/* (c) Magnus Auvinen. See licence.txt in the root of the distribution for more information. */
/* If you are missing that file, acquire a complete release at teeworlds.com.                */
#include <base/system.h>
#include <base/math.h>
#include <base/vmath.h>

#include <math.h>
#include <engine/map.h>
#include <engine/kernel.h>

#include <game/mapitems.h>
#include <game/layers.h>
#include <game/collision.h>

#include <engine/shared/config.h>

CCollision::CCollision()
{
	m_pTiles = 0;
	m_Width = 0;
	m_Height = 0;
	m_pLayers = 0;

	m_pTele = 0;
	m_pSpeedup = 0;
	m_pFront = 0;
	m_pSwitch = 0;
	m_pDoor = 0;
	m_pSwitchers = 0;
}

void CCollision::Init(class CLayers *pLayers)
{
	if(m_pLayers) m_pLayers->Dest();
	Dest();
	m_NumSwitchers = 0;
	m_pLayers = pLayers;
	m_Width = m_pLayers->GameLayer()->m_Width;
	m_Height = m_pLayers->GameLayer()->m_Height;
	m_pTiles = static_cast<CTile *>(m_pLayers->Map()->GetData(m_pLayers->GameLayer()->m_Data));

	if(m_pLayers->TeleLayer())
		m_pTele = static_cast<CTeleTile *>(m_pLayers->Map()->GetData(m_pLayers->TeleLayer()->m_Tele));

	if(m_pLayers->SpeedupLayer())
		m_pSpeedup = static_cast<CSpeedupTile *>(m_pLayers->Map()->GetData(m_pLayers->SpeedupLayer()->m_Speedup));

	if(m_pLayers->SwitchLayer())
	{
		m_pSwitch = static_cast<CSwitchTile *>(m_pLayers->Map()->GetData(m_pLayers->SwitchLayer()->m_Switch));
		m_pDoor = new CDoorTile[m_Width*m_Height];
		mem_zero(m_pDoor, m_Width * m_Height * sizeof(CDoorTile));
	}
	else
	{
		m_pDoor = 0;
		m_pSwitchers = 0;
	}

	if(m_pLayers->FrontLayer())
		m_pFront = static_cast<CTile *>(m_pLayers->Map()->GetData(m_pLayers->FrontLayer()->m_Front));

	for(int i = 0; i < m_Width*m_Height; i++)
	{
		int Index;
		if(m_pSwitch)
		{
			if(m_pSwitch[i].m_Number > m_NumSwitchers)
				m_NumSwitchers = m_pSwitch[i].m_Number;

			if(m_pSwitch[i].m_Number)
				m_pDoor[i].m_Number = m_pSwitch[i].m_Number;
			else
				m_pDoor[i].m_Number = 0;

			Index = m_pSwitch[i].m_Type;

			if(Index <= TILE_NPH)
			{
				if(Index >= TILE_FREEZE && Index <= TILE_SWITCHCLOSE)
					m_pSwitch[i].m_Type = Index;
				else
					m_pSwitch[i].m_Type = 0;
			}
		}
		if(m_pFront)
		{
			Index = m_pFront[i].m_Index;

			if(Index <= TILE_NPH)
			{
				switch(Index)
				{
				case TILE_DEATH:
					m_pFront[i].m_Index = COLFLAG_DEATH;
					break;
				case TILE_SOLID:
					m_pFront[i].m_Index = 0;
					break;
				case TILE_NOHOOK:
					m_pFront[i].m_Index = 0;
					break;
				case TILE_NOLASER:
					m_pFront[i].m_Index = COLFLAG_NOLASER;
					break;
				default:
					m_pFront[i].m_Index = 0;
				}

				// DDRace tiles
				if(Index == TILE_THROUGH || (Index >= TILE_FREEZE && Index <= TILE_UNFREEZE) || (Index >= TILE_SWITCHOPEN && Index <= TILE_TELECHECKIN) || (Index >= TILE_BEGIN && Index <= TILE_STOPA) || Index == TILE_CP || Index == TILE_CP_F || (Index >= TILE_OLDLASER && Index <= TILE_NPH) || (Index >= TILE_EHOOK_START && Index <= TILE_EHOOK_END) || (Index >= TILE_DFREEZE && Index <= TILE_DUNFREEZE))
					m_pFront[i].m_Index = Index;
			}
		}
		Index = m_pTiles[i].m_Index;
		if(Index <= TILE_NPH)
		{
			switch(Index)
			{
			case TILE_DEATH:
				m_pTiles[i].m_Index = COLFLAG_DEATH;
				break;
			case TILE_SOLID:
				m_pTiles[i].m_Index = COLFLAG_SOLID;
				break;
			case TILE_NOHOOK:
				m_pTiles[i].m_Index = COLFLAG_SOLID|COLFLAG_NOHOOK;
				break;
			case TILE_NOLASER:
				m_pTiles[i].m_Index = COLFLAG_NOLASER;
				break;
			default:
				m_pTiles[i].m_Index = 0;
			}

