## Recalculating Normals Of Edited Heightmap - c#

### Issues with Steering Behavior Seperation

```The problem
I am trying to procedurally generate dungeon rooms with random X, Y sizes inside of a radius (r). However, even after I validate that the starting grid (origin of the "room") is not in the same position as other origins after running the separation function there are rooms still building inside of each other.
Solutions I have tried
I tried using math to calculate an optimal radius that will be able to fit the average of all the room sizes * amount of rooms. However, the separation should hypothetically work with any radius (though I want to keep them relatively close in order to keep hallways short).
Code
All my code is based on one tile. This means that all calculations are using one tile, and will remain one tile until the very end, then I scale them up.
private void GenerateRooms(int amount)
{
// init sizes
Vector2[] room_sizes = new Vector2[amount];
for (int i = 0; i < amount; i++)
{
room_sizes[i] = new Vector2(Random.Range(minimum_room_height, maximum_room_height), Random.Range(minimum_room_width, maximum_room_width));
}
float biggest_room = calculations.CalculateBiggest(room_sizes);
Vector2[] room_points = new Vector2[amount];
Vector2[] used_points = new Vector2[amount];
float radius = calculations.CalculateAverage(room_sizes) * amount;
for (int i = 0; i < amount; i++)
{
do {
foreach (Vector2 point in used_points) {
if (test_point == point) {
continue;
} else {
room_points[i] = test_point;
used_points[i] = test_point;
break;
}
}
} while (Vector2.Distance(Vector2.zero, room_points[i]) < radius);
}
for (int i = 0; i < amount; i++)
{
//Vector2 origin = room_points[i];
Vector3 position = calculations.computeSeperate(room_points, room_points[i], biggest_room);
//position = new Vector3(position.x + origin.x, position.y + origin.y, 0);
Vector3Int location = tile_map.WorldToCell(position);
tile_map.SetTile(location, tile);
calculations.scaleUpRooms(position, room_sizes[i].x, room_sizes[i].y, tile_map, tile);
}
}
The above is code for calling all the functions and validating the points. Here are the important functions (calculation functions):
public Vector2 computeSeperate(Vector2[] point_array, Vector2 target_point, float minimum_distance)
{
int neighbor_count = 0;
for (int i = 0; i < point_array.Length; i++)
{
if (point_array[i] != target_point)
{
if (Vector2.Distance(target_point, point_array[i]) < minimum_distance * 2)
{
target_point.x += point_array[i].x - target_point.x;
target_point.y += point_array[i].y - target_point.y;
neighbor_count++;
}
}
}
if (neighbor_count == 0)
{
return target_point;
} else
{
target_point.x /= neighbor_count;
target_point.y /= neighbor_count;
target_point.x *= -1;
target_point.y *= -1;
target_point.Normalize();
return target_point;
}
}
public void scaleUpRooms(Vector2 base_point, float scale_x, float scale_y, Tilemap tile_map, Tile tile) // ex: 5x5
{
List<Vector2> Calculate(Vector2 size)
{
List<Vector2> results = new List<Vector2>();
for (int i = 0; i < size.y; i++)
for (int o = 0; o < size.x; o++)
results.Add(new Vector2(o, i) + (new Vector2(size.x % 2 != 0 ? .5f : 1, size.y % 2 != 0 ? .5f : 1) - (size / 2)));
string st = "";
for (int i = 0; i < results.Count; i++)
st += "\n" + results[i].ToString();
return results;
}
Vector2 desired_scale = new Vector2(scale_x, scale_y);
List<Vector2> Offsets = Calculate(desired_scale);
for (int i = 0; i < Offsets.Count; i++)
{
Vector3 position = base_point + Offsets[i];
Vector3Int location = tile_map.WorldToCell(position);
tile_map.SetTile(location, tile);
}
}```

### Why does the array I pass to my multithreading job struct act as a reference type?

```I'm working on a unity project involving deformable terrain based on marching-cubes. It works by generating a map of density over the 3-dimensional coordinates of a terrain chunk and using that data to create a mesh representing the surface of the terrain. It has been working, however the process is very slow. I'm attempting to introduce multithreading to improve performance, but I've run into a problem that's left me scratching my head.
