public TrackHistory(int x, int y, TrackSlope slope)
{
X = (short)x;
Y = (short)y;
Slope = slope;
Mode = TrackMode.Normal;
}
private static bool CanSlopesTouch(TrackSlope leftSlope, TrackSlope rightSlope)
{
if (leftSlope != rightSlope && leftSlope != 0)
{
return(rightSlope == TrackSlope.Straight);
}
return(true);
}
private void RewriteSlopeDirection(int index, TrackSlope slope)
{
int num = slope - _history[index].Slope;
_history[index].Slope = slope;
for (int i = index; i < _length; i++)
{
_history[i].Y += (short)num;
}
}
private TrackPlacementState CreateTunnel()
{
TrackSlope trackSlope = TrackSlope.Straight;
int num = 10;
TrackPlacementState trackPlacementState = TrackPlacementState.Invalid;
int x = _history[_length - 1].X;
int y = _history[_length - 1].Y;
for (TrackSlope trackSlope2 = TrackSlope.Up; trackSlope2 <= TrackSlope.Down; trackSlope2++)
{
TrackPlacementState trackPlacementState2 = TrackPlacementState.Invalid;
for (int i = 1; i < num; i++)
{
trackPlacementState2 = CalculateStateForLocation(x + i * _xDirection, y + i * (int)trackSlope2);
switch (trackPlacementState2)
{
default:
trackSlope = trackSlope2;
num = i;
trackPlacementState = trackPlacementState2;
break;
case TrackPlacementState.Obstructed:
continue;
case TrackPlacementState.Invalid:
break;
}
break;
}
if (trackPlacementState != 0 && trackPlacementState2 == TrackPlacementState.Obstructed && (trackPlacementState != TrackPlacementState.Obstructed || trackSlope != 0))
{
trackSlope = trackSlope2;
num = 10;
trackPlacementState = trackPlacementState2;
}
}
if (_length == 0 || !CanSlopesTouch(_history[_length - 1].Slope, trackSlope))
{
RewriteSlopeDirection(_length - 1, TrackSlope.Straight);
}
_history[_length - 1].Mode = TrackMode.Tunnel;
for (int j = 1; j < num; j++)
{
AppendToHistory(trackSlope, TrackMode.Tunnel);
}
return(trackPlacementState);
}
private bool FindPath(int minLength, int maxLength)
{
int length = _length;
while (_length < _history.Length - 100)
{
TrackSlope slope = (_history[_length - 1].Slope != TrackSlope.Up) ? TrackSlope.Down : TrackSlope.Straight;
AppendToHistory(slope);
TrackPlacementState trackPlacementState = TryRewriteHistoryToAvoidTiles();
if (trackPlacementState == TrackPlacementState.Invalid)
{
break;
}
length = _length;
TrackPlacementState trackPlacementState2 = trackPlacementState;
while (trackPlacementState2 != 0)
{
trackPlacementState2 = CreateTunnel();
if (trackPlacementState2 == TrackPlacementState.Invalid)
{
break;
}
length = _length;
}
if (_length >= maxLength)
{
break;
}
}
_length = Math.Min(maxLength, length);
if (_length < minLength)
{
return(false);
}
SmoothTrack();
return(GetHistorySegmentPlacementState(0, _length) != TrackPlacementState.Invalid);
}
private void AppendToHistory(TrackSlope slope, TrackMode mode = TrackMode.Normal)
{
_history[_length] = new TrackHistory(_history[_length - 1].X + _xDirection, (int)_history[_length - 1].Y + (int)slope, slope);
_history[_length].Mode = mode;
_length++;
}