			// DDRace tiles
			if(Index == TILE_THROUGH || (Index >= TILE_FREEZE && Index <= TILE_UNFREEZE) || (Index >= TILE_SWITCHOPEN && Index <= TILE_TELECHECKIN) || (Index >= TILE_BEGIN && Index <= TILE_STOPA) || Index == TILE_CP || Index == TILE_CP_F || (Index >= TILE_OLDLASER && Index <= TILE_NPH) || (Index >= TILE_EHOOK_START && Index <= TILE_EHOOK_END) || (Index >= TILE_DFREEZE && Index <= TILE_DUNFREEZE))
				m_pTiles[i].m_Index = Index;
		}
	}
	if(m_NumSwitchers)
	{
		m_pSwitchers = new SSwitchers[m_NumSwitchers+1];

		for (int i = 0; i < m_NumSwitchers+1; ++i)
		{
			for (int j = 0; j < 16; ++j)
			{
				m_pSwitchers[i].m_Status[j] = true;
				m_pSwitchers[i].m_EndTick[j] = 0;
				m_pSwitchers[i].m_Type[j] = 0;
			}
		}
	}
}

int CCollision::GetTile(int x, int y)
{
	int Nx = clamp(x/32, 0, m_Width-1);
	int Ny = clamp(y/32, 0, m_Height-1);
	if(!m_pTiles || Ny < 0 || Nx < 0)
		return 0;

	if(m_pTiles[Ny*m_Width+Nx].m_Index == COLFLAG_SOLID
		|| m_pTiles[Ny*m_Width+Nx].m_Index == (COLFLAG_SOLID|COLFLAG_NOHOOK)
		|| m_pTiles[Ny*m_Width+Nx].m_Index == COLFLAG_DEATH
		|| m_pTiles[Ny*m_Width+Nx].m_Index == COLFLAG_NOLASER)
		return m_pTiles[Ny*m_Width+Nx].m_Index;
	return 0;
}
/*
bool CCollision::IsTileSolid(int x, int y)
{
	return GetTile(x, y)&COLFLAG_SOLID;
}
*/
// TODO: rewrite this smarter!
int CCollision::IntersectLine(vec2 Pos0, vec2 Pos1, vec2 *pOutCollision, vec2 *pOutBeforeCollision, bool AllowThrough)
{
	float Distance = distance(Pos0, Pos1);
	int End(Distance+1);
	vec2 Last = Pos0;
	int ix = 0, iy = 0; // Temporary position for checking collision
	int dx = 0, dy = 0; // Offset for checking the "through" tile
	if (AllowThrough)
		{
			ThroughOffset(Pos0, Pos1, &dx, &dy);
		}
	for(int i = 0; i < End; i++)
	{
		float a = i/Distance;
		vec2 Pos = mix(Pos0, Pos1, a);
		ix = round(Pos.x);
		iy = round(Pos.y);
		if(CheckPoint(ix, iy) && !(AllowThrough && IsThrough(ix + dx, iy + dy)))
		{
			if(pOutCollision)
				*pOutCollision = Pos;
			if(pOutBeforeCollision)
				*pOutBeforeCollision = Last;
			return GetCollisionAt(ix, iy);
		}
		Last = Pos;
	}
	if(pOutCollision)
		*pOutCollision = Pos1;
	if(pOutBeforeCollision)
		*pOutBeforeCollision = Pos1;
	return 0;
}

// TODO: OPT: rewrite this smarter!
void CCollision::MovePoint(vec2 *pInoutPos, vec2 *pInoutVel, float Elasticity, int *pBounces)
{
	if(pBounces)
		*pBounces = 0;

	vec2 Pos = *pInoutPos;
	vec2 Vel = *pInoutVel;
	if(CheckPoint(Pos + Vel))
	{
		int Affected = 0;
		if(CheckPoint(Pos.x + Vel.x, Pos.y))
		{
			pInoutVel->x *= -Elasticity;
			if(pBounces)
				(*pBounces)++;
			Affected++;
		}

		if(CheckPoint(Pos.x, Pos.y + Vel.y))
		{
			pInoutVel->y *= -Elasticity;
			if(pBounces)
				(*pBounces)++;
			Affected++;
		}

