From 50c714692af86e2d16015004f9c48dd223ad9fe4 Mon Sep 17 00:00:00 2001
From: MihailRis <mexaruc@gmail.com>
Date: Sun, 30 Jun 2024 00:32:02 +0300
Subject: [PATCH] add entity event: on_fall

---
 res/content/base/scripts/drop.lua | 22 +++++++++++++++++-----
 src/logic/scripting/scripting.cpp | 15 +++++++++++++--
 src/logic/scripting/scripting.hpp |  3 ++-
 src/objects/Entities.cpp          |  8 ++++++--
 src/objects/Entities.hpp          |  1 +
 5 files changed, 39 insertions(+), 10 deletions(-)

diff --git a/res/content/base/scripts/drop.lua b/res/content/base/scripts/drop.lua
index dbdace91..b228ec59 100644
--- a/res/content/base/scripts/drop.lua
+++ b/res/content/base/scripts/drop.lua
@@ -1,11 +1,23 @@
 inair = true
-function on_grounded()
+
+function on_grounded(force)
     entity.transform:set_rot(mat4.rotate({0, 1, 0}, math.random()*360))
     inair = false
 end
 
-function on_update()
-    if inair then
-        entity.transform:set_rot(mat4.rotate(entity.transform:get_rot(), {0, 1, 0}, math.random()*32))
-    end
+function on_fall()
+    inair = true
+end
+
+function on_update()
+    local tsf = entity.transform
+    local body = entity.rigidbody
+    if inair then
+        tsf:set_rot(mat4.rotate(tsf:get_rot(), {0, 1, 0}, math.random()*12))
+        tsf:set_rot(mat4.rotate(tsf:get_rot(), {0, 0, 1}, math.random()*12))
+    end
+    local dir = vec3.sub({player.get_pos(hud.get_player())}, tsf:get_pos())
+    vec3.normalize(dir, dir)
+    vec3.mul(dir, time.delta()*50.0, dir)
+    --body:set_vel(vec3.add(rigidbody:get_vel(), dir))
 end
diff --git a/src/logic/scripting/scripting.cpp b/src/logic/scripting/scripting.cpp
index cc50014b..720e2083 100644
--- a/src/logic/scripting/scripting.cpp
+++ b/src/logic/scripting/scripting.cpp
@@ -271,6 +271,7 @@ scriptenv scripting::on_entity_spawn(const EntityDef& def, entityid_t eid, entit
 
     lua::pushenv(L, *entityenv);
     funcsset.on_grounded = lua::hasfield(L, "on_grounded");
+    funcsset.on_fall = lua::hasfield(L, "on_fall");
     funcsset.on_despawn = lua::hasfield(L, "on_despawn");
     lua::pop(L, 2);
     return entityenv;
@@ -306,10 +307,20 @@ bool scripting::on_entity_despawn(const EntityDef& def, const Entity& entity) {
     return true;
 }
 
-bool scripting::on_entity_grounded(const EntityDef& def, const Entity& entity) {
+bool scripting::on_entity_grounded(const Entity& entity, float force) {
     const auto& script = entity.getScripting();
     if (script.funcsset.on_grounded) {
-        return process_entity_callback(script.env, "on_grounded", nullptr);
+        return process_entity_callback(script.env, "on_grounded", [force](auto L){
+            return lua::pushnumber(L, force);
+        });
+    }
+    return true;
+}
+
+bool scripting::on_entity_fall(const Entity& entity) {
+    const auto& script = entity.getScripting();
+    if (script.funcsset.on_fall) {
+        return process_entity_callback(script.env, "on_fall", nullptr);
     }
     return true;
 }
diff --git a/src/logic/scripting/scripting.hpp b/src/logic/scripting/scripting.hpp
index 98b9b9a2..a46d7500 100644
--- a/src/logic/scripting/scripting.hpp
+++ b/src/logic/scripting/scripting.hpp
@@ -78,7 +78,8 @@ namespace scripting {
 
     scriptenv on_entity_spawn(const EntityDef& def, entityid_t eid, entity_funcs_set&);
     bool on_entity_despawn(const EntityDef& def, const Entity& entity);
-    bool on_entity_grounded(const EntityDef& def, const Entity& entity);
+    bool on_entity_grounded(const Entity& entity, float force);
+    bool on_entity_fall(const Entity& entity);
     void on_entities_update();
 
     /// @brief Called on UI view show
diff --git a/src/objects/Entities.cpp b/src/objects/Entities.cpp
index 1d1fc214..52f914a6 100644
--- a/src/objects/Entities.cpp
+++ b/src/objects/Entities.cpp
@@ -67,6 +67,7 @@ void Entities::updatePhysics(float delta){
             continue;
         }
         auto& hitbox = rigidbody.hitbox;
+        auto prevVel = hitbox.velocity;
         bool grounded = hitbox.grounded;
         physics->step(
             level->chunks.get(),
@@ -77,11 +78,14 @@ void Entities::updatePhysics(float delta){
             1.0f,
             true
         );
-        hitbox.linearDamping = hitbox.grounded * 12;
+        hitbox.linearDamping = hitbox.grounded * 24;
         transform.pos = hitbox.position;
         //transform.rot = glm::rotate(glm::mat4(transform.rot), delta, glm::vec3(0, 1, 0));
         if (hitbox.grounded && !grounded) {
-            scripting::on_entity_grounded(eid.def, *get(eid.uid));
+            scripting::on_entity_grounded(*get(eid.uid), glm::length(prevVel-hitbox.velocity));
+        }
+        if (!hitbox.grounded && grounded) {
+            scripting::on_entity_fall(*get(eid.uid));
         }
     }
 }
diff --git a/src/objects/Entities.hpp b/src/objects/Entities.hpp
index 52cdcbde..80bf7e27 100644
--- a/src/objects/Entities.hpp
+++ b/src/objects/Entities.hpp
@@ -13,6 +13,7 @@ struct entity_funcs_set {
     bool init : 1;
     bool on_despawn : 1;
     bool on_grounded : 1;
+    bool on_fall : 1;
 };
 
 struct EntityDef;