From 95cf451cc808cf1206c9f749dd5a2769e3ca1186 Mon Sep 17 00:00:00 2001
From: MihailRis <mexaruc@gmail.com>
Date: Wed, 14 Aug 2024 17:12:12 +0300
Subject: [PATCH] add GeneratorScript

---
 res/generators/{default.lua => flat.lua}      | 20 +++------
 src/content/ContentLoader.cpp                 | 32 ++++++++++++--
 src/content/ContentLoader.hpp                 |  4 ++
 src/files/util.hpp                            | 16 +++++++
 src/logic/scripting/lua/lua_custom_types.hpp  | 36 +++++++++-------
 src/logic/scripting/lua/lua_engine.cpp        |  2 +-
 .../scripting/lua/lua_type_heightmap.cpp      | 31 ++++++-------
 src/logic/scripting/lua/lua_util.hpp          |  8 ++++
 src/logic/scripting/scripting.cpp             | 43 ++++++++++++++++++-
 src/logic/scripting/scripting.hpp             |  6 +++
 src/maths/Heightmap.hpp                       | 34 +++++++++++++++
 src/world/generator/GeneratorDef.hpp          | 15 ++++++-
 12 files changed, 196 insertions(+), 51 deletions(-)
 rename res/generators/{default.lua => flat.lua} (60%)
 create mode 100644 src/files/util.hpp
 create mode 100644 src/maths/Heightmap.hpp

diff --git a/res/generators/default.lua b/res/generators/flat.lua
similarity index 60%
rename from res/generators/default.lua
rename to res/generators/flat.lua
index defe9131..2d8c47b4 100644
--- a/res/generators/default.lua
+++ b/res/generators/flat.lua
@@ -1,24 +1,21 @@
-local W = 256
-local H = 256
-
-function generate_heightmap(x, y)
-    local umap = Heightmap(W, H)
-    local vmap = Heightmap(W, H)
+function generate_heightmap(x, y, w, h)
+    local umap = Heightmap(w, h)
+    local vmap = Heightmap(w, h)
     umap:noise({x+521, y+73}, 0.05, 1, 20.8)
     umap:noise({x+51, y+75}, 0.05, 1, 21.8)
-    umap:noise({x+521, y+70}, 0.1, 3, 35.8)
+    vmap:noise({x+521, y+70}, 0.1, 3, 35.8)
     vmap:noise({x+95, y+246}, 0.15, 3, 35.8)
 
-    local bmap = Heightmap(W, H)
+    local bmap = Heightmap(w, h)
     bmap:noise({x+3, y+6}, 0.1, 1, 3)
     
-    local map = Heightmap(W, H)
+    local map = Heightmap(w, h)
     map:noise({x, y}, 0.06, 5, 0.2, umap, vmap)
     map:noise({x, y}, 0.12, 6, 0.5, umap, vmap)
     map:mul(bmap)
     map:mul(0.7)
 
-    local rivermap = Heightmap(W, H)
+    local rivermap = Heightmap(w, h)
     rivermap:noise({x+21, y+12}, 0.1, 3)
     rivermap:abs()
     rivermap:min(0.5)
@@ -31,6 +28,3 @@ function generate_heightmap(x, y)
 
     return map
 end
-
-local map = generate_heightmap(0, 0)
-map:dump("heightmap.png")
diff --git a/src/content/ContentLoader.cpp b/src/content/ContentLoader.cpp
index 96a5eadf..fef55cdb 100644
--- a/src/content/ContentLoader.cpp
+++ b/src/content/ContentLoader.cpp
@@ -376,6 +376,18 @@ void ContentLoader::loadEntity(
     if (fs::exists(configFile)) loadEntity(def, full, configFile);
 }
 
+
+void ContentLoader::loadGenerator(
+    GeneratorDef& def, const std::string& full, const std::string& name
+) {
+    auto folder = pack->folder;
+    auto generatorFile = folder / fs::path("generators/" + name + ".lua");
+    if (!fs::exists(generatorFile)) {
+        return;
+    }
+    def.script = scripting::load_generator(generatorFile);
+}
+
 void ContentLoader::loadBlock(
     Block& def, const std::string& full, const std::string& name
 ) {
@@ -450,6 +462,21 @@ void ContentLoader::load() {
         );
     }
 