		if(Affected == 0)
		{
			pInoutVel->x *= -Elasticity;
			pInoutVel->y *= -Elasticity;
		}
	}
	else
	{
		*pInoutPos = Pos + Vel;
	}
}

bool CCollision::TestBox(vec2 Pos, vec2 Size)
{
	Size *= 0.5f;
	if(CheckPoint(Pos.x-Size.x, Pos.y-Size.y))
		return true;
	if(CheckPoint(Pos.x+Size.x, Pos.y-Size.y))
		return true;
	if(CheckPoint(Pos.x-Size.x, Pos.y+Size.y))
		return true;
	if(CheckPoint(Pos.x+Size.x, Pos.y+Size.y))
		return true;
	return false;
}

void CCollision::MoveBox(vec2 *pInoutPos, vec2 *pInoutVel, vec2 Size, float Elasticity)
{
	// do the move
	vec2 Pos = *pInoutPos;
	vec2 Vel = *pInoutVel;

	float Distance = length(Vel);
	int Max = (int)Distance;

	if(Distance > 0.00001f)
	{
		//vec2 old_pos = pos;
		float Fraction = 1.0f/(float)(Max+1);
		for(int i = 0; i <= Max; i++)
		{
			//float amount = i/(float)max;
			//if(max == 0)
				//amount = 0;

			vec2 NewPos = Pos + Vel*Fraction; // TODO: this row is not nice

			if(TestBox(vec2(NewPos.x, NewPos.y), Size))
			{
				int Hits = 0;

				if(TestBox(vec2(Pos.x, NewPos.y), Size))
				{
					NewPos.y = Pos.y;
					Vel.y *= -Elasticity;
					Hits++;
				}

				if(TestBox(vec2(NewPos.x, Pos.y), Size))
				{
					NewPos.x = Pos.x;
					Vel.x *= -Elasticity;
					Hits++;
				}

				// neither of the tests got a collision.
				// this is a real _corner case_!
				if(Hits == 0)
				{
					NewPos.y = Pos.y;
					Vel.y *= -Elasticity;
					NewPos.x = Pos.x;
					Vel.x *= -Elasticity;
				}
			}

			Pos = NewPos;
		}
	}

	*pInoutPos = Pos;
	*pInoutVel = Vel;
}

// DDRace

void CCollision::Dest()
{
	if(m_pDoor)
		delete[] m_pDoor;
	if(m_pSwitchers)
		delete[] m_pSwitchers;
	m_pTiles = 0;
	m_Width = 0;
	m_Height = 0;
	m_pLayers = 0;
	m_pTele = 0;
	m_pSpeedup = 0;
	m_pFront = 0;
	m_pSwitch = 0;
	m_pDoor = 0;
	m_pSwitchers = 0;
}

int CCollision::IsSolid(int x, int y)
{
	return (GetTile(x,y)&COLFLAG_SOLID);
}

int CCollision::IsThrough(int x, int y)
{
	int Nx = clamp(x/32, 0, m_Width-1);
	int Ny = clamp(y/32, 0, m_Height-1);
	int Index = m_pTiles[Ny*m_Width+Nx].m_Index;
	int Findex = 0;
	if (m_pFront)
		Findex = m_pFront[Ny*m_Width+Nx].m_Index;
	if(!g_Config.m_ClPredictOldHookthrough)
	{
		if (Index == TILE_THROUGH)
			return Index;
		if (Findex == TILE_THROUGH)
			return Findex;
	}
	else
	{
		if (Index == OLD_THROUGH1)
			return Index;
		if (Findex == OLD_THROUGH1)
			return Findex;
		if (Index == OLD_THROUGH2)
			return Index;
		if (Findex == OLD_THROUGH2)
			return Findex;
	}
	return 0;
}

int CCollision::IsNoLaser(int x, int y)
{
   return (CCollision::GetTile(x,y) & COLFLAG_NOLASER);
}

int CCollision::IsFNoLaser(int x, int y)
{
   return (CCollision::GetFTile(x,y) & COLFLAG_NOLASER);
}

int CCollision::IsTeleport(int Index)
{
	if(Index < 0 || !m_pTele)
		return 0;

	if(m_pTele[Index].m_Type == TILE_TELEIN)
		return m_pTele[Index].m_Number;

	return 0;
}

int CCollision::IsEvilTeleport(int Index)
{
	if(Index < 0)
		return 0;
	if(!m_pTele)
		return 0;

	if(m_pTele[Index].m_Type == TILE_TELEINEVIL)
		return m_pTele[Index].m_Number;

	return 0;
}

int CCollision::IsCheckTeleport(int Index)
{
	if(Index < 0)
		return 0;
	if(!m_pTele)
		return 0;

	if(m_pTele[Index].m_Type == TILE_TELECHECKIN)
		return m_pTele[Index].m_Number;

