Implemented basic physics for projectiles.

source/BlockTracer.h

@@ -31,12 +31,12 @@ public:
 		/** Called on each block encountered along the path, including the first block (path start)
 		When this callback returns true, the tracing is aborted.
 		*/
-		virtual bool OnNextBlock(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta) = 0;
+		virtual bool OnNextBlock(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta, char a_EntryFace) = 0;
 		
 		/** Called on each block encountered along the path, including the first block (path start), if chunk data is not loaded
 		When this callback returns true, the tracing is aborted.
 		*/
-		virtual bool OnNextBlockNoData(int a_BlockX, int a_BlockY, int a_BlockZ) { return false; }
+		virtual bool OnNextBlockNoData(int a_BlockX, int a_BlockY, int a_BlockZ, char a_EntryFace) { return false; }
 		
 		/** Called when the path goes out of world, either below (a_BlockY < 0) or above (a_BlockY >= cChunkDef::Height)
 		The coords specify the exact point at which the path exited the world.

source/Entities/ProjectileEntity.cpp

@@ -7,6 +7,57 @@
 #include "ProjectileEntity.h"
 #include "../ClientHandle.h"
 #include "Player.h"
+#include "../LineBlockTracer.h"
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cProjectileTracerCallback:
+
+class cProjectileTracerCallback :
+	public cBlockTracer::cCallbacks
+{
+public:
+	cProjectileTracerCallback(cProjectileEntity * a_Projectile) :
+		m_Projectile(a_Projectile)
+	{
+	}
+	
+protected:
+	cProjectileEntity * m_Projectile;
+	
+	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
+			m_Projectile->OnHitSolidBlock(a_BlockX, a_BlockY, a_BlockZ, a_EntryFace);
+			return true;
+		}
+		
+		// Convey some special effects from special blocks:
+		switch (a_BlockType)
+		{
+			case E_BLOCK_LAVA:
+			case E_BLOCK_STATIONARY_LAVA:
+			{
+				m_Projectile->StartBurning(30);
+				break;
+			}
+			case E_BLOCK_WATER:
+			case E_BLOCK_STATIONARY_WATER:
+			{
+				m_Projectile->StopBurning();
+				break;
+			}
+		}  // switch (a_BlockType)
+		
+		// Continue tracing
+		return false;
+	}
+} ;
 
 
 
@@ -18,7 +69,8 @@
 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_Creator(a_Creator),
+	m_IsInGround(false)
 {
 }
 
@@ -29,7 +81,8 @@ cProjectileEntity::cProjectileEntity(eKind a_Kind, cEntity * a_Creator, double a
 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_Creator(a_Creator),
+	m_IsInGround(false)
 {
 	SetSpeed(a_Speed);
 }
@@ -60,6 +113,35 @@ cProjectileEntity * cProjectileEntity::Create(eKind a_Kind, cEntity * a_Creator,
 
 
 
+void cProjectileEntity::OnHitSolidBlock(int a_BlockX, int a_BlockY, int a_BlockZ, char a_BlockFace)
+{
+	// TODO: Set proper position based on what face was hit
+	switch (a_BlockFace)
+	{
+		case BLOCK_FACE_TOP:    SetPosition(0.5 + a_BlockX, 1.0 + a_BlockY, 0.5 + a_BlockZ); break;
+		case BLOCK_FACE_BOTTOM: SetPosition(0.5 + a_BlockX,       a_BlockY, 0.5 + a_BlockZ); break;
+		case BLOCK_FACE_EAST:   SetPosition(      a_BlockX, 0.5 + a_BlockY, 0.5 + a_BlockZ); break;
+		case BLOCK_FACE_WEST:   SetPosition(1.0 + a_BlockX, 0.5 + a_BlockY, 0.5 + a_BlockZ); break;
+		case BLOCK_FACE_NORTH:  SetPosition(0.5 + a_BlockX, 0.5 + a_BlockY, 1.0 + a_BlockZ); break;
+		case BLOCK_FACE_SOUTH:  SetPosition(0.5 + a_BlockX, 0.5 + a_BlockY,       a_BlockZ); break;
+		case BLOCK_FACE_NONE:   SetPosition(0.5 + a_BlockX, 0.5 + a_BlockY, 0.5 + a_BlockZ); break;
+	}
+	SetSpeed(0, 0, 0);
+
+	// DEBUG:
+	LOGD("Projectile %d: pos {%.02f, %.02f, %.02f}, hit solid block at face %d",
+		m_UniqueID,
+		GetPosX(), GetPosY(), GetPosZ(),
+		a_BlockFace
+	);
+
+	m_IsInGround = true;
+}
+
+
+
+
+
 AString cProjectileEntity::GetMCAClassName(void) const
 {
 	switch (m_ProjectileKind)
@@ -83,6 +165,51 @@ AString cProjectileEntity::GetMCAClassName(void) const
 
 
 