+    fs::path generatorsDir = folder / fs::u8path("generators");
+    if (fs::is_directory(generatorsDir)) {
+        for (const auto& entry : fs::directory_iterator(generatorsDir)) {
+            const auto& file = entry.path();
+
+            std::string name = file.stem().u8string();
+            auto [packid, full, filename] =
+                create_unit_id(pack->id, file.stem().u8string());
+
+            auto& def = builder.generators.create(full);
+
+            loadGenerator(def, full, name);
+        }
+    }
+
     if (!fs::is_regular_file(pack->getContentFile())) return;
 
     auto root = files::read_json(pack->getContentFile());
@@ -486,7 +513,6 @@ void ContentLoader::load() {
     if (auto entitiesarr = root->list("entities")) {
         for (size_t i = 0; i < entitiesarr->size(); i++) {
             std::string name = entitiesarr->str(i);
-
             auto [packid, full, filename] = create_unit_id(pack->id, name);
 
             auto& def = builder.entities.create(full);
@@ -499,7 +525,7 @@ void ContentLoader::load() {
     fs::path materialsDir = folder / fs::u8path("block_materials");
     if (fs::is_directory(materialsDir)) {
         for (const auto& entry : fs::directory_iterator(materialsDir)) {
-            const fs::path& file = entry.path();
+            const auto& file = entry.path();
             auto [packid, full, filename] =
                 create_unit_id(pack->id, file.stem().u8string());
             loadBlockMaterial(
@@ -512,7 +538,7 @@ void ContentLoader::load() {
     fs::path skeletonsDir = folder / fs::u8path("skeletons");
     if (fs::is_directory(skeletonsDir)) {
         for (const auto& entry : fs::directory_iterator(skeletonsDir)) {
-            const fs::path& file = entry.path();
+            const auto& file = entry.path();
             std::string name = pack->id + ":" + file.stem().u8string();
             std::string text = files::read_string(file);
             builder.add(
diff --git a/src/content/ContentLoader.hpp b/src/content/ContentLoader.hpp
index 0673a96d..0a65f640 100644
--- a/src/content/ContentLoader.hpp
+++ b/src/content/ContentLoader.hpp
@@ -13,6 +13,7 @@ struct BlockMaterial;
 struct ItemDef;
 struct EntityDef;
 struct ContentPack;
+struct GeneratorDef;
 
 class ContentBuilder;
 class ContentPackRuntime;
@@ -39,6 +40,9 @@ class ContentLoader {
     void loadEntity(
         EntityDef& def, const std::string& full, const std::string& name
     );
+    void loadGenerator(
+        GeneratorDef& def, const std::string& full, const std::string& name
+    );
 
     static void loadCustomBlockModel(Block& def, dynamic::Map* primitives);
     static void loadBlockMaterial(BlockMaterial& def, const fs::path& file);
diff --git a/src/files/util.hpp b/src/files/util.hpp
new file mode 100644
index 00000000..5967299e
--- /dev/null
+++ b/src/files/util.hpp
@@ -0,0 +1,16 @@
+#pragma once
+
+#include <string>
+#include <stdexcept>
+
+namespace files {
+    inline bool is_valid_name(std::string_view name) {
+        static std::string illegalChars = "\\/%?!<>:; ";
+        for (char c : illegalChars) {
+            if (name.find(c) != std::string::npos) {
+                return false;
+            }
+        }
+        return !name.empty();
+    }
+}
diff --git a/src/logic/scripting/lua/lua_custom_types.hpp b/src/logic/scripting/lua/lua_custom_types.hpp
index 885052ce..951d52cf 100644
--- a/src/logic/scripting/lua/lua_custom_types.hpp
+++ b/src/logic/scripting/lua/lua_custom_types.hpp
@@ -4,6 +4,7 @@
 #include <vector>
 
 #include "lua_commons.hpp"
+#include "maths/Heightmap.hpp"
 
 namespace lua {
     class Userdata {
@@ -27,37 +28,42 @@ namespace lua {
         }
 
         static int createMetatable(lua::State*);
-        inline static std::string TYPENAME = "bytearray";
+        inline static std::string TYPENAME = "Bytearray";
     };
 
