///<summary>Build reverted route of player moving to specific cell (x,y of destination, route to add, build short tree or full)</summary>
private MoveResult PlayerTravelRoute(int iXdest, int iYdest, SokobanGame uRoute, bool bUseShortTree)
{
if (iPlayerX == iXdest && iPlayerY == iYdest)
return MoveResult.Moved;//Player already there - nothing to do
if (bUseShortTree)
{//Using short tree - only to reach destination
BuildPlayerMoveTree_UpTo(iPlayerX, iPlayerY, iXdest, iYdest);
}
else
{//Using full tree - for all level
BuildPlayerMoveTree(iPlayerX, iPlayerY);
}
int iMoveLen = iMoveTree[iXdest, iYdest];
if (iMoveLen < 0)
return MoveResult.WayBlocked;//Negative values - destination unreachable
//Building reverted route from destination to start
int x = iXdest; int y = iYdest;
int iValue = iMoveLen;
while (iValue > 0)
{//Find nearest cell thet have value less then iValue and move player there
if (iMoveTree[x - 1, y] >= 0 && iMoveTree[x - 1, y] < iValue) { iValue = iMoveTree[x - 1, y]; uRoute.AddNextRevertedMove(SokoMove.Right); x--; continue; }
if (iMoveTree[x + 1, y] >= 0 && iMoveTree[x + 1, y] < iValue) { iValue = iMoveTree[x + 1, y]; uRoute.AddNextRevertedMove(SokoMove.Left); x++; continue; }
if (iMoveTree[x, y - 1] >= 0 && iMoveTree[x, y - 1] < iValue) { iValue = iMoveTree[x, y - 1]; uRoute.AddNextRevertedMove(SokoMove.Down); y--; continue; }
if (iMoveTree[x, y + 1] >= 0 && iMoveTree[x, y + 1] < iValue) { iValue = iMoveTree[x, y + 1]; uRoute.AddNextRevertedMove(SokoMove.Up); y++; continue; }
return MoveResult.WayBlocked;//Failed to travel (something very wrong)
}
return MoveResult.Moved;
}
///<summary>Build reverted route of box pushing to specific cell (x,y of destination, route to add)</summary>
private MoveResult BoxTravelRoute(int iXdest, int iYdest, SokobanGame uRoute)
{
//Box move tree must be build before calling
int z;
int iDir = -1, iDirPre;
MoveResult uRv;
//Matrix of paths
short[,] iMatrix = new short[4, 4];
iMatrix[PLAYER_TO_DOWN, PLAYER_TO_DOWN] = 0;
iMatrix[PLAYER_TO_DOWN, PLAYER_TO_LEFT] = BMTF_DOWN_TO_LEFT;
iMatrix[PLAYER_TO_DOWN, PLAYER_TO_RIGHT] = BMTF_DOWN_TO_RIGHT;
iMatrix[PLAYER_TO_DOWN, PLAYER_TO_UP] = BMTF_UP_TO_DOWN;
iMatrix[PLAYER_TO_LEFT, PLAYER_TO_DOWN] = BMTF_DOWN_TO_LEFT;
iMatrix[PLAYER_TO_LEFT, PLAYER_TO_LEFT] = 0;
iMatrix[PLAYER_TO_LEFT, PLAYER_TO_RIGHT] = BMTF_LEFT_TO_RIGHT;
iMatrix[PLAYER_TO_LEFT, PLAYER_TO_UP] = BMTF_UP_TO_LEFT;
iMatrix[PLAYER_TO_RIGHT, PLAYER_TO_DOWN] = BMTF_DOWN_TO_RIGHT;
iMatrix[PLAYER_TO_RIGHT, PLAYER_TO_LEFT] = BMTF_LEFT_TO_RIGHT;
iMatrix[PLAYER_TO_RIGHT, PLAYER_TO_RIGHT] = 0;
iMatrix[PLAYER_TO_RIGHT, PLAYER_TO_UP] = BMTF_UP_TO_RIGHT;
iMatrix[PLAYER_TO_UP, PLAYER_TO_DOWN] = BMTF_UP_TO_DOWN;
iMatrix[PLAYER_TO_UP, PLAYER_TO_LEFT] = BMTF_UP_TO_LEFT;
iMatrix[PLAYER_TO_UP, PLAYER_TO_RIGHT] = BMTF_UP_TO_RIGHT;
iMatrix[PLAYER_TO_UP, PLAYER_TO_UP] = 0;
int x = iXdest;
int y = iYdest;
if (!IsCellAchivedByBoxMoveTree(x, y))
return MoveResult.WayBlocked; //Destination is unreachable for current box moving tree
//Find cell around destination with minimum value - there player will stop after pushing box
int iValue = short.MaxValue;
for (z = 0; z < 4; z++)
if (iBoxMoveTree[x, y, z] < iValue && iBoxMoveTree[x, y, z] >= 0)
{
iDir = z;
iValue = iBoxMoveTree[x, y, z];
}
if (iValue == 0 || iDir == -1)
{
return MoveResult.WayBlocked; //If no cell found - destination is unreachable
}
//int iMoveLen = iValue;
SokobanGame uTempLevel = new SokobanGame(this);//Create temprorary level for pathfinding
//Remove from temp-level: player and box-beeing-moved
uTempLevel.bCells[iPlayerX, iPlayerY] ^= SokoCell.Player;
uTempLevel.bCells[iBoxMoveTreeFromX, iBoxMoveTreeFromY] ^= SokoCell.Box;
//Build reverted route
lLoop1:
//Check pushing box
switch (iDir)
{
case PLAYER_TO_DOWN:
y++;//Player to down, so he push box to up to reach this state
if (iBoxMoveTree[x, y, iDir] > iValue || iBoxMoveTree[x, y, iDir] < 0)
{//Player is on cell with incorrect value, something wrong or route is completed
y--;//Return player
goto lEnd;//Exit building route
}
uRoute.AddNextRevertedMove(SokoMove.Up | SokoMove.Push);//Add push-to-up to reverted route
break;
case PLAYER_TO_UP://By analogue...
