add generator param 'wide-structs-chunks-radius' & make caves more interesting

res/content/base/generators/demo.files/script.lua

@@ -31,21 +31,35 @@ end
 
 function place_structures_wide(x, z, w, d, seed, chunk_height)
     local placements = {}
-    if math.random() < 0.1 then -- generate caves
-        local sy = math.random() * (chunk_height / 6) + 80
-        local ey = math.max(1, sy - chunk_height / 4)
-        local my = (sy + ey) / 2 + math.random() * 24 - 12
-        local sx = x + math.random() * 60 - 30
-        local ex = x + math.random() * 60 - 30
-        local mx = (sx + ex) / 2 + math.random() * 32 - 16
-        local sz = z + math.random() * 60 - 30
-        local ez = z + math.random() * 60 - 30
-        local mz = (sz + ez) / 2 + math.random() * 32 - 16
+    if math.random() < 0.3 then -- generate caves
+        local sx = x + math.random() * 10 - 5
+        local sy = math.random() * (chunk_height / 6) + 40
+        local sz = z + math.random() * 10 - 5
+
+        local dir = math.random() * math.pi * 2
+        local dir_inertia = (math.random() - 0.5) * 2
+        local elevation = -sy / (chunk_height / 6)
         local width = math.random()*3+2
-        table.insert(placements, 
-            {":line", 0, {sx, sy, sz}, {mx, my, mz}, width})
-        table.insert(placements, 
-            {":line", 0, {mx, my, mz}, {ex, ey, ez}, width})
+
+        for i=1,10 do
+            local dx = math.sin(dir) * 10
+            local dz = -math.cos(dir) * 10
+
+            local ex = sx + dx
+            local ey = sy + elevation
+            local ez = sz + dz
+
+            table.insert(placements, 
+                {":line", 0, {sx, sy, sz}, {ex, ey, ez}, width})
+
+            sx = ex
+            sy = ey
+            sz = ez
+            
+            dir_inertia = dir_inertia * 0.8 + (math.random() - 0.5) * math.pow(math.random(), 2) * 8
+            elevation = elevation * 0.9 + (math.random() - 0.4) * (1.0-math.pow(math.random(), 4)) * 8
+            dir = dir + dir_inertia
+        end
     end
     return placements
 end

src/content/loading/GeneratorLoader.cpp

@@ -196,6 +196,7 @@ void ContentLoader::loadGenerator(
     map.at("biome-bpd").get(def.biomesBPD);
     map.at("heights-bpd").get(def.heightsBPD);
     map.at("sea_level").get(def.seaLevel);
+    map.at("wide-structs-chunks-radius").get(def.wideStructsChunksRadius);
 
     auto folder = generatorsDir / fs::u8path(name + ".files");
     auto scriptFile = folder / fs::u8path("script.lua");

src/world/generator/GeneratorDef.hpp

@@ -204,6 +204,10 @@ struct GeneratorDef {
     /// @brief Heightmap blocks per dot
     uint heightsBPD = 4;
 
+    /// @brief Number of chunks must be generated before and after wide
+    /// structures placement triggered
+    uint wideStructsChunksRadius = 3;
+
     std::unordered_map<std::string, size_t> structuresIndices;
     std::vector<std::unique_ptr<VoxelStructure>> structures;
     std::vector<Biome> biomes;

src/world/generator/WorldGenerator.cpp

@@ -17,16 +17,20 @@
 static debug::Logger logger("world-generator");
 
 static inline constexpr uint MAX_PARAMETERS = 4;
-static inline constexpr uint MAX_CHUNK_PROTOTYPE_LEVELS = 10;
+static inline constexpr uint BASIC_PROTOTYPE_LAYERS = 5;
 
 WorldGenerator::WorldGenerator(
     const GeneratorDef& def, const Content* content, uint64_t seed
 )
     : def(def), 
       content(content), 
-      seed(seed), 
-      surroundMap(0, MAX_CHUNK_PROTOTYPE_LEVELS) 
+      seed(seed),
+      surroundMap(0, BASIC_PROTOTYPE_LAYERS + def.wideStructsChunksRadius * 2)
 {
+    uint levels = BASIC_PROTOTYPE_LAYERS + def.wideStructsChunksRadius * 2;
+
+    surroundMap = SurroundMap(0, levels);
+    logger.info() << "total number of prototype levels is " << levels;
     surroundMap.setOutCallback([this](int const x, int const z, int8_t) {
         const auto& found = prototypes.find({x, z});
         if (found == prototypes.end()) {
@@ -41,16 +45,17 @@ WorldGenerator::WorldGenerator(
         }
         prototypes[{x, z}] = generatePrototype(x, z);
     });
-    surroundMap.setLevelCallback(4, [this](int const x, int const z) {
+    surroundMap.setLevelCallback(def.wideStructsChunksRadius + 1, 
+    [this](int const x, int const z) {
         generateStructuresWide(requirePrototype(x, z), x, z);
     });
-    surroundMap.setLevelCallback(7, [this](int const x, int const z) {
+    surroundMap.setLevelCallback(levels-3, [this](int const x, int const z) {
         generateBiomes(requirePrototype(x, z), x, z);
     });
-    surroundMap.setLevelCallback(8, [this](int const x, int const z) {
+    surroundMap.setLevelCallback(levels-2, [this](int const x, int const z) {
         generateHeightmap(requirePrototype(x, z), x, z);
     });
-    surroundMap.setLevelCallback(9, [this](int const x, int const z) {
+    surroundMap.setLevelCallback(levels-1, [this](int const x, int const z) {
         generateStructures(requirePrototype(x, z), x, z);
     });
     for (int i = 0; i < def.structures.size(); i++) {
@@ -180,8 +185,10 @@ void WorldGenerator::placeLine(const LinePlacement& line) {
     int czb = floordiv(aabb.b.z, CHUNK_D);
     for (int cz = cza; cz <= czb; cz++) {
         for (int cx = cxa; cx <= cxb; cx++) {
-            auto& otherPrototype = requirePrototype(cx, cz);
-            otherPrototype.lines.push_back(line);
+            const auto& found = prototypes.find({cx, cz});
+            if (found != prototypes.end()) {
+                found->second->lines.push_back(line);
+            }
         }
     }
 }