From 8f66527e02b1cb7b81ac5fc154958fde935a2896 Mon Sep 17 00:00:00 2001
From: "Michael Cook (mackal)" <mcook@mackal.net>
Date: Tue, 6 Mar 2018 23:03:55 -0500
Subject: [PATCH] Add TryMoveAlong(distance, angle)

This will take a distance you would like to move and an EQ angle you
would like to move relative to current heading (so 0 is in front, 256
behind)

Exported to Lua as well
---
 zone/lua_mob.cpp   | 12 ++++++++++++
 zone/lua_mob.h     |  2 ++
 zone/mob.h         |  1 +
 zone/waypoints.cpp | 32 ++++++++++++++++++++++++++++++++
 4 files changed, 47 insertions(+)

diff --git a/zone/lua_mob.cpp b/zone/lua_mob.cpp
index bd5cddbcc..3793e6b9d 100644
--- a/zone/lua_mob.cpp
+++ b/zone/lua_mob.cpp
@@ -282,6 +282,16 @@ void Lua_Mob::GMMove(double x, double y, double z, double heading, bool send_upd
 	self->GMMove(static_cast<float>(x), static_cast<float>(y), static_cast<float>(z), static_cast<float>(heading), send_update);
 }
 
+void Lua_Mob::TryMoveAlong(float distance, float angle) {
+	Lua_Safe_Call_Void();
+	self->TryMoveAlong(distance, angle);
+}
+
+void Lua_Mob::TryMoveAlong(float distance, float angle, bool send) {
+	Lua_Safe_Call_Void();
+	self->TryMoveAlong(distance, angle, send);
+}
+
 bool Lua_Mob::HasProcs() {
 	Lua_Safe_Call_Bool();
 	return self->HasProcs();
@@ -2197,6 +2207,8 @@ luabind::scope lua_register_mob() {
 		.def("GMMove", (void(Lua_Mob::*)(double,double,double))&Lua_Mob::GMMove)
 		.def("GMMove", (void(Lua_Mob::*)(double,double,double,double))&Lua_Mob::GMMove)
 		.def("GMMove", (void(Lua_Mob::*)(double,double,double,double,bool))&Lua_Mob::GMMove)
+		.def("TryMoveAlong", (void(Lua_Mob::*)(float,float))&Lua_Mob::TryMoveAlong)
+		.def("TryMoveAlong", (void(Lua_Mob::*)(float,float,bool))&Lua_Mob::TryMoveAlong)
 		.def("HasProcs", &Lua_Mob::HasProcs)
 		.def("IsInvisible", (bool(Lua_Mob::*)(void))&Lua_Mob::IsInvisible)
 		.def("IsInvisible", (bool(Lua_Mob::*)(Lua_Mob))&Lua_Mob::IsInvisible)
diff --git a/zone/lua_mob.h b/zone/lua_mob.h
index 7aeb700e6..17dbc5c43 100644
--- a/zone/lua_mob.h
+++ b/zone/lua_mob.h
@@ -74,6 +74,8 @@ public:
 	void GMMove(double x, double y, double z);
 	void GMMove(double x, double y, double z, double heading);
 	void GMMove(double x, double y, double z, double heading, bool send_update);
+	void TryMoveAlong(float distance, float heading);
+	void TryMoveAlong(float distance, float heading, bool send);
 	bool HasProcs();
 	bool IsInvisible();
 	bool IsInvisible(Lua_Mob other);
diff --git a/zone/mob.h b/zone/mob.h
index 23c0004df..d19f4299c 100644
--- a/zone/mob.h
+++ b/zone/mob.h
@@ -578,6 +578,7 @@ public:
 	void SetFlyMode(uint8 flymode);
 	inline void Teleport(glm::vec3 NewPosition) { m_Position.x = NewPosition.x; m_Position.y = NewPosition.y;
 		m_Position.z = NewPosition.z; };
+	void TryMoveAlong(float distance, float angle, bool send = true);
 
 	//AI
 	static uint32 GetLevelCon(uint8 mylevel, uint8 iOtherLevel);
diff --git a/zone/waypoints.cpp b/zone/waypoints.cpp
index 45d199277..6cf74bb65 100644
--- a/zone/waypoints.cpp
+++ b/zone/waypoints.cpp
@@ -29,10 +29,13 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 #include "npc.h"
 #include "quest_parser_collection.h"
 #include "water_map.h"
+#include "fastmath.h"
 
 #include <math.h>
 #include <stdlib.h>
 
+extern FastMath g_Math;
+
 struct wp_distance
 {
 	float dist;
@@ -990,6 +993,35 @@ float Mob::GetZOffset() const {
 	return 0.2 * GetSize() * offset;
 }
 
+// This function will try to move the mob along the relative angle a set distance
+// if it can't be moved, it will lower the distance and try again
+// If we want to move on like say a spawn, we can pass send as false
+void Mob::TryMoveAlong(float distance, float angle, bool send)
+{
+	angle += GetHeading();
+	angle = FixHeading(angle);
+
+	glm::vec3 tmp_pos;
+	glm::vec3 new_pos = GetPosition();
+	new_pos.x += distance * g_Math.FastSin(angle);
+	new_pos.y += distance * g_Math.FastCos(angle);
+	new_pos.z += GetZOffset();
+
+	if (zone->HasMap()) {
+		auto new_z = zone->zonemap->FindClosestZ(new_pos, nullptr);
+		if (new_z != BEST_Z_INVALID)
+			new_pos.z = new_z;
+
+		if (zone->zonemap->FindClosestLoS(GetPosition(), new_pos, tmp_pos))
+			new_pos = tmp_pos;
+	}
+
+	new_pos.z = GetFixedZ(new_pos);
+	Teleport(new_pos);
+	if (send)
+		SendPositionUpdate();
+}
+
 int	ZoneDatabase::GetHighestGrid(uint32 zoneid) {
 
 	std::string query = StringFormat("SELECT COALESCE(MAX(id), 0) FROM grid WHERE zoneid = %i", zoneid);