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cuberite-2a/source/Entities/ProjectileEntity.cpp

621 lines
16 KiB
C++

// ProjectileEntity.cpp
// Implements the cProjectileEntity class representing the common base class for projectiles, as well as individual projectile types
#include "Globals.h"
#include "ProjectileEntity.h"
#include "../ClientHandle.h"
#include "Player.h"
#include "../LineBlockTracer.h"
#include "../BoundingBox.h"
#include "../ChunkMap.h"
#include "../Chunk.h"
/// Converts an angle in radians into a byte representation used by the network protocol
#define ANGLE_TO_PROTO(X) (Byte)(X * 255 / 360)
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cProjectileTracerCallback:
class cProjectileTracerCallback :
public cBlockTracer::cCallbacks
{
public:
cProjectileTracerCallback(cProjectileEntity * a_Projectile) :
m_Projectile(a_Projectile),
m_SlowdownCoeff(0.99) // Default slowdown when not in water
{
}
double GetSlowdownCoeff(void) const { return m_SlowdownCoeff; }
protected:
cProjectileEntity * m_Projectile;
double m_SlowdownCoeff;
// cCallbacks overrides:
virtual bool OnNextBlock(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta, char a_EntryFace) override
{
if (g_BlockIsSolid[a_BlockType])
{
// The projectile hit a solid block
// Calculate the exact hit coords:
cBoundingBox bb(a_BlockX, a_BlockX + 1, a_BlockY, a_BlockY + 1, a_BlockZ, a_BlockZ + 1);
Vector3d Line1 = m_Projectile->GetPosition();
Vector3d Line2 = Line1 + m_Projectile->GetSpeed();
double LineCoeff = 0;
char Face;
if (bb.CalcLineIntersection(Line1, Line2, LineCoeff, Face))
{
Vector3d Intersection = Line1 + m_Projectile->GetSpeed() * LineCoeff;
m_Projectile->OnHitSolidBlock(Intersection, Face);
return true;
}
else
{
LOGD("WEIRD! block tracer reports a hit, but BBox tracer doesn't. Ignoring the hit.");
}
}
// Convey some special effects from special blocks:
switch (a_BlockType)
{
case E_BLOCK_LAVA:
case E_BLOCK_STATIONARY_LAVA:
{
m_Projectile->StartBurning(30);
m_SlowdownCoeff = std::min(m_SlowdownCoeff, 0.9); // Slow down to 0.9* the speed each tick when moving through lava
break;
}
case E_BLOCK_WATER:
case E_BLOCK_STATIONARY_WATER:
{
m_Projectile->StopBurning();
m_SlowdownCoeff = std::min(m_SlowdownCoeff, 0.8); // Slow down to 0.8* the speed each tick when moving through water
break;
}
} // switch (a_BlockType)
// Continue tracing
return false;
}
} ;
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cProjectileEntityCollisionCallback:
class cProjectileEntityCollisionCallback :
public cEntityCallback
{
public:
cProjectileEntityCollisionCallback(cProjectileEntity * a_Projectile, const Vector3d & a_Pos, const Vector3d & a_NextPos) :
m_Projectile(a_Projectile),
m_Pos(a_Pos),
m_NextPos(a_NextPos),
m_MinCoeff(1),
m_HitEntity(NULL)
{
}
virtual bool Item(cEntity * a_Entity) override
{
if (
(a_Entity == m_Projectile) || // Do not check collisions with self
(a_Entity == m_Projectile->GetCreator()) // Do not check whoever shot the projectile
)
{
// TODO: Don't check creator only for the first 5 ticks
// so that arrows stuck in ground and dug up can hurt the player
return false;
}
cBoundingBox EntBox(a_Entity->GetPosition(), a_Entity->GetWidth() / 2, a_Entity->GetHeight());
// Instead of colliding the bounding box with another bounding box in motion, we collide an enlarged bounding box with a hairline.
