update SurroundMap (WIP)

src/world/generator/SurroundMap.cpp

@@ -0,0 +1,117 @@
+#include "SurroundMap.hpp"
+
+#include <queue>
+#include <cstring>
+#include <stdexcept>
+
+void SurroundMap::resetMarks() {
+    for (auto& [_, entry] : entries) {
+        entry.marked = false;
+    }
+}
+
+bool SurroundMap::createEntry(const glm::ivec2& origin) {
+    auto& entry = entries[origin];
+    if (entry.confirmed) {
+        return false;
+    }
+    entry.confirmed = true;
+
+    // calculate initial number of surrounding entries (any level)
+    int bitOffset = 0;
+    for (int y = -1; y <= 1; y++) {
+        for (int x = -1; x <= 1; x++) {
+            if (x == y && x == 0) {
+                continue;
+            }
+            const auto& found = entries.find(origin + glm::ivec2(x, y));
+            if (found != entries.end()) {
+                entry.surrounding |= (1 << bitOffset);
+                if (found->second.level == 0) {
+                    found->second.surrounding |= (1 << (7 - bitOffset));
+                }
+            }
+            bitOffset++;
+        }
+    }
+    return true;
+}
+
+std::vector<glm::ivec2> SurroundMap::upgrade() {
+    std::vector<glm::ivec2> expansion;
+    std::queue<glm::ivec2> expanding;
+    for (const auto& [pos, entry] : entries) {
+        if (entry.confirmed && entry.surrounding != 0xFF) {
+            expanding.push(pos);
+        }
+    }
+    while (!expanding.empty()) {
+        assert(expanding.size() < 64);
+
+        glm::ivec2 pos = expanding.front();
+        expanding.pop();
+
+        const auto& found = entries.find(pos);
+        assert(found != entries.end() && "concurrent modification");
+
+        auto& entry = found->second;
+        int uplevelSurrounding = 0;
+        int bitOffset = 0;
+        for (int y = -1; y <= 1; y++) {
+            for (int x = -1; x <= 1; x++) {
+                if (x == y && x == 0) {
+                    continue;
+                }
+                glm::ivec2 npos = {pos.x+x, pos.y+y};
+                const auto& nfound = entries.find(npos);
+                
+                if (entry.surrounding & (1 << bitOffset)) {
+                    auto& nentry = nfound->second;
+                    if (nentry.level > entry.level) {
+                        uplevelSurrounding |= (1 << bitOffset);
+                    }
+                    bitOffset++;
+                    continue;
+                }
+                if (entry.level == 0) {
+                    // neighbour entry does not exist
+                    createEntry(npos);
+                    expansion.push_back(npos);
+                } else{
+                    assert(nfound != entries.end() && "invalid map state");
+                    if (nfound->second.level == entry.level + 1) {
+                        nfound->second.surrounding |= (1 << (7 - bitOffset));
+                        expanding.push(npos);
+                    }
+                }
+                bitOffset++;
+            }
+        }
+        // level up
+        entry.surrounding = uplevelSurrounding;
+        entry.level++;
+    }
+    return expansion;
+}
+
+void SurroundMap::getLevels(unsigned char* out, int width, int height, int ox, int oy) const {
+    std::memset(out, 0, width * height);
+    for (const auto& [pos, entry] : entries) {
+        int x = pos.x - ox;
+        int y = pos.y - oy;
+        if (x < 0 || x >= width || y < 0 || y >= height) {
+            continue;
+        }
+
+        int surroundNum = 0;
+        for (int i = 0; i < 8; i++) {
+            if (entry.surrounding & (1 << i)) {
+                surroundNum++;
+            }
+        }
+        if (surroundNum) {
+            out[y * width + x] = surroundNum + 1;
+        }
+        out[y * width + x] = entry.level + 1;
+    }
+}

src/world/generator/SurroundMap.hpp

@@ -10,11 +10,13 @@ class SurroundMap {
         /// @brief Level is increased when all surrounding (8) entries having
         // greather or equal confirmed level
         int level = 0;
-        /// @brief number of surrounding entries having greather or equal
-        /// confirmed level
-        int surrounding = 0;
+        /// @brief bits storing surrounding entries having greather or equal
+        /// confirmed level.
+        /// 0 - is x=-1,y=-1 offset, 1 is x=0,y=-1, ... 7 is x=1,y=1
+        /// (Prevents extra access to the entries hashmap)
+        uint8_t surrounding = 0x0;
         /// @brief level confirmed status (entry is ready to expand)
-        bool confirmed = true;
+        bool confirmed = false;
         /// @brief mark used on sweep event (extra isles garbage collection)
         bool marked = false;
     };
@@ -24,15 +26,22 @@ public:
     void resetMarks();
 
     /// @brief Mark all connected entries
-    /// @param point origin point
-    void markIsle(const glm::ivec2& point);
+    /// @param origin origin point
+    void markIsle(const glm::ivec2& origin);
 
     /// @brief Erase all non-marked isles
     /// @return erased entries positions
     std::vector<glm::ivec2> sweep();
 
-    /// @brief Expand all confirmed entries with specified level
+    /// @brief Attempt to upgrade all confirmed entries with specified level
     /// @param level target entries level
     /// @return All upgraded entries positions 
-    std::vector<glm::ivec2> expand(int level);
+    std::vector<glm::ivec2> upgrade();
+    
+    /// @brief Create entry if does not exist
+    /// @param origin entry position
+    /// @return true if new entry has been created
+    bool createEntry(const glm::ivec2& origin);
+
+    void getLevels(unsigned char* out, int width, int height, int ox, int oy) const;
 };

test/world/generator/SurroundMap.cpp

@@ -3,5 +3,11 @@
 #include "world/generator/SurroundMap.hpp"
 
 TEST(SurroundMap, InitTest) {
+    int w = 8;
+    int h = 8;
+
     SurroundMap map;
+    map.createEntry({w/2, h/2});
+    map.createEntry({w/2+1, h/2+1});
+    EXPECT_EQ(map.upgrade().size(), 12);
 }