	return 0;
}

int CCollision::IsTCheckpoint(int Index)
{
	if(Index < 0)
		return 0;

	if(!m_pTele)
		return 0;

	if(m_pTele[Index].m_Type == TILE_TELECHECK)
		return m_pTele[Index].m_Number;

	return 0;
}

int CCollision::IsSpeedup(int Index)
{
	if(Index < 0 || !m_pSpeedup)
		return 0;

	if(m_pSpeedup[Index].m_Force > 0)
		return Index;

	return 0;
}

void CCollision::GetSpeedup(int Index, vec2 *Dir, int *Force, int *MaxSpeed)
{
	if(Index < 0 || !m_pSpeedup)
		return;
	vec2 Direction = vec2(1, 0);
	float Angle = m_pSpeedup[Index].m_Angle * (pi / 180.0f);
	*Force = m_pSpeedup[Index].m_Force;
	*Dir = vec2(cos(Angle), sin(Angle));
	if(MaxSpeed)
		*MaxSpeed = m_pSpeedup[Index].m_MaxSpeed;
}

int CCollision::IsSwitch(int Index)
{
	//dbg_msg("IsSwitch","Index %d, pSwitch %d, m_Type %d, m_Number %d", Index, m_pSwitch, (m_pSwitch)?m_pSwitch[Index].m_Type:0, (m_pSwitch)?m_pSwitch[Index].m_Number:0);
	if(Index < 0 || !m_pSwitch)
		return 0;

	if(m_pSwitch[Index].m_Type > 0)
		return m_pSwitch[Index].m_Type;

	return 0;
}

int CCollision::GetSwitchNumber(int Index)
{
	//dbg_msg("GetSwitchNumber","Index %d, pSwitch %d, m_Type %d, m_Number %d", Index, m_pSwitch, (m_pSwitch)?m_pSwitch[Index].m_Type:0, (m_pSwitch)?m_pSwitch[Index].m_Number:0);
	if(Index < 0 || !m_pSwitch)
		return 0;

	if(m_pSwitch[Index].m_Type > 0 && m_pSwitch[Index].m_Number > 0)
		return m_pSwitch[Index].m_Number;

	return 0;
}

int CCollision::GetSwitchDelay(int Index)
{
	//dbg_msg("GetSwitchNumber","Index %d, pSwitch %d, m_Type %d, m_Number %d", Index, m_pSwitch, (m_pSwitch)?m_pSwitch[Index].m_Type:0, (m_pSwitch)?m_pSwitch[Index].m_Number:0);
	if(Index < 0 || !m_pSwitch)
		return 0;

	if(m_pSwitch[Index].m_Type > 0)
		return m_pSwitch[Index].m_Delay;

	return 0;
}

int CCollision::IsMover(int x, int y, int* Flags)
{
	int Nx = clamp(x/32, 0, m_Width-1);
	int Ny = clamp(y/32, 0, m_Height-1);
	int Index = m_pTiles[Ny*m_Width+Nx].m_Index;
	*Flags = m_pTiles[Ny*m_Width+Nx].m_Flags;
	if(Index < 0)
		return 0;
	if (Index == TILE_CP || Index == TILE_CP_F)
		return Index;
	else
		return 0;
}

vec2 CCollision::CpSpeed(int Index, int Flags)
{
	if(Index < 0)
		return vec2(0,0);
	vec2 target;
	if(Index == TILE_CP || Index == TILE_CP_F)
		switch(Flags)
		{
		case ROTATION_0:
			target.x=0;
			target.y=-4;
			break;
		case ROTATION_90:
			target.x=4;
			target.y=0;
			break;
		case ROTATION_180:
			target.x=0;
			target.y=4;
			break;
		case ROTATION_270:
			target.x=-4;
			target.y=0;
			break;
		default:
			target=vec2(0,0);
			break;
		}
	if(Index == TILE_CP_F)
       target*=4;
   return target;
}

int CCollision::GetPureMapIndex(vec2 Pos)
{
	int Nx = clamp((int)Pos.x/32, 0, m_Width-1);
	int Ny = clamp((int)Pos.y/32, 0, m_Height-1);
	return Ny*m_Width+Nx;
}

bool CCollision::TileExists(int Index)
{
	if(Index < 0)
		return false;