// The results should be good enough for our purposes
double LineCoeff;
char Face;
EntBox.Expand(m_Projectile->GetWidth() / 2, m_Projectile->GetHeight() / 2, m_Projectile->GetWidth() / 2);
if (!EntBox.CalcLineIntersection(m_Pos, m_NextPos, LineCoeff, Face))
{
// No intersection whatsoever
return false;
}
// TODO: Some entities don't interact with the projectiles (pickups, falling blocks)
// TODO: Allow plugins to interfere about which entities can be hit
if (LineCoeff < m_MinCoeff)
{
// The entity is closer than anything we've stored so far, replace it as the potential victim
m_MinCoeff = LineCoeff;
m_HitEntity = a_Entity;
}
// Don't break the enumeration, we want all the entities
return false;
}
/// Returns the nearest entity that was hit, after the enumeration has been completed
cEntity * GetHitEntity(void) const { return m_HitEntity; }
/// Returns the line coeff where the hit was encountered, after the enumeration has been completed
double GetMinCoeff(void) const { return m_MinCoeff; }
/// Returns true if the callback has encountered a true hit
bool HasHit(void) const { return (m_MinCoeff < 1); }
protected:
cProjectileEntity * m_Projectile;
const Vector3d & m_Pos;
const Vector3d & m_NextPos;
double m_MinCoeff; // The coefficient of the nearest hit on the Pos line
// Although it's bad(tm) to store entity ptrs from a callback, we can afford it here, because the entire callback
// is processed inside the tick thread, so the entities won't be removed in between the calls and the final processing
cEntity * m_HitEntity; // The nearest hit entity
} ;
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cProjectileEntity:
cProjectileEntity::cProjectileEntity(eKind a_Kind, cEntity * a_Creator, double a_X, double a_Y, double a_Z, double a_Width, double a_Height) :
super(etProjectile, a_X, a_Y, a_Z, a_Width, a_Height),
m_ProjectileKind(a_Kind),
m_Creator(a_Creator),
m_IsInGround(false)
{
}
cProjectileEntity::cProjectileEntity(eKind a_Kind, cEntity * a_Creator, const Vector3d & a_Pos, const Vector3d & a_Speed, double a_Width, double a_Height) :
super(etProjectile, a_Pos.x, a_Pos.y, a_Pos.z, a_Width, a_Height),
m_ProjectileKind(a_Kind),
m_Creator(a_Creator),
m_IsInGround(false)
{
SetSpeed(a_Speed);
SetRotationFromSpeed();
SetPitchFromSpeed();
}
cProjectileEntity * cProjectileEntity::Create(eKind a_Kind, cEntity * a_Creator, double a_X, double a_Y, double a_Z, const Vector3d * a_Speed)
{
Vector3d Speed;
if (a_Speed != NULL)
{
Speed = *a_Speed;
}
switch (a_Kind)
{
case pkArrow: return new cArrowEntity (a_Creator, a_X, a_Y, a_Z, Speed);
case pkEgg: return new cThrownEggEntity (a_Creator, a_X, a_Y, a_Z, Speed);
case pkEnderPearl: return new cThrownEnderPearlEntity(a_Creator, a_X, a_Y, a_Z, Speed);
case pkSnowball: return new cThrownSnowballEntity (a_Creator, a_X, a_Y, a_Z, Speed);
case pkGhastFireball: return new cGhastFireballEntity (a_Creator, a_X, a_Y, a_Z, Speed);
case pkFireCharge: return new cFireChargeEntity (a_Creator, a_X, a_Y, a_Z, Speed);
// TODO: the rest
}
LOGWARNING("%s: Unknown projectile kind: %d", __FUNCTION__, a_Kind);
return NULL;
}
void cProjectileEntity::OnHitSolidBlock(const Vector3d & a_HitPos, char a_HitFace)
{
// Set the position based on what face was hit:
SetPosition(a_HitPos);
SetSpeed(0, 0, 0);
// DEBUG:
LOGD("Projectile %d: pos {%.02f, %.02f, %.02f}, hit solid block at face %d",
m_UniqueID,
a_HitPos.x, a_HitPos.y, a_HitPos.z,
a_HitFace
);
m_IsInGround = true;
}
AString cProjectileEntity::GetMCAClassName(void) const
{
switch (m_ProjectileKind)
{
case pkArrow: return "Arrow";
case pkSnowball: return "Snowball";
case pkEgg: return "Egg";
case pkGhastFireball: return "Fireball";
case pkFireCharge: return "SmallFireball";
case pkEnderPearl: return "ThrownEnderPearl";
case pkExpBottle: return "ThrownExpBottle";
case pkSplashPotion: return "ThrownPotion";
case pkWitherSkull: return "WitherSkull";
case pkFishingFloat: return ""; // Unknown, perhaps MC doesn't save this?