+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))
+	{
+		// Nothing in the way, update the position
+		SetPosition(NextPos);
+	}
+	
+	// Add gravity effect to the vertical speed component:
+	SetSpeedY(GetSpeedY() + m_Gravity / 20);
+
+	// DEBUG:
+	LOGD("Arrow %d: pos {%.02f, %.02f, %.02f}, speed {%.02f, %.02f, %.02f}",
+		m_UniqueID,
+		GetPosX(), GetPosY(), GetPosZ(),
+		GetSpeedX(), GetSpeedY(), GetSpeedZ()
+	);
+}
+
+
+
+
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 // cArrowEntity:
 
@@ -118,22 +245,6 @@ bool cArrowEntity::CanPickup(const cPlayer & a_Player) const
 
 
 
-void cArrowEntity::Tick(float a_Dt, cChunk & a_Chunk)
-{
-	super::Tick(a_Dt, a_Chunk);
-	
-	// DEBUG:
-	LOGD("Arrow %d: pos {%.02f, %.02f, %.02f}, speed {%.02f, %.02f, %.02f}",
-		m_UniqueID,
-		GetPosX(), GetPosY(), GetPosZ(),
-		GetSpeedX(), GetSpeedY(), GetSpeedZ()
-	);
-}
-
-
-
-
-
 void cArrowEntity::SpawnOn(cClientHandle & a_Client)
 {
 	a_Client.SendSpawnObject(*this, pkArrow, 0, 0, 0);

source/Entities/ProjectileEntity.h

@@ -47,8 +47,8 @@ public:
 	
 	static cProjectileEntity * Create(eKind a_Kind, cEntity * a_Creator, double a_X, double a_Y, double a_Z, const Vector3d * a_Speed = NULL);
 	
-	/// Called by the physics blocktracer when the entity hits a solid block, the coords and the face hit is given
+	/// Called by the physics blocktracer when the entity hits a solid block, the block's coords and the face hit is given
-	virtual void OnHitSolidBlock(double a_BlockX, double a_BlockY, double a_BlockZ, char a_BlockFace) {};
+	virtual void OnHitSolidBlock(int a_BlockX, int a_BlockY, int a_BlockZ, char a_BlockFace);
 	
 	// tolua_begin
 
@@ -72,6 +72,10 @@ protected:
 	
 	/// True if the projectile has hit the ground and is stuck there
 	bool m_IsInGround;
+	
+	// cEntity overrides:
+	virtual void Tick(float a_Dt, cChunk & a_Chunk) override;
+	virtual void HandlePhysics(float a_Dt, cChunk & a_Chunk) override;
 } ;
 
 
@@ -127,7 +131,6 @@ protected:
 	double m_DamageCoeff;
 
 	// cEntity overrides:
-	virtual void Tick(float a_Dt, cChunk & a_Chunk) override;
 	virtual void SpawnOn(cClientHandle & a_Client) override;
 	
 	// tolua_begin

source/LineBlockTracer.cpp

@@ -55,6 +55,7 @@ bool cLineBlockTracer::Trace(double a_StartX, double a_StartY, double a_StartZ,
 	m_DirX = (m_StartX < m_EndX) ? 1 : -1;
 	m_DirY = (m_StartY < m_EndY) ? 1 : -1;
 	m_DirZ = (m_StartZ < m_EndZ) ? 1 : -1;
+	m_CurrentFace = BLOCK_FACE_NONE;
 	
 	// Check the start coords, adjust into the world:
 	if (m_StartY < 0)
@@ -178,9 +179,9 @@ bool cLineBlockTracer::MoveToNextBlock(void)
 	// Based on the wall hit, adjust the current coords
 	switch (Direction)
 	{
-		case dirX:    m_CurrentX += m_DirX; break;
+		case dirX:    m_CurrentX += m_DirX; m_CurrentFace = (m_DirX > 0) ? BLOCK_FACE_EAST   : BLOCK_FACE_WEST;  break;
-		case dirY:    m_CurrentY += m_DirY; break;
+		case dirY:    m_CurrentY += m_DirY; m_CurrentFace = (m_DirY > 0) ? BLOCK_FACE_BOTTOM : BLOCK_FACE_TOP;   break;
-		case dirZ:    m_CurrentZ += m_DirZ; break;
+		case dirZ:    m_CurrentZ += m_DirZ; m_CurrentFace = (m_DirZ > 0) ? BLOCK_FACE_SOUTH  : BLOCK_FACE_NORTH; break;
 		case dirNONE: return false;
 	}
 	return true;
@@ -211,7 +212,7 @@ bool cLineBlockTracer::Item(cChunk * a_Chunk)
 			int RelX = m_CurrentX - a_Chunk->GetPosX() * cChunkDef::Width;
 			int RelZ = m_CurrentZ - a_Chunk->GetPosZ() * cChunkDef::Width;
 			a_Chunk->GetBlockTypeMeta(RelX, m_CurrentY, RelZ, BlockType, BlockMeta);
-			if (m_Callbacks->OnNextBlock(m_CurrentX, m_CurrentY, m_CurrentZ, BlockType, BlockMeta))
+			if (m_Callbacks->OnNextBlock(m_CurrentX, m_CurrentY, m_CurrentZ, BlockType, BlockMeta, m_CurrentFace))
 			{
 				// The callback terminated the trace
 				return false;
@@ -219,7 +220,7 @@ bool cLineBlockTracer::Item(cChunk * a_Chunk)
 		}
 		else
 		{
-			if (m_Callbacks->OnNextBlockNoData(m_CurrentX, m_CurrentY, m_CurrentZ))
+			if (m_Callbacks->OnNextBlockNoData(m_CurrentX, m_CurrentY, m_CurrentZ, m_CurrentFace))
 			{
 				// The callback terminated the trace
 				return false;