-    class Heightmap : public Userdata {
-        std::vector<float> buffer;
-        uint width, height;
+    class LuaHeightmap : public Userdata {
+        std::shared_ptr<Heightmap> map;
     public:
-        Heightmap(uint width, uint height);
-        virtual ~Heightmap();
+        LuaHeightmap(uint width, uint height) 
+        : map(std::make_shared<Heightmap>(width, height)) {}
+
+        virtual ~LuaHeightmap() = default;
 
         uint getWidth() const {
-            return width;
+            return map->getWidth();
         }
 
         uint getHeight() const {
-            return height;
+            return map->getHeight();
+        }
+
+        float* getValues() {
+            return map->getValues();
+        }
+
+        const float* getValues() const {
+            return map->getValues();
         }
 
         const std::string& getTypeName() const override {
             return TYPENAME;
         }
 
-        float* getValues() {
-            return buffer.data();
-        }
-
-        const float* getValues() const {
-            return buffer.data();
+        std::shared_ptr<Heightmap> getHeightmap() const {
+            return map;
         }
 
         static int createMetatable(lua::State*);
-        inline static std::string TYPENAME = "heightmap";
+        inline static std::string TYPENAME = "Heightmap";
     };
 }
diff --git a/src/logic/scripting/lua/lua_engine.cpp b/src/logic/scripting/lua/lua_engine.cpp
index 8008517a..879ec4c6 100644
--- a/src/logic/scripting/lua/lua_engine.cpp
+++ b/src/logic/scripting/lua/lua_engine.cpp
@@ -97,7 +97,7 @@ void lua::initialize() {
     initialize_libs_extends(L);
 
     newusertype<Bytearray, Bytearray::createMetatable>(L, "Bytearray");
-    newusertype<Heightmap, Heightmap::createMetatable>(L, "Heightmap");
+    newusertype<LuaHeightmap, LuaHeightmap::createMetatable>(L, "Heightmap");
 }
 
 void lua::finalize() {
diff --git a/src/logic/scripting/lua/lua_type_heightmap.cpp b/src/logic/scripting/lua/lua_type_heightmap.cpp
index ecbdc1bf..357011f3 100644
--- a/src/logic/scripting/lua/lua_type_heightmap.cpp
+++ b/src/logic/scripting/lua/lua_type_heightmap.cpp
@@ -8,6 +8,7 @@
 #include "util/functional_util.hpp"
 #include "maths/FastNoiseLite.h"
 #include "coders/png.hpp"
+#include "files/util.hpp"
 #include "graphics/core/ImageData.hpp"
 #include "lua_util.hpp"
 
@@ -15,16 +16,12 @@ using namespace lua;
 
 static fnl_state noise = fnlCreateState();
 
-Heightmap::Heightmap(uint width, uint height) : width(width), height(height) {
-    buffer.resize(width*height);
-}
-
-Heightmap::~Heightmap() {
-}
-
 static int l_dump(lua::State* L) {
-    if (auto heightmap = touserdata<Heightmap>(L, 1)) {
+    if (auto heightmap = touserdata<LuaHeightmap>(L, 1)) {
         auto filename = tostring(L, 2);
+        if (!files::is_valid_name(filename)) {
+            throw std::runtime_error("invalid file name");
+        }
         uint w = heightmap->getWidth();
         uint h = heightmap->getHeight();
         ImageData image(ImageFormat::rgb888, w, h);
@@ -46,7 +43,7 @@ static int l_dump(lua::State* L) {
 }
 
