limit chunks non-unloading zone to a circle

src/frontend/hud.cpp

@@ -270,6 +270,7 @@ void Hud::updateHotbarControl() {
 void Hud::updateWorldGenDebug() {
     auto& level = frontend.getLevel();
     const auto& chunks = *player.chunks;
+    uint padding = engine.getSettings().chunks.padding.get();
     auto generator =
         frontend.getController()->getChunksController()->getGenerator();
     auto debugInfo = generator->createDebugInfo();
@@ -291,8 +292,15 @@ void Hud::updateWorldGenDebug() {
             int ax = x - (width - areaWidth) / 2;
             int az = z - (height - areaHeight) / 2;
 
-            data[(flippedZ * width + x) * 4 + 1] = 
-                chunks.getChunk(ax + ox, az + oz) ? 255 : 0;
+            bool isInLoadingZone =
+                frontend.getController()
+                    ->getChunksController()
+                    ->isInLoadingZone(player, padding, ax + ox, az + oz);
+
+            data[(flippedZ * width + x) * 4 + 1] =
+                chunks.getChunk(ax + ox, az + oz)
+                    ? (isInLoadingZone ? 255 : 128)
+                    : 0;
             data[(flippedZ * width + x) * 4 + 0] = 
                 level.chunks->fetch(ax + ox, az + oz) ? 255 : 0;
 

src/logic/ChunksController.cpp

@@ -60,18 +60,55 @@ void ChunksController::update(
     }
 }
 
-bool ChunksController::loadVisible(const Player& player, uint padding) const {
+bool ChunksController::isInLoadingZone(
+    const Player& player, uint padding, int x, int z
+) const {
     const auto& chunks = *player.chunks;
     int sizeX = chunks.getWidth();
     int sizeY = chunks.getHeight();
 
+    int minDistance = ((sizeX - padding * 2) / 2) * ((sizeY - padding * 2) / 2);
+
+    int lx = (x - chunks.getOffsetX()) - sizeX / 2;
+    int lz = (z - chunks.getOffsetY()) - sizeY / 2;
+    int distance = (lx * lx + lz * lz);
+
+    return distance < minDistance;
+}
+
+bool ChunksController::loadVisible(const Player& player, uint padding) const {
+    auto& chunks = *player.chunks;
+    int sizeX = chunks.getWidth();
+    int sizeY = chunks.getHeight();
+
     int nearX = 0;
     int nearZ = 0;
     bool assigned = false;
     int minDistance = ((sizeX - padding * 2) / 2) * ((sizeY - padding * 2) / 2);
+    int maxDistance = ((sizeX) / 2) * ((sizeY) / 2);
+    for (uint z = 0; z < sizeY; z++) {
+        for (uint x = 0; x < sizeX; x++) {
+            int index = z * sizeX + x;
+            int lx = x - sizeX / 2;
+            int lz = z - sizeY / 2;
+            int distance = (lx * lx + lz * lz);
+            auto& chunk = chunks.getChunks()[index];
+            if (chunk != nullptr) {
+                if (distance >= maxDistance) {
+                    chunks.remove(
+                        x + chunks.getOffsetX(), z + chunks.getOffsetY()
+                    );
+                }
+                continue;
+            }
+        }
+    }
     for (uint z = padding; z < sizeY - padding; z++) {
         for (uint x = padding; x < sizeX - padding; x++) {
             int index = z * sizeX + x;
+            int lx = x - sizeX / 2;
+            int lz = z - sizeY / 2;
+            int distance = (lx * lx + lz * lz);
             auto& chunk = chunks.getChunks()[index];
             if (chunk != nullptr) {
                 if (chunk->flags.loaded && !chunk->flags.lighted) {
@@ -81,9 +118,7 @@ bool ChunksController::loadVisible(const Player& player, uint padding) const {
                 }
                 continue;
             }
-            int lx = x - sizeX / 2;
-            int lz = z - sizeY / 2;
-            int distance = (lx * lx + lz * lz);
+
             if (distance < minDistance) {
                 minDistance = distance;
                 nearX = x;

src/logic/ChunksController.hpp

@@ -32,6 +32,8 @@ public:
         int64_t maxDuration, int loadDistance, uint padding, Player& player
     ) const;
 
+    bool isInLoadingZone(const Player& player, uint padding, int x, int z) const;
+
     const WorldGenerator* getGenerator() const {
         return generator.get();
     }

src/util/AreaMap2D.hpp

@@ -114,6 +114,17 @@ namespace util {
             return true;
         }
 
+        void remove(TCoord x, TCoord y) {
+            auto lx = x - offsetX;
+            auto ly = y - offsetY;
+            if (lx < 0 || ly < 0 || lx >= sizeX || ly >= sizeY) {
+                return;
+            }
+            if (outCallback)
+                outCallback(x, y, firstBuffer[ly * sizeX + lx]);
+            firstBuffer[ly * sizeX + lx] = T{};
+        }
+
         void setOutCallback(const OutCallback& callback) {
             outCallback = callback;
         }

src/voxels/Chunks.cpp

@@ -419,3 +419,7 @@ void Chunks::getVoxels(VoxelsVolume& volume, bool backlight) const {
 void Chunks::saveAndClear() {
     areaMap.clear();
 }
+
+void Chunks::remove(int32_t x, int32_t z) {
+    areaMap.remove(x, z);
+}

src/voxels/Chunks.hpp

@@ -133,6 +133,8 @@ public:
 
     void saveAndClear();
 
+    void remove(int32_t x, int32_t z);
+
     const std::vector<std::shared_ptr<Chunk>>& getChunks() const {
         return areaMap.getBuffer();
     }