public Cell(CoordPair p)
{
grid_x = p.x_coord / MapConst.MAX_NUMBER_OF_CELLS;
grid_y = p.y_coord / MapConst.MAX_NUMBER_OF_CELLS;
cell_x = p.x_coord % MapConst.MAX_NUMBER_OF_CELLS;
cell_y = p.y_coord % MapConst.MAX_NUMBER_OF_CELLS;
nocreate = false;
//reserved = 0;
}
public Cell(float x, float y)
{
CoordPair p = GridDefines.ComputeCellCoord(x, y);
grid_x = p.x_coord / MapConst.MAX_NUMBER_OF_CELLS;
grid_y = p.y_coord / MapConst.MAX_NUMBER_OF_CELLS;
cell_x = p.x_coord % MapConst.MAX_NUMBER_OF_CELLS;
cell_y = p.y_coord % MapConst.MAX_NUMBER_OF_CELLS;
nocreate = false;
//reserved = 0;
}
void VisitCircle <T>(Visitor <T> visitor, Map map, CoordPair begin_cell, CoordPair end_cell) where T : Notifier
{
//here is an algorithm for 'filling' circum-squared octagon
uint x_shift = (uint)Math.Ceiling((end_cell.x_coord - begin_cell.x_coord) * 0.3f - 0.5f);
//lets calculate x_start/x_end coords for central strip...
uint x_start = begin_cell.x_coord + x_shift;
uint x_end = end_cell.x_coord - x_shift;
//visit central strip with constant width...
for (uint x = x_start; x <= x_end; ++x)
{
for (uint y = begin_cell.y_coord; y <= end_cell.y_coord; ++y)
{
CellCoord cellCoord = new CellCoord(x, y);
Cell r_zone = new Cell(cellCoord);
r_zone.nocreate = this.nocreate;
map.Visit(r_zone, visitor);
}
}
//if x_shift == 0 then we have too small cell area, which were already
//visited at previous step, so just return from procedure...
if (x_shift == 0)
{
return;
}
uint y_start = end_cell.y_coord;
uint y_end = begin_cell.y_coord;
//now we are visiting borders of an octagon...
for (uint step = 1; step <= (x_start - begin_cell.x_coord); ++step)
{
//each step reduces strip height by 2 cells...
y_end += 1;
y_start -= 1;
for (uint y = y_start; y >= y_end; --y)
{
//we visit cells symmetrically from both sides, heading from center to sides and from up to bottom
//e.g. filling 2 trapezoids after filling central cell strip...
CellCoord cellCoord_left = new CellCoord(x_start - step, y);
Cell r_zone_left = new Cell(cellCoord_left);
r_zone_left.nocreate = this.nocreate;
map.Visit(r_zone_left, visitor);
//right trapezoid cell visit
CellCoord cellCoord_right = new CellCoord(x_end + step, y);
Cell r_zone_right = new Cell(cellCoord_right);
r_zone_right.nocreate = this.nocreate;
map.Visit(r_zone_right, visitor);
}
}
}
public CellArea(float x, float y, float radius)
{
if (radius <= 0.0f)
{
CoordPair center = GridDefines.ComputeCellCoord(x, y).normalize();
low_bound = center;
high_bound = center;
return;
}
CoordPair centerX = GridDefines.ComputeCellCoord(x - radius, y - radius).normalize();
CoordPair centerY = GridDefines.ComputeCellCoord(x + radius, y + radius).normalize();
low_bound = centerX;
high_bound = centerY;
}
void ResizeBorders(CoordPair begin_cell, CoordPair end_cell)
{
begin_cell = low_bound;
end_cell = high_bound;
}
public void Visit <T>(CoordPair standing_cell, Visitor <T> visitor, Map map, float radius, float x_off, float y_off) where T : Notifier
{
if (!standing_cell.IsCoordValid())
{
return;
}
//no jokes here... Actually placing ASSERT() here was good idea, but
//we had some problems with DynamicObjects, which pass radius = 0.0f (DB issue?)
//maybe it is better to just return when radius <= 0.0f?
if (radius <= 0.0f)
{
map.Visit(this, visitor);
return;
}
//lets limit the upper value for search radius
if (radius > MapConst.SizeOfGrids)
{
radius = MapConst.SizeOfGrids;
}
//lets calculate object coord offsets from cell borders.
CellArea area = new CellArea(x_off, y_off, radius);
//if radius fits inside standing cell
if (area == null)
{
map.Visit(this, visitor);
return;
}
//visit all cells, found in CalculateCellArea()
//if radius is known to reach cell area more than 4x4 then we should call optimized VisitCircle
//currently this technique works with MAX_NUMBER_OF_CELLS 16 and higher, with lower values
//there are nothing to optimize because SIZE_OF_GRID_CELL is too big...
if ((area.high_bound.x_coord > (area.low_bound.x_coord + 4)) && (area.high_bound.y_coord > (area.low_bound.y_coord + 4)))
{
VisitCircle(visitor, map, area.low_bound, area.high_bound);
return;
}
//ALWAYS visit standing cell first!!! Since we deal with small radiuses
//it is very essential to call visitor for standing cell firstly...
map.Visit(this, visitor);
// loop the cell range
for (uint x = area.low_bound.x_coord; x <= area.high_bound.x_coord; ++x)
{
for (uint y = area.low_bound.y_coord; y <= area.high_bound.y_coord; ++y)
{
CellCoord cellCoord = new CellCoord(x, y);
//lets skip standing cell since we already visited it
if (cellCoord != standing_cell)
{
Cell r_zone = new Cell(cellCoord);
r_zone.nocreate = this.nocreate;
map.Visit(r_zone, visitor);
}
}
}
}
public CoordPair(CoordPair obj)
{
Limit = obj.Limit;
x_coord = obj.x_coord;
y_coord = obj.y_coord;
}