 static int l_noise(lua::State* L) {
-    if (auto heightmap = touserdata<Heightmap>(L, 1)) {
+    if (auto heightmap = touserdata<LuaHeightmap>(L, 1)) {
         uint w = heightmap->getWidth();
         uint h = heightmap->getHeight();
         auto heights = heightmap->getValues();
@@ -62,13 +59,13 @@ static int l_noise(lua::State* L) {
         if (gettop(L) > 4) {
             multiplier = tonumber(L, 5);
         }
-        const Heightmap* shiftMapX = nullptr;
-        const Heightmap* shiftMapY = nullptr;
+        const LuaHeightmap* shiftMapX = nullptr;
+        const LuaHeightmap* shiftMapY = nullptr;
         if (gettop(L) > 5) {
-            shiftMapX = touserdata<Heightmap>(L, 6);
+            shiftMapX = touserdata<LuaHeightmap>(L, 6);
         }
         if (gettop(L) > 6) {
-            shiftMapY = touserdata<Heightmap>(L, 7);
+            shiftMapY = touserdata<LuaHeightmap>(L, 7);
         }
         for (uint y = 0; y < h; y++) {
             for (uint x = 0; x < w; x++) {
@@ -159,13 +156,13 @@ static int l_meta_meta_call(lua::State* L) {
     if (width <= 0 || height <= 0) {
         throw std::runtime_error("width and height must be greather than 0");
     }
-    return newuserdata<Heightmap>(
+    return newuserdata<LuaHeightmap>(
         L, static_cast<uint>(width), static_cast<uint>(height)
     );
 }
 
 static int l_meta_index(lua::State* L) {
-    auto map = touserdata<Heightmap>(L, 1);
+    auto map = touserdata<LuaHeightmap>(L, 1);
     if (map == nullptr) {
         return 0;
     }
@@ -186,7 +183,7 @@ static int l_meta_index(lua::State* L) {
 }
 
 static int l_meta_tostring(lua::State* L) {
-    auto map = touserdata<Heightmap>(L, 1);
+    auto map = touserdata<LuaHeightmap>(L, 1);
     if (map == nullptr) {
         return 0;
     }
@@ -201,7 +198,7 @@ static int l_meta_tostring(lua::State* L) {
     );
 }
 
-int Heightmap::createMetatable(lua::State* L) {
+int LuaHeightmap::createMetatable(lua::State* L) {
     createtable(L, 0, 2);
     pushcfunction(L, lua::wrap<l_meta_tostring>);
     setfield(L, "__tostring");
diff --git a/src/logic/scripting/lua/lua_util.hpp b/src/logic/scripting/lua/lua_util.hpp
index 0822e5bc..ce77c429 100644
--- a/src/logic/scripting/lua/lua_util.hpp
+++ b/src/logic/scripting/lua/lua_util.hpp
@@ -153,6 +153,14 @@ namespace lua {
         return 3;
     }
 
+    template<int n>
+    inline int pushivec_stack(lua::State* L, glm::vec<n, int> vec) {
+        for (int i = 0; i < n; i++) {
+            pushinteger(L, vec[i]);
+        }
+        return n;
+    }
+
     inline int pushivec3_stack(lua::State* L, glm::ivec3 vec) {
         pushinteger(L, vec.x);
         pushinteger(L, vec.y);
diff --git a/src/logic/scripting/scripting.cpp b/src/logic/scripting/scripting.cpp
index aeedc1d9..03267e20 100644
--- a/src/logic/scripting/scripting.cpp
+++ b/src/logic/scripting/scripting.cpp
@@ -14,6 +14,9 @@
 #include "items/ItemDef.hpp"
 #include "logic/BlocksController.hpp"
 #include "logic/LevelController.hpp"
+#include "lua/lua_engine.hpp"
+#include "lua/lua_custom_types.hpp"
+#include "maths/Heightmap.hpp"
 #include "objects/Entities.hpp"
 #include "objects/EntityDef.hpp"
 #include "objects/Player.hpp"
@@ -21,7 +24,7 @@
 #include "util/timeutil.hpp"
 #include "voxels/Block.hpp"
 #include "world/Level.hpp"
-#include "lua/lua_engine.hpp"
+#include "world/generator/GeneratorDef.hpp"
 
 using namespace scripting;
 
@@ -62,6 +65,15 @@ void scripting::initialize(Engine* engine) {
     return std::make_shared<int>(0);
 }
 
+[[nodiscard]] scriptenv scripting::create_environment() {
+    auto L = lua::get_main_thread();
+    int id = lua::create_environment(L, 0);
+    return std::shared_ptr<int>(new int(id), [=](int* id) { //-V508
+        lua::removeEnvironment(L, *id);
+        delete id;
+    });
+}
+
 [[nodiscard]] scriptenv scripting::create_pack_environment(
     const ContentPack& pack
 ) {
@@ -672,6 +684,35 @@ void scripting::load_entity_component(
     lua::store_in(L, lua::CHUNKS_TABLE, name);
 }
 
