// Generate an octant of shadows, and return the FOV area to be redrawn
private static List <Cell> ShadowOctant(Level level, Vector2Int origin,
int octant)
{
// Increments based off of octantCoordinates
var rowInc = _octantCoords[octant, 0];
var colInc = _octantCoords[octant, 1];
ShadowLine line = new ShadowLine();
bool fullShadow = false;
List <Cell> ret = new List <Cell>();
for (int row = 0; row < FOVRadius; row++)
{
// Record position
Vector2Int pos = origin + (rowInc * row);
// Stop once going out of bounds
if (!level.Contains(pos))
{
break;
}
bool pastMaxDistance = false;
for (int col = 0; col <= row; col++)
{
// Break on this row if going out of bounds
if (!level.Contains(pos))
{
break;
}
// Visibility fall off over distance
int fallOff = 255;
// If entire row is known to be in shadow, set this cell to
// be in shadow
if (fullShadow || pastMaxDistance)
{
Cell c = level.GetCell(pos);
if (c.SetVisibility(false, fallOff))
{
ret.Add(c);
}
}
else
{
float distance = Vector2.Distance(origin, pos);
if (distance > FOVRadius)
{
fallOff = 255;
pastMaxDistance = true;
}
else
{
float normalized = distance / FOVRadius;
normalized = Mathf.Pow(normalized, 2);
fallOff = (int)(normalized * 255);
}
Shadow projection = ProjectTile(row, col);
// Set the visibility of this tile
bool visible = !line.IsInShadow(projection);
Cell c = level.GetCell(pos);
if (c.SetVisibility(visible, fallOff))
{
ret.Add(c);
}
// Add any opaque tiles to the shadow map
if (visible && level.GetCell(pos).Opaque)
{
line.AddShadow(projection);
fullShadow = line.IsFullShadow();
}
}
pos += colInc;
if (!level.Contains(pos))
{
break;
}
}
}
return(ret);
}
public bool Contains(Shadow other) => Start <= other.Start && End >= other.End;