	if(m_pTiles[Index].m_Index >= TILE_FREEZE && m_pTiles[Index].m_Index <= TILE_NPH)
		return true;
	if(m_pFront && m_pFront[Index].m_Index >= TILE_FREEZE && m_pFront[Index].m_Index  <= TILE_NPH)
		return true;
	if(m_pTele && (m_pTele[Index].m_Type == TILE_TELEIN || m_pTele[Index].m_Type == TILE_TELEINEVIL || m_pTele[Index].m_Type == TILE_TELECHECK || m_pTele[Index].m_Type == TILE_TELECHECKIN))
		return true;
	if(m_pSpeedup && m_pSpeedup[Index].m_Force > 0)
		return true;
	if(m_pDoor && m_pDoor[Index].m_Index)
		return true;
	if(m_pSwitch && m_pSwitch[Index].m_Type)
		return true;
	return TileExistsNext(Index);
}

bool CCollision::TileExistsNext(int Index)
{
	if(Index < 0)
		return false;
	int TileOnTheLeft = (Index - 1 > 0) ? Index - 1 : Index;
	int TileOnTheRight = (Index + 1 < m_Width * m_Height) ? Index + 1 : Index;
	int TileBelow = (Index + m_Width < m_Width * m_Height) ? Index + m_Width : Index;
	int TileAbove = (Index - m_Width > 0) ? Index - m_Width : Index;

	if((m_pTiles[TileOnTheRight].m_Index == TILE_STOP && m_pTiles[TileOnTheRight].m_Flags == ROTATION_270) || (m_pTiles[TileOnTheLeft].m_Index == TILE_STOP && m_pTiles[TileOnTheLeft].m_Flags == ROTATION_90))
		return true;
	if((m_pTiles[TileBelow].m_Index == TILE_STOP && m_pTiles[TileBelow].m_Flags == ROTATION_0) || (m_pTiles[TileAbove].m_Index == TILE_STOP && m_pTiles[TileAbove].m_Flags == ROTATION_180))
		return true;
	if(m_pTiles[TileOnTheRight].m_Index == TILE_STOPA || m_pTiles[TileOnTheLeft].m_Index == TILE_STOPA || ((m_pTiles[TileOnTheRight].m_Index == TILE_STOPS || m_pTiles[TileOnTheLeft].m_Index == TILE_STOPS) && m_pTiles[TileOnTheRight].m_Flags|ROTATION_270|ROTATION_90))
		return true;
	if(m_pTiles[TileBelow].m_Index == TILE_STOPA || m_pTiles[TileAbove].m_Index == TILE_STOPA || ((m_pTiles[TileBelow].m_Index == TILE_STOPS || m_pTiles[TileAbove].m_Index == TILE_STOPS) && m_pTiles[TileBelow].m_Flags|ROTATION_180|ROTATION_0))
		return true;
	if(m_pFront)
	{
		if(m_pFront[TileOnTheRight].m_Index == TILE_STOPA || m_pFront[TileOnTheLeft].m_Index == TILE_STOPA || ((m_pFront[TileOnTheRight].m_Index == TILE_STOPS || m_pFront[TileOnTheLeft].m_Index == TILE_STOPS) && m_pFront[TileOnTheRight].m_Flags|ROTATION_270|ROTATION_90))
			return true;
		if(m_pFront[TileBelow].m_Index == TILE_STOPA || m_pFront[TileAbove].m_Index == TILE_STOPA || ((m_pFront[TileBelow].m_Index == TILE_STOPS || m_pFront[TileAbove].m_Index == TILE_STOPS) && m_pFront[TileBelow].m_Flags|ROTATION_180|ROTATION_0))
			return true;
		if((m_pFront[TileOnTheRight].m_Index == TILE_STOP && m_pFront[TileOnTheRight].m_Flags == ROTATION_270) || (m_pFront[TileOnTheLeft].m_Index == TILE_STOP && m_pFront[TileOnTheLeft].m_Flags == ROTATION_90))
			return true;
		if((m_pFront[TileBelow].m_Index == TILE_STOP && m_pFront[TileBelow].m_Flags == ROTATION_0) || (m_pFront[TileAbove].m_Index == TILE_STOP && m_pFront[TileAbove].m_Flags == ROTATION_180))
			return true;
	}
	if(m_pDoor)
	{
		if(m_pDoor[TileOnTheRight].m_Index == TILE_STOPA || m_pDoor[TileOnTheLeft].m_Index == TILE_STOPA || ((m_pDoor[TileOnTheRight].m_Index == TILE_STOPS || m_pDoor[TileOnTheLeft].m_Index == TILE_STOPS) && m_pDoor[TileOnTheRight].m_Flags|ROTATION_270|ROTATION_90))
			return true;
		if(m_pDoor[TileBelow].m_Index == TILE_STOPA || m_pDoor[TileAbove].m_Index == TILE_STOPA || ((m_pDoor[TileBelow].m_Index == TILE_STOPS || m_pDoor[TileAbove].m_Index == TILE_STOPS) && m_pDoor[TileBelow].m_Flags|ROTATION_180|ROTATION_0))
			return true;
		if((m_pDoor[TileOnTheRight].m_Index == TILE_STOP && m_pDoor[TileOnTheRight].m_Flags == ROTATION_270) || (m_pDoor[TileOnTheLeft].m_Index == TILE_STOP && m_pDoor[TileOnTheLeft].m_Flags == ROTATION_90))
			return true;
		if((m_pDoor[TileBelow].m_Index == TILE_STOP && m_pDoor[TileBelow].m_Flags == ROTATION_0) || (m_pDoor[TileAbove].m_Index == TILE_STOP && m_pDoor[TileAbove].m_Flags == ROTATION_180))
			return true;
	}
	return false;
}