}
ASSERT(!"Unhandled projectile entity kind!");
return "";
}
void cProjectileEntity::Tick(float a_Dt, cChunk & a_Chunk)
{
super::Tick(a_Dt, a_Chunk);
BroadcastMovementUpdate();
}
void cProjectileEntity::HandlePhysics(float a_Dt, cChunk & a_Chunk)
{
if (m_IsInGround)
{
// Already-grounded projectiles don't move at all
return;
}
Vector3d PerTickSpeed = GetSpeed() / 20;
Vector3d Pos = GetPosition();
// Trace the tick's worth of movement as a line:
Vector3d NextPos = Pos + PerTickSpeed;
cProjectileTracerCallback TracerCallback(this);
if (!cLineBlockTracer::Trace(*m_World, TracerCallback, Pos, NextPos))
{
// Something has been hit, abort all other processing
return;
}
// The tracer also checks the blocks for slowdown blocks - water and lava - and stores it for later in its SlowdownCoeff
// Test for entity collisions:
cProjectileEntityCollisionCallback EntityCollisionCallback(this, Pos, NextPos);
a_Chunk.ForEachEntity(EntityCollisionCallback);
if (EntityCollisionCallback.HasHit())
{
// An entity was hit:
Vector3d HitPos = Pos + (NextPos - Pos) * EntityCollisionCallback.GetMinCoeff();
// DEBUG:
LOGD("Projectile %d has hit an entity %d (%s) at {%.02f, %.02f, %.02f} (coeff %.03f)",
m_UniqueID,
EntityCollisionCallback.GetHitEntity()->GetUniqueID(),
EntityCollisionCallback.GetHitEntity()->GetClass(),
HitPos.x, HitPos.y, HitPos.z,
EntityCollisionCallback.GetMinCoeff()
);
OnHitEntity(*(EntityCollisionCallback.GetHitEntity()), HitPos);
}
// TODO: Test the entities in the neighboring chunks, too
// Update the position:
SetPosition(NextPos);
// Add slowdown and gravity effect to the speed:
Vector3d NewSpeed(GetSpeed());
NewSpeed.y += m_Gravity / 20;
NewSpeed *= TracerCallback.GetSlowdownCoeff();
SetSpeed(NewSpeed);
SetRotationFromSpeed();
SetPitchFromSpeed();
// DEBUG:
LOGD("Projectile %d: pos {%.02f, %.02f, %.02f}, speed {%.02f, %.02f, %.02f}, rot {%.02f, %.02f}",
m_UniqueID,
GetPosX(), GetPosY(), GetPosZ(),
GetSpeedX(), GetSpeedY(), GetSpeedZ(),
GetRotation(), GetPitch()
);
}
void cProjectileEntity::SpawnOn(cClientHandle & a_Client)
{
// Default spawning - use the projectile kind to spawn an object:
a_Client.SendSpawnObject(*this, m_ProjectileKind, 12, ANGLE_TO_PROTO(GetRotation()), ANGLE_TO_PROTO(GetPitch()));
a_Client.SendEntityMetadata(*this);
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cArrowEntity:
cArrowEntity::cArrowEntity(cEntity * a_Creator, double a_X, double a_Y, double a_Z, const Vector3d & a_Speed) :
super(pkArrow, a_Creator, a_X, a_Y, a_Z, 0.5, 0.5),
m_PickupState(psNoPickup),
m_DamageCoeff(2),
m_IsCritical(false)
{
SetSpeed(a_Speed);
SetMass(0.1);
SetRotationFromSpeed();
SetPitchFromSpeed();
LOGD("Created arrow %d with speed {%.02f, %.02f, %.02f} and rot {%.02f, %.02f}",
m_UniqueID, GetSpeedX(), GetSpeedY(), GetSpeedZ(),
GetRotation(), GetPitch()
);
}
cArrowEntity::cArrowEntity(cPlayer & a_Player, double a_Force) :
super(pkArrow, &a_Player, a_Player.GetThrowStartPos(), a_Player.GetThrowSpeed(a_Force * 1.5 * 20), 0.5, 0.5),
m_PickupState(psInSurvivalOrCreative),
m_DamageCoeff(2),
m_IsCritical((a_Force >= 1))
{
}
bool cArrowEntity::CanPickup(const cPlayer & a_Player) const
{
switch (m_PickupState)
{
case psNoPickup: return false;
case psInSurvivalOrCreative: return (a_Player.IsGameModeSurvival() || a_Player.IsGameModeCreative());
case psInCreative: return a_Player.IsGameModeCreative();
}
ASSERT(!"Unhandled pickup state");
return false;
}
void cArrowEntity::OnHitSolidBlock(const Vector3d & a_HitPos, char a_HitFace)
{
super::OnHitSolidBlock(a_HitPos, a_HitFace);
// Broadcast the position and speed packets before teleporting:
BroadcastMovementUpdate();
// Teleport the entity to the exact hit coords:
m_World->BroadcastTeleportEntity(*this);
}