source/LineBlockTracer.h

@@ -61,6 +61,9 @@ protected:
 	// The current block
 	int m_CurrentX, m_CurrentY, m_CurrentZ;
 	
+	// The face through which the current block has been entered
+	char m_CurrentFace;
+
 	
 	/// Adjusts the start point above the world to just at the world's top
 	void FixStartAboveWorld(void);

source/ManualBindings.cpp

@@ -1649,7 +1649,7 @@ public:
 	{
 	}
 	
-	virtual bool OnNextBlock(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta) override
+	virtual bool OnNextBlock(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta, char a_EntryFace) override
 	{
 		if (!m_LuaState.PushFunctionFromRefTable(m_TableRef, "OnNextBlock"))
 		{
@@ -1661,6 +1661,7 @@ public:
 		m_LuaState.Push(a_BlockZ);
 		m_LuaState.Push(a_BlockType);
 		m_LuaState.Push(a_BlockMeta);
+		m_LuaState.Push(a_EntryFace);
 		if (!m_LuaState.CallFunction(1))
 		{
 			return false;
@@ -1674,7 +1675,7 @@ public:
 		return res;
 	}
 	
-	virtual bool OnNextBlockNoData(int a_BlockX, int a_BlockY, int a_BlockZ) override
+	virtual bool OnNextBlockNoData(int a_BlockX, int a_BlockY, int a_BlockZ, char a_EntryFace) override
 	{
 		if (!m_LuaState.PushFunctionFromRefTable(m_TableRef, "OnNextBlockNoData"))
 		{
@@ -1684,6 +1685,7 @@ public:
 		m_LuaState.Push(a_BlockX);
 		m_LuaState.Push(a_BlockY);
 		m_LuaState.Push(a_BlockZ);
+		m_LuaState.Push(a_EntryFace);
 		if (!m_LuaState.CallFunction(1))
 		{
 			return false;

source/Vector3d.h

@@ -30,12 +30,13 @@ public:			// tolua_export
 	void operator -= ( Vector3d* a_V ) { x -= a_V->x; y -= a_V->y; z -= a_V->z; }
 	void operator *= ( double a_f ) { x *= a_f; y *= a_f; z *= a_f; }
 
-	Vector3d operator + ( const Vector3d& v2 ) const { return Vector3d( x + v2.x, y + v2.y, z + v2.z ); }									// tolua_export
+	Vector3d operator + (const Vector3d & v2) const { return Vector3d(x + v2.x, y + v2.y, z + v2.z ); }     // tolua_export
-	Vector3d operator + ( const Vector3d* v2 ) const { return Vector3d( x + v2->x, y + v2->y, z + v2->z ); }								// tolua_export
+	Vector3d operator + (const Vector3d * v2) const { return Vector3d(x + v2->x, y + v2->y, z + v2->z ); }  // tolua_export
-	Vector3d operator - ( const Vector3d& v2 ) const { return Vector3d( x - v2.x, y - v2.y, z - v2.z ); }									// tolua_export
+	Vector3d operator - (const Vector3d & v2) const { return Vector3d(x - v2.x, y - v2.y, z - v2.z ); }     // tolua_export
-	Vector3d operator - ( const Vector3d* v2 ) const { return Vector3d( x - v2->x, y - v2->y, z - v2->z ); }								// tolua_export
+	Vector3d operator - (const Vector3d * v2) const { return Vector3d(x - v2->x, y - v2->y, z - v2->z ); }  // tolua_export
-	Vector3d operator * ( const double f ) const { return Vector3d( x * f, y * f, z * f ); }												// tolua_export
+	Vector3d operator * (const double f)      const { return Vector3d(x * f, y * f, z * f ); }              // tolua_export
-	Vector3d operator * ( const Vector3d& v2 ) const { return Vector3d( x * v2.x, y * v2.y, z * v2.z ); }									// tolua_export
+	Vector3d operator * (const Vector3d & v2) const { return Vector3d(x * v2.x, y * v2.y, z * v2.z ); }     // tolua_export
+	Vector3d operator / (const double f)      const { return Vector3d(x / f, y / f, z / f ); }              // tolua_export
 
 	double x, y, z;	// tolua_export