int CCollision::GetMapIndex(vec2 Pos)
{
	int Nx = clamp((int)Pos.x / 32, 0, m_Width - 1);
	int Ny = clamp((int)Pos.y / 32, 0, m_Height - 1);
	int Index = Ny*m_Width+Nx;
	/*if (m_pTele && (m_pTele[Index].m_Type == TILE_TELEIN)) dbg_msg("m_pTele && TELEIN","Index %d",Index);
	else if (m_pTele && m_pTele[Index].m_Type==TILE_TELEOUT) dbg_msg("TELEOUT","Index %d",Index);
	else dbg_msg("GetMapIndex(","Index %d",Index);//REMOVE */

	if(TileExists(Index))
		return Index;
	else
		return -1;
}

std::list<int> CCollision::GetMapIndices(vec2 PrevPos, vec2 Pos, unsigned MaxIndices)
{
	std::list< int > Indices;
	float d = distance(PrevPos, Pos);
	int End(d + 1);
	if(!d)
	{
		int Nx = clamp((int)Pos.x / 32, 0, m_Width - 1);
		int Ny = clamp((int)Pos.y / 32, 0, m_Height - 1);
		int Index = Ny * m_Width + Nx;
		/*if (m_pTele && (m_pTele[Index].m_Type == TILE_TELEIN)) dbg_msg("m_pTele && TELEIN","Index %d",Index);
		else if (m_pTele && m_pTele[Index].m_Type==TILE_TELEOUT) dbg_msg("TELEOUT","Index %d",Index);
		else dbg_msg("GetMapIndex(","Index %d",Index);//REMOVE */

		if(TileExists(Index))
		{
			Indices.push_back(Index);
			return Indices;
		}
		else
			return Indices;
	}
	else
	{
		float a = 0.0f;
		vec2 Tmp = vec2(0, 0);
		int Nx = 0;
		int Ny = 0;
		int Index,LastIndex = 0;
		for(int i = 0; i < End; i++)
		{
			a = i/d;
			Tmp = mix(PrevPos, Pos, a);
			Nx = clamp((int)Tmp.x / 32, 0, m_Width - 1);
			Ny = clamp((int)Tmp.y / 32, 0, m_Height - 1);
			Index = Ny * m_Width + Nx;
			//dbg_msg("lastindex","%d",LastIndex);
			//dbg_msg("index","%d",Index);
			if(TileExists(Index) && LastIndex != Index)
			{
				if(MaxIndices && Indices.size() > MaxIndices)
					return Indices;
				Indices.push_back(Index);
				LastIndex = Index;
				//dbg_msg("pushed","%d",Index);
			}
		}

		return Indices;
	}
}

vec2 CCollision::GetPos(int Index)
{
	if(Index < 0)
		return vec2(0,0);

	int x = Index%m_Width;
	int y = Index/m_Width;
	return vec2(x*32+16, y*32+16);
}

int CCollision::GetTileIndex(int Index)
{
	/*dbg_msg("GetTileIndex","m_pTiles[%d].m_Index = %d",Index,m_pTiles[Index].m_Index);//Remove*/
	if(Index < 0)
		return 0;
	return m_pTiles[Index].m_Index;
}

int CCollision::GetFTileIndex(int Index)
{
	/*dbg_msg("GetFTileIndex","m_pFront[%d].m_Index = %d",Index,m_pFront[Index].m_Index);//Remove*/

	if(Index < 0 || !m_pFront)
		return 0;
	return m_pFront[Index].m_Index;
}

int CCollision::GetTileFlags(int Index)
{
	/*dbg_msg("GetTileIndex","m_pTiles[%d].m_Index = %d",Index,m_pTiles[Index].m_Index);//Remove*/
	if(Index < 0)
		return 0;
	return m_pTiles[Index].m_Flags;
}

int CCollision::GetFTileFlags(int Index)
{
	/*dbg_msg("GetFTileIndex","m_pFront[%d].m_Index = %d",Index,m_pFront[Index].m_Index);//Remove*/

