From 8e931d8f538f5c822758cb05242a46e724a4064a Mon Sep 17 00:00:00 2001
From: MihailRis <mexaruc@gmail.com>
Date: Tue, 25 Jun 2024 16:35:06 +0300
Subject: [PATCH] add entity library

---
 res/content/base/scripts/hud.lua      |  5 ++++-
 src/logic/scripting/lua/libentity.cpp | 28 +++++++++++++++++++++++++--
 src/logic/scripting/lua/lua_util.hpp  | 10 ++++++++++
 src/objects/Entities.cpp              | 10 +++++-----
 src/objects/Entities.hpp              | 21 +++++++++++++++++---
 5 files changed, 63 insertions(+), 11 deletions(-)

diff --git a/res/content/base/scripts/hud.lua b/res/content/base/scripts/hud.lua
index 8e605bb8..e33f5a0f 100644
--- a/res/content/base/scripts/hud.lua
+++ b/res/content/base/scripts/hud.lua
@@ -1,5 +1,8 @@
 function on_hud_open()
     input.add_callback("player.drop", function ()
-        entity.test()
+        local pid = hud.get_player()
+        local pvel = {player.get_vel(pid)}
+        local eid = entity.test()
+        entity.set_vel(eid, pvel)
     end)
 end
diff --git a/src/logic/scripting/lua/libentity.cpp b/src/logic/scripting/lua/libentity.cpp
index 5ab0181b..859364a8 100644
--- a/src/logic/scripting/lua/libentity.cpp
+++ b/src/logic/scripting/lua/libentity.cpp
@@ -8,19 +8,43 @@
 #include "../../../window/Camera.hpp"
 #include "../../../frontend/hud.hpp"
 
+#include <optional>
+
 namespace scripting {
     extern Hud* hud;
 }
 using namespace scripting;
 
+static std::optional<Entity> get_entity(lua::State* L, int idx) {
+    auto id = lua::tointeger(L, idx);
+    auto level = controller->getLevel();
+    return level->entities->get(id);
+}
+
 static int l_test(lua::State* L) {
     auto level = controller->getLevel();
     auto player = hud->getPlayer();
-    level->entities->drop(player->camera->position, player->camera->front*8.0f+glm::vec3(0, 2, 0)+player->hitbox->velocity);
-    return 0;        
+    auto id = level->entities->drop(player->camera->position);
+    return lua::pushinteger(L, id);
+}
+
+static int l_get_vel(lua::State* L) {
+    if (auto entity = get_entity(L, 1)) {
+        return lua::pushvec3_arr(L, entity->getHitbox().velocity);
+    }
+    return 0;
+}
+
+static int l_set_vel(lua::State* L) {
+    if (auto entity = get_entity(L, 1)) {
+        entity->getHitbox().velocity = lua::tovec3(L, 2);
+    }
+    return 0;
 }
 
 const luaL_Reg entitylib [] = {
     {"test", lua::wrap<l_test>},
+    {"get_vel", lua::wrap<l_get_vel>},
+    {"set_vel", lua::wrap<l_set_vel>},
     {NULL, NULL}
 };
diff --git a/src/logic/scripting/lua/lua_util.hpp b/src/logic/scripting/lua/lua_util.hpp
index a774d283..2095526b 100644
--- a/src/logic/scripting/lua/lua_util.hpp
+++ b/src/logic/scripting/lua/lua_util.hpp
@@ -379,6 +379,16 @@ namespace lua {
         pop(L);
         return glm::vec4(x, y, z, w);
     }
+    inline glm::vec3 tovec3_stack(lua::State* L, int idx) { 
+        return glm::vec3(
+            tonumber(L, idx), tonumber(L, idx+1), tonumber(L, idx+2)
+        );
+    }
+    inline glm::vec4 tovec4_stack(lua::State* L, int idx) { 
+        return glm::vec4(
+            tonumber(L, idx), tonumber(L, idx+1), tonumber(L, idx+2), tonumber(L, idx+3)
+        );
+    }
     inline glm::mat4 tomat4(lua::State* L, int idx) {
         pushvalue(L, idx);
         if (!istable(L, idx) || objlen(L, idx) < 16) {
diff --git a/src/objects/Entities.cpp b/src/objects/Entities.cpp
index fd4fe76c..a608dded 100644
--- a/src/objects/Entities.cpp
+++ b/src/objects/Entities.cpp
@@ -20,16 +20,16 @@ void Transform::refresh() {
 Entities::Entities(Level* level) : level(level) {
 }
 
-void Entities::drop(glm::vec3 pos, glm::vec3 vel) {
+entityid_t Entities::drop(glm::vec3 pos) {
     auto entity = registry.create();
     glm::vec3 size(1);
-    registry.emplace<EntityId>(entity, static_cast<entityid_t>(1));
+    auto id = nextID++;
+    registry.emplace<EntityId>(entity, static_cast<entityid_t>(id));
     registry.emplace<Transform>(entity, pos, size/4.0f, glm::mat3(1.0f));
     registry.emplace<Hitbox>(entity, pos, 
         glm::vec3(size.x*0.2f, size.y*0.5f, size.z*0.2f));
-
-    auto& hitbox = registry.get<Hitbox>(entity);
-    hitbox.velocity = vel;
+    entities[id] = entity;
+    return id;
 }
 
 void Entities::updatePhysics(float delta){
diff --git a/src/objects/Entities.hpp b/src/objects/Entities.hpp
index 8efc7197..f51f59bb 100644
--- a/src/objects/Entities.hpp
+++ b/src/objects/Entities.hpp
@@ -2,7 +2,9 @@
 #define OBJECTS_ENTITIES_HPP_
 
 #include "../typedefs.hpp"
+#include "../physics/Hitbox.hpp"
 
+#include <optional>
 #include <glm/glm.hpp>
 #include <unordered_map>
 #include <entt/entity/registry.hpp>
@@ -28,9 +30,9 @@ class Rig;
 
 class Entity {
     entt::registry& registry;
-    entt::entity entity;
+    const entt::entity entity;
 public:
-    Entity(entt::registry& registry, entt::entity entity)
+    Entity(entt::registry& registry, const entt::entity entity)
     : registry(registry), entity(entity) {}
 
     bool isValid() const {
@@ -41,6 +43,10 @@ public:
         return registry.get<Transform>(entity);
     }
 
+    Hitbox& getHitbox() const {
+        return registry.get<Hitbox>(entity);
+    }
+
     entityid_t getUID() const {
         return registry.get<EntityId>(entity).uid;
     }
@@ -50,12 +56,21 @@ class Entities {
     entt::registry registry;
     Level* level;
     std::unordered_map<entityid_t, entt::entity> entities;
+    entityid_t nextID = 1;
 public:
     Entities(Level* level);
     void updatePhysics(float delta);
     void render(Assets* assets, ModelBatch& batch, Frustum& frustum);
 
-    void drop(glm::vec3 pos, glm::vec3 vel);
+    entityid_t drop(glm::vec3 pos);
+
+    std::optional<Entity> get(entityid_t id) {
+        const auto& found = entities.find(id);
+        if (found != entities.end()) {
+            return Entity(registry, found->second);
+        }
+        return std::nullopt;
+    }
 };
 
 #endif // OBJECTS_ENTITIES_HPP_