs; // indexed by tick
     mem::Box<GameLoop> gameLoop;
     DemoFileHandler demoFileHandler;
     mem::Box<dgm::Camera> camera;

diff --git a/src/lib-app/src/app/AppStateIngame.cpp b/src/lib-app/src/app/AppStateIngame.cpp
@@ -150,8 +150,20 @@ void AppStateIngame::handleNetworkUpdate(const ServerUpdateData& update)
 
     for (auto&& inputData : update.inputs)
     {
-        stateManager.get(inputData.tick).inputs.at(inputData.clientId) =
-            inputData.input;
+        if (stateManager.isTickTooOld(inputData.tick))
+        {
+            throw std::runtime_error(
+                "Got outdated input, game desynced, exiting");
+        }
+        else if (stateManager.isTickTooNew(inputData.tick))
+        {
+            futureInputs[inputData.tick][inputData.clientId] = inputData.input;
+        }
+        else
+        {
+            stateManager.get(inputData.tick).inputs.at(inputData.clientId) =
+                inputData.input;
+        }
     }
 }
 
@@ -168,17 +180,22 @@ AppStateIngame::FrameState AppStateIngame::snapshotInputsIntoNewFrameState()
                              })
                          | std::ranges::to<decltype(FrameState::inputs)>() };
 
+    if (futureInputs.contains(scene.tick))
+    {
+        for (auto&& [playerIdx, input] : futureInputs[scene.tick])
+        {
+            state.inputs.at(playerIdx) = input;
+        }
+        futureInputs.erase(scene.tick);
+    }
+
     if (!hasFocus)
     {
         state.inputs[client->getMyIndex()] = InputSchema {};
     }
 
     client->sendCurrentFrameInputs(lastTick, state.inputs);
 
-    // The following lines disables local input and drives everything throught
-    // the network
-    state.inputs[client->getMyIndex()] = InputSchema {};
-
     // TODO: rework demos
     /*if (settings->cmdSettings.playDemo)
     {
@@ -190,10 +207,12 @@ AppStateIngame::FrameState AppStateIngame::snapshotInputsIntoNewFrameState()
         }
         state.inputs[0] = nlohmann::json::parse(line);
     }
-    else
-    {
-        demoFileHandler.writeLine(nlohmann::json(state.inputs[0]).dump());
-    }*/
+    else*/
+    demoFileHandler.writeLine(nlohmann::json(client->getMyIndex()).dump());
+
+    // The following lines disables local input and drives everything throught
+    // the network
+    state.inputs[client->getMyIndex()] = InputSchema {};
 
     return state;
 }

diff --git a/src/lib-game/include/utils/RollbackManager.hpp b/src/lib-game/include/utils/RollbackManager.hpp
@@ -14,6 +14,7 @@ class [[nodiscard]] RollbackManager final
     using BufferIndexType = BufferType::BufferIndexType;
 
 public:
+    // insert until tick
     void insert(dgm::UniversalReference<T> auto&& item, size_t tick)
     {
         assert(buffer.isEmpty() || tick > endIterator.tick);
@@ -29,7 +30,7 @@ class [[nodiscard]] RollbackManager final
     [[nodiscard]] constexpr std::expected<BufferIndexType, ErrorMessage>
     getIndexForTick(size_t tick) noexcept
     {
-        if (endIterator.tick < tick || (endIterator.tick - tick) >= Capacity)
+        if (isTickTooNew(tick) || isTickTooOld(tick))
             return std::unexpected(std::format(
                 "Requested index is not in buffer, endIterator.tick: {}, tick: "
                 "{}, Capacity: {}",
@@ -40,8 +41,6 @@ class [[nodiscard]] RollbackManager final
         return endIterator.bufferIdx - (endIterator.tick - tick);
     }
 
-    // TODO: forEachItemSinceTickXYZ
-
     template<
         size_t HowMuchToUnroll = Capacity,
         class = std::enable_if<HowMuchToUnroll <= Capacity>>
@@ -76,6 +75,16 @@ class [[nodiscard]] RollbackManager final
         return buffer.getSize() == 1u;
     }
 
+    [[nodiscard]] constexpr bool isTickTooOld(size_t tick) const noexcept
+    {
+        return endIterator.tick > tick && (endIterator.tick - tick) >= Capacity;
+    }
+
+    [[nodiscard]] constexpr bool isTickTooNew(size_t tick) const noexcept
+    {
+        return buffer.isEmpty() || tick > endIterator.tick;
+    }
+
 private:
     [[nodiscard]] constexpr auto&& last(this auto&& self) noexcept
     {