	if(Index < 0 || !m_pFront)
		return 0;
	return m_pFront[Index].m_Flags;
}

int CCollision::GetIndex(int Nx, int Ny)
{
	return m_pTiles[Ny*m_Width+Nx].m_Index;
}

int CCollision::GetFIndex(int Nx, int Ny)
{
	if(!m_pFront) return 0;
	return m_pFront[Ny*m_Width+Nx].m_Index;
}

int CCollision::GetFTile(int x, int y)
{
	if(!m_pFront)
	return 0;
	int Nx = clamp(x/32, 0, m_Width-1);
	int Ny = clamp(y/32, 0, m_Height-1);
	/*dbg_msg("GetFTile","m_Index %d",m_pFront[Ny*m_Width+Nx].m_Index);//Remove */
	if(m_pFront[Ny*m_Width+Nx].m_Index == COLFLAG_DEATH
		|| m_pFront[Ny*m_Width+Nx].m_Index == COLFLAG_NOLASER)
		return m_pFront[Ny*m_Width+Nx].m_Index;
	else
		return 0;
}

int CCollision::Entity(int x, int y, int Layer)
{
	if((0 > x || x >= m_Width) || (0 > y || y >= m_Height))
	{
		char aBuf[12];
		switch (Layer)
		{
			case LAYER_GAME:
				str_format(aBuf,sizeof(aBuf), "Game");
				break;
			case LAYER_FRONT:
				str_format(aBuf,sizeof(aBuf), "Front");
				break;
			case LAYER_SWITCH:
				str_format(aBuf,sizeof(aBuf), "Switch");
				break;
			case LAYER_TELE:
				str_format(aBuf,sizeof(aBuf), "Tele");
				break;
			case LAYER_SPEEDUP:
				str_format(aBuf,sizeof(aBuf), "Speedup");
				break;
			default:
				str_format(aBuf,sizeof(aBuf), "Unknown");
		}
		dbg_msg("CCollision::Entity","Something is VERY wrong with the %s layer please report this at http://DDRace.info, you will need to post the map as well and aNy steps that u think may have led to this, Please Also Read the News Section every once and a while", aBuf);
		return 0;
	}
	switch (Layer)
	{
		case LAYER_GAME:
			return m_pTiles[y*m_Width+x].m_Index - ENTITY_OFFSET;
		case LAYER_FRONT:
			return m_pFront[y*m_Width+x].m_Index - ENTITY_OFFSET;
		case LAYER_SWITCH:
			return m_pSwitch[y*m_Width+x].m_Type - ENTITY_OFFSET;
		case LAYER_TELE:
			return m_pTele[y*m_Width+x].m_Type - ENTITY_OFFSET;
		case LAYER_SPEEDUP:
			return m_pSpeedup[y*m_Width+x].m_Type - ENTITY_OFFSET;
		default:
			return 0;
			break;
	}
}

void CCollision::SetCollisionAt(float x, float y, int flag)
{
   int Nx = clamp(round(x)/32, 0, m_Width-1);
   int Ny = clamp(round(y)/32, 0, m_Height-1);

   m_pTiles[Ny * m_Width + Nx].m_Index = flag;
}

void CCollision::SetDCollisionAt(float x, float y, int Type, int Flags, int Number)
{
	if(!m_pDoor)
		return;
   int Nx = clamp(round(x)/32, 0, m_Width-1);
   int Ny = clamp(round(y)/32, 0, m_Height-1);

   m_pDoor[Ny * m_Width + Nx].m_Index = Type;
   m_pDoor[Ny * m_Width + Nx].m_Flags = Flags;
   m_pDoor[Ny * m_Width + Nx].m_Number = Number;
}

int CCollision::GetDTileIndex(int Index)
{
	if(!m_pDoor || Index < 0 || !m_pDoor[Index].m_Index)
		return 0;
	return m_pDoor[Index].m_Index;
}

int CCollision::GetDTileNumber(int Index)
{
	if(!m_pDoor || Index < 0 || !m_pDoor[Index].m_Index)
		return 0;
	if(m_pDoor[Index].m_Number) return m_pDoor[Index].m_Number;
	return 0;
}

int CCollision::GetDTileFlags(int Index)
{
	if(!m_pDoor || Index < 0 || !m_pDoor[Index].m_Index)
		return 0;
	return m_pDoor[Index].m_Flags;
}