void cArrowEntity::OnHitEntity(cEntity & a_EntityHit, const Vector3d & a_HitPos)
{
if (!a_EntityHit.IsMob() && !a_EntityHit.IsMinecart() && !a_EntityHit.IsPlayer())
{
// Not an entity that interacts with an arrow
return;
}
int Damage = (int)(GetSpeed().Length() / 20 * m_DamageCoeff + 0.5);
if (m_IsCritical)
{
Damage += m_World->GetTickRandomNumber(Damage / 2 + 2);
}
a_EntityHit.TakeDamage(dtRangedAttack, this, Damage, 1);
Destroy();
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cThrownEggEntity:
cThrownEggEntity::cThrownEggEntity(cEntity * a_Creator, double a_X, double a_Y, double a_Z, const Vector3d & a_Speed) :
super(pkEgg, a_Creator, a_X, a_Y, a_Z, 0.25, 0.25)
{
SetSpeed(a_Speed);
}
void cThrownEggEntity::OnHitSolidBlock(const Vector3d & a_HitPos, char a_HitFace)
{
// TODO: Random-spawn a chicken or four
Destroy();
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cThrownEnderPearlEntity :
cThrownEnderPearlEntity::cThrownEnderPearlEntity(cEntity * a_Creator, double a_X, double a_Y, double a_Z, const Vector3d & a_Speed) :
super(pkEnderPearl, a_Creator, a_X, a_Y, a_Z, 0.25, 0.25)
{
SetSpeed(a_Speed);
}
void cThrownEnderPearlEntity::OnHitSolidBlock(const Vector3d & a_HitPos, char a_HitFace)
{
// Teleport the creator here, make them take 5 damage:
if (m_Creator != NULL)
{
// TODO: The coords might need some tweaking based on the block face
m_Creator->TeleportToCoords(a_HitPos.x + 0.5, a_HitPos.y + 1.7, a_HitPos.z + 0.5);
m_Creator->TakeDamage(dtEnderPearl, this, 5, 0);
}
Destroy();
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cThrownSnowballEntity :
cThrownSnowballEntity::cThrownSnowballEntity(cEntity * a_Creator, double a_X, double a_Y, double a_Z, const Vector3d & a_Speed) :
super(pkSnowball, a_Creator, a_X, a_Y, a_Z, 0.25, 0.25)
{
SetSpeed(a_Speed);
}
void cThrownSnowballEntity::OnHitSolidBlock(const Vector3d & a_HitPos, char a_HitFace)
{
// TODO: Apply damage to certain mobs (blaze etc.) and anger all mobs
Destroy();
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cGhastFireballEntity :
cGhastFireballEntity::cGhastFireballEntity(cEntity * a_Creator, double a_X, double a_Y, double a_Z, const Vector3d & a_Speed) :
super(pkGhastFireball, a_Creator, a_X, a_Y, a_Z, 1, 1)
{
SetSpeed(a_Speed);
SetGravity(0);
}
void cGhastFireballEntity::Explode(int a_BlockX, int a_BlockY, int a_BlockZ)
{
m_World->DoExplosionAt(1, a_BlockX, a_BlockY, a_BlockZ, true, esGhastFireball, this);
}
void cGhastFireballEntity::OnHitSolidBlock(const Vector3d & a_HitPos, char a_HitFace)
{
Destroy();
Explode((int)floor(a_HitPos.x), (int)floor(a_HitPos.y), (int)floor(a_HitPos.z));
}
void cGhastFireballEntity::OnHitEntity(cEntity & a_EntityHit, const Vector3d & a_HitPos)
{
Destroy();
Explode((int)floor(a_HitPos.x), (int)floor(a_HitPos.y), (int)floor(a_HitPos.z));
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cFireChargeEntity :
cFireChargeEntity::cFireChargeEntity(cEntity * a_Creator, double a_X, double a_Y, double a_Z, const Vector3d & a_Speed) :
super(pkFireCharge, a_Creator, a_X, a_Y, a_Z, 0.3125, 0.3125)
{
SetSpeed(a_Speed);
SetGravity(0);
}
void cFireChargeEntity::Explode(int a_BlockX, int a_BlockY, int a_BlockZ)
{
if (m_World->GetBlock(a_BlockX, a_BlockY, a_BlockZ) == E_BLOCK_AIR)
{
m_World->SetBlock(a_BlockX, a_BlockY, a_BlockZ, E_BLOCK_FIRE, 1);
}
}
void cFireChargeEntity::OnHitSolidBlock(const Vector3d & a_HitPos, char a_HitFace)
{
Destroy();
Explode((int)floor(a_HitPos.x), (int)floor(a_HitPos.y), (int)floor(a_HitPos.z));
}
void cFireChargeEntity::OnHitEntity(cEntity & a_EntityHit, const Vector3d & a_HitPos)
{
Destroy();
Explode((int)floor(a_HitPos.x), (int)floor(a_HitPos.y), (int)floor(a_HitPos.z));
// TODO: Some entities are immune to hits
a_EntityHit.StartBurning(5 * 20); // 5 seconds of burning
}