+class LuaGeneratorScript : public GeneratorScript {
+    scriptenv env;
+public:
+    LuaGeneratorScript(scriptenv env) : env(std::move(env)) {}
+
+    std::shared_ptr<Heightmap> generateHeightmap(
+        const glm::ivec2& offset, const glm::ivec2& size
+    ) override {
+        auto L = lua::get_main_thread();
+        lua::pushenv(L, *env);
+        if (lua::getfield(L, "generate_heightmap")) {
+            lua::pushivec_stack(L, offset);
+            lua::pushivec_stack(L, size);
+            if (lua::call_nothrow(L, 4)) {
+                return lua::touserdata<lua::LuaHeightmap>(L, -1)->getHeightmap();
+            }
+        }
+        return std::make_shared<Heightmap>(size.x, size.y);
+    }
+};
+
+std::unique_ptr<GeneratorScript> scripting::load_generator(
+    const fs::path& file
+) {
+    auto env = create_environment();
+    load_script(*env, "generator", file);
+    return std::make_unique<LuaGeneratorScript>(std::move(env));
+}
+
 void scripting::load_world_script(
     const scriptenv& senv,
     const std::string& prefix,
diff --git a/src/logic/scripting/scripting.hpp b/src/logic/scripting/scripting.hpp
index 94723f05..85fd8323 100644
--- a/src/logic/scripting/scripting.hpp
+++ b/src/logic/scripting/scripting.hpp
@@ -32,6 +32,7 @@ class BlocksController;
 class LevelController;
 class Entity;
 struct EntityDef;
+class GeneratorScript;
 
 namespace scripting {
     extern Engine* engine;
@@ -50,6 +51,7 @@ namespace scripting {
 
     scriptenv get_root_environment();
     scriptenv create_pack_environment(const ContentPack& pack);
+    scriptenv create_environment();
     scriptenv create_doc_environment(
         const scriptenv& parent, const std::string& name
     );
@@ -144,6 +146,10 @@ namespace scripting {
 
     void load_entity_component(const std::string& name, const fs::path& file);
 
+    std::unique_ptr<GeneratorScript> load_generator(
+        const fs::path& file
+    );
+
     /// @brief Load package-specific world script
     /// @param env environment
     /// @param packid content-pack id
diff --git a/src/maths/Heightmap.hpp b/src/maths/Heightmap.hpp
new file mode 100644
index 00000000..cd125d36
--- /dev/null
+++ b/src/maths/Heightmap.hpp
@@ -0,0 +1,34 @@
+#pragma once
+
+#include <vector>
+#include <string>
+
+#include "typedefs.hpp"
+
+class Heightmap {
+    std::vector<float> buffer;
+    uint width, height;
+public:
+    Heightmap(uint width, uint height)
+        : width(width), height(height) {
+        buffer.resize(width*height);
+    }
+
+    ~Heightmap() = default;
+
+    uint getWidth() const {
+        return width;
+    }
+
+    uint getHeight() const {
+        return height;
+    }
+
+    float* getValues() {
+        return buffer.data();
+    }
+
+    const float* getValues() const {
+        return buffer.data();
+    }
+};
diff --git a/src/world/generator/GeneratorDef.hpp b/src/world/generator/GeneratorDef.hpp
index fa26787f..608d0749 100644
--- a/src/world/generator/GeneratorDef.hpp
+++ b/src/world/generator/GeneratorDef.hpp
@@ -1,10 +1,23 @@
 #pragma once
 
 #include <string>
+#include <glm/glm.hpp>
 
 #include "typedefs.hpp"
+#include "maths/Heightmap.hpp"
+
+class GeneratorScript {
+public:
+    virtual ~GeneratorScript() = default;
+
+    virtual std::shared_ptr<Heightmap> generateHeightmap(
+        const glm::ivec2& offset, const glm::ivec2& size) = 0;
+};
 
 struct GeneratorDef {
     std::string name;
-    scriptenv env;
+    std::unique_ptr<GeneratorScript> script;
+
+    GeneratorDef(std::string name) : name(std::move(name)) {}
+    GeneratorDef(const GeneratorDef&) = delete;
 };