y--;
if (iBoxMoveTree[x, y, iDir] > iValue || iBoxMoveTree[x, y, iDir] < 0)
{
y++;
goto lEnd;
}
uRoute.AddNextRevertedMove(SokoMove.Down | SokoMove.Push);
break;
case PLAYER_TO_LEFT:
x--;
if (iBoxMoveTree[x, y, iDir] > iValue || iBoxMoveTree[x, y, iDir] < 0)
{
x++;
goto lEnd;
}
uRoute.AddNextRevertedMove(SokoMove.Right | SokoMove.Push);
break;
case PLAYER_TO_RIGHT:
x++;
if (iBoxMoveTree[x, y, iDir] > iValue || iBoxMoveTree[x, y, iDir] < 0)
{
x--;
goto lEnd;
}
uRoute.AddNextRevertedMove(SokoMove.Left | SokoMove.Push);
break;
default://Unknown direction - something wrong
goto lEnd;
}
if (x == iBoxMoveTreeFromX && y == iBoxMoveTreeFromY)
{//Box is in place - root of box move tree
if (bBoxMoveTreeRootDirections[iDir])
{ //This location of player is reachable from start
goto lEnd;
}
}
iValue = iBoxMoveTree[x, y, iDir];//Update value to current box-move-tree cell (added 20.10.2008 to fix bug with additional moves after reaching box)
iDirPre = iDir;//Store direction of pushing to compare later
//Find cell around box with lesser value on box-move-tree than current - if found, player should move there (around box or by complex path) to proceed (reverted) pushing
for (z = 0; z < 4; z++)//Loop on directions
if (iBoxMoveTree[x, y, z] < iValue && iBoxMoveTree[x, y, z] >= 0)//Cell with better value (than current)
//if (z == iDirPre || (iMatrix[z, iDirPre] & iBoxMoveTree[x, y, BMT_FLAGS]) != 0)//This cell can be reached from current by moving around box (or this is current cell)
if ((iMatrix[z, iDirPre] & iBoxMoveTree[x, y, BMT_FLAGS]) != 0)//This cell can be reached from current by moving around box (current cell may not pass previous "if")
{
iDir = z;//Store new diection
iValue = iBoxMoveTree[x, y, z];//Store new value
}
if (iDir != iDirPre)
{//New direction is differ from previous - should build moving route around box (otherwise - go to pushing)
//Set box to temp. level to use pathfinding around this box
uTempLevel.bCells[x, y] ^= SokoCell.Box;
uRv = MoveResult.WayBlocked;
uTempLevel.InvalidatePlayerMoveTree();//Flush player move tree
//Set player location for start of path finding - new cell near box
uTempLevel.iPlayerX = x; uTempLevel.iPlayerY = y;
switch (iDir)
{
case PLAYER_TO_DOWN: uTempLevel.iPlayerY++; break;
case PLAYER_TO_UP: uTempLevel.iPlayerY--; break;
case PLAYER_TO_LEFT: uTempLevel.iPlayerX--; break;
case PLAYER_TO_RIGHT: uTempLevel.iPlayerX++; break;
}
//Find path from new cell to previous
switch (iDirPre)
{
case PLAYER_TO_DOWN: uRv = uTempLevel.PlayerTravelRoute(x, y + 1, uRoute, true); break;
case PLAYER_TO_UP: uRv = uTempLevel.PlayerTravelRoute(x, y - 1, uRoute, true); break;
case PLAYER_TO_LEFT: uRv = uTempLevel.PlayerTravelRoute(x - 1, y, uRoute, true); break;
case PLAYER_TO_RIGHT: uRv = uTempLevel.PlayerTravelRoute(x + 1, y, uRoute, true); break;
}
//If no path - something wrong
if (uRv == MoveResult.WayBlocked)
return uRv;
//Remove box
uTempLevel.bCells[x, y] ^= SokoCell.Box;
}
goto lLoop1;//Go to next push
lEnd:
if (x != iBoxMoveTreeFromX || y != iBoxMoveTreeFromY)
return MoveResult.WayBlocked; //if box not reach root of tree - path not builded
//Need to find path for player to box
//Set box to temp. level to use pathfinding around this box
uTempLevel.bCells[x, y] ^= SokoCell.Box;
uRv = MoveResult.WayBlocked;
uTempLevel.InvalidatePlayerMoveTree();//Flush player move tree
uTempLevel.iPlayerX = iPlayerX; uTempLevel.iPlayerY = iPlayerY;//Set player start location - get it from actual level
switch (iDir)//Find path
{
case PLAYER_TO_DOWN: uRv = uTempLevel.PlayerTravelRoute(x, y + 1, uRoute, true); break;
case PLAYER_TO_UP: uRv = uTempLevel.PlayerTravelRoute(x, y - 1, uRoute, true); break;
case PLAYER_TO_LEFT: uRv = uTempLevel.PlayerTravelRoute(x - 1, y, uRoute, true); break;
case PLAYER_TO_RIGHT: uRv = uTempLevel.PlayerTravelRoute(x + 1, y, uRoute, true); break;
}
if (uRv == MoveResult.WayBlocked)
return uRv;//No path - something wring
//Reverted route builded
return MoveResult.MovedAndPushBox;
}