void ThroughOffset(vec2 Pos0, vec2 Pos1, int *Ox, int *Oy)
{
	float x = Pos0.x - Pos1.x;
	float y = Pos0.y - Pos1.y;
	if (fabs(x) > fabs(y))
	{
		if (x < 0)
		{
			*Ox = -32;
			*Oy = 0;
		}
		else
		{
			*Ox = 32;
			*Oy = 0;
		}
	}
	else
	{
		if (y < 0)
		{
			*Ox = 0;
			*Oy = -32;
		}
		else
		{
			*Ox = 0;
			*Oy = 32;
		}
	}
}

int CCollision::IntersectNoLaser(vec2 Pos0, vec2 Pos1, vec2 *pOutCollision, vec2 *pOutBeforeCollision)
{
	float d = distance(Pos0, Pos1);
	vec2 Last = Pos0;

	for(float f = 0; f < d; f++)
	{
		float a = f/d;
		vec2 Pos = mix(Pos0, Pos1, a);
		int Nx = clamp(round(Pos.x)/32, 0, m_Width-1);
		int Ny = clamp(round(Pos.y)/32, 0, m_Height-1);
		if(GetIndex(Nx, Ny) == COLFLAG_SOLID
			|| GetIndex(Nx, Ny) == (COLFLAG_SOLID|COLFLAG_NOHOOK)
			|| GetIndex(Nx, Ny) == COLFLAG_NOLASER
			|| GetFIndex(Nx, Ny) == COLFLAG_NOLASER)
		{
			if(pOutCollision)
				*pOutCollision = Pos;
			if(pOutBeforeCollision)
				*pOutBeforeCollision = Last;
			if (GetFIndex(Nx, Ny) == COLFLAG_NOLASER)	return GetFCollisionAt(Pos.x, Pos.y);
			else return GetCollisionAt(Pos.x, Pos.y);

		}
		Last = Pos;
	}
	if(pOutCollision)
		*pOutCollision = Pos1;
	if(pOutBeforeCollision)
		*pOutBeforeCollision = Pos1;
	return 0;
}

int CCollision::IntersectNoLaserNW(vec2 Pos0, vec2 Pos1, vec2 *pOutCollision, vec2 *pOutBeforeCollision)
{
	float d = distance(Pos0, Pos1);
	vec2 Last = Pos0;

	for(float f = 0; f < d; f++)
	{
		float a = f/d;
		vec2 Pos = mix(Pos0, Pos1, a);
		if(IsNoLaser(round(Pos.x), round(Pos.y)) || IsFNoLaser(round(Pos.x), round(Pos.y)))
		{
			if(pOutCollision)
				*pOutCollision = Pos;
			if(pOutBeforeCollision)
				*pOutBeforeCollision = Last;
			if(IsNoLaser(round(Pos.x), round(Pos.y))) return GetCollisionAt(Pos.x, Pos.y);
			else return  GetFCollisionAt(Pos.x, Pos.y);
		}
		Last = Pos;
	}
	if(pOutCollision)
		*pOutCollision = Pos1;
	if(pOutBeforeCollision)
		*pOutBeforeCollision = Pos1;
	return 0;
}

int CCollision::IntersectAir(vec2 Pos0, vec2 Pos1, vec2 *pOutCollision, vec2 *pOutBeforeCollision)
{
	float d = distance(Pos0, Pos1);
	vec2 Last = Pos0;

	for(float f = 0; f < d; f++)
	{
		float a = f/d;
		vec2 Pos = mix(Pos0, Pos1, a);
		if(IsSolid(round(Pos.x), round(Pos.y)) || (!GetTile(round(Pos.x), round(Pos.y)) && !GetFTile(round(Pos.x), round(Pos.y))))
		{
			if(pOutCollision)
				*pOutCollision = Pos;
			if(pOutBeforeCollision)
				*pOutBeforeCollision = Last;
			if(!GetTile(round(Pos.x), round(Pos.y)) && !GetFTile(round(Pos.x), round(Pos.y)))
				return -1;
			else
				if (!GetTile(round(Pos.x), round(Pos.y))) return GetTile(round(Pos.x), round(Pos.y));
				else return GetFTile(round(Pos.x), round(Pos.y));
		}
		Last = Pos;
	}
	if(pOutCollision)
		*pOutCollision = Pos1;
	if(pOutBeforeCollision)
		*pOutBeforeCollision = Pos1;
	return 0;
}

int CCollision::IsCheckpoint(int Index)
{
	if(Index < 0)
		return -1;

	int z = m_pTiles[Index].m_Index;
	if(z >= 35 && z <= 59)
		return z-35;
	return -1;
}

int CCollision::IsFCheckpoint(int Index)
{
	if(Index < 0 || !m_pFront)
		return -1;

	int z = m_pFront[Index].m_Index;
	if(z >= 35 && z <= 59)
		return z-35;
	return -1;
}