When I run CreateMeshData() and try to pass my density map terrainMap into the MarchCubeJob struct, it recognizes it as a reference type, not a value type. I've seemed to whittle down the errors to this one, but I've tried to introduce the data in every way I know how and I'm stumped. I thought passing a reference like this was supposed to create a copy of the data disconnected from the reference, but my understanding must be flawed. My goal is to pass each marchingcube cube into a job and have them run concurrently.
I'm brand new to multithreading, so I've probably made some newbie mistakes here and I'd appreciate if someone would help me out with a second look. Cheers!
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using Unity.Jobs;
using Unity.Collections;
using Unity.Burst;
public class Chunk
{
List<Vector3> vertices = new List<Vector3>();
List<int> triangles = new List<int>();
public GameObject chunkObject;
MeshFilter meshFilter;
MeshCollider meshCollider;
MeshRenderer meshRenderer;
Vector3Int chunkPosition;
public float[,,] terrainMap;
// Job system
NativeList<Vector3> marchVerts;
NativeList<Vector3> marchTris;
MarchCubeJob instanceMarchCube;
JobHandle instanceJobHandle;
int width { get { return Terrain_Data.chunkWidth;}}
int height { get { return Terrain_Data.chunkHeight;}}
static float terrainSurface { get { return Terrain_Data.terrainSurface;}}
public Chunk (Vector3Int _position){ // Constructor
chunkObject = new GameObject();
chunkObject.name = string.Format("Chunk x{0}, y{1}, z{2}", _position.x, _position.y, _position.z);
chunkPosition = _position;
chunkObject.transform.position = chunkPosition;
chunkObject.transform.tag = "Terrain";
terrainMap = new float[width + 1, height + 1, width + 1]; // Weight of each point
// Generate chunk
PopulateTerrainMap();
CreateMeshData();
}
void PopulateTerrainMap(){
...
}
void CreateMeshData(){
ClearMeshData();
vertices = new List<Vector3>();
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
for (int z = 0; z < width; z++) {
Debug.Log(x + ", " + y + ", " + z + ", begin");
Vector3Int position = new Vector3Int(x, y, z);
// Set up memory pointers
NativeList<Vector3> marchVerts = new NativeList<Vector3>(Allocator.TempJob);
NativeList<int> marchTris = new NativeList<int>(Allocator.TempJob);
NativeList<float> mapSample = new NativeList<float>(Allocator.TempJob);
// Split marchcube into jobs by cube
instanceMarchCube = new MarchCubeJob(){
position = position,
marchVerts = marchVerts,
marchTris = marchTris,
mapSample = terrainMap
};
// Run job for each cube in a chunk
instanceJobHandle = instanceMarchCube.Schedule();
instanceJobHandle.Complete();
// Copy data from job to mesh data
//instanceMarchCube.marchVerts.CopyTo(vertices);
// Dispose of memory pointers
marchVerts.Dispose();
marchTris.Dispose();
mapSample.Dispose();
Debug.Log(x + ", " + y + ", " + z + ", end");
}
}
}
BuildMesh();
}
public void PlaceTerrain (Vector3 pos, int radius, float speed){
...
CreateMeshData();
}
public void RemoveTerrain (Vector3 pos, int radius, float speed){
...
CreateMeshData();
}
void ClearMeshData(){
vertices.Clear();
triangles.Clear();
}
void BuildMesh(){
Mesh mesh = new Mesh();
mesh.vertices = vertices.ToArray();
mesh.triangles = triangles.ToArray();
mesh.RecalculateNormals();
meshFilter.mesh = mesh;
meshCollider.sharedMesh = mesh;
}
private void OnDestroy(){
marchVerts.Dispose();
marchTris.Dispose();
}
}
// Build a cube as a job
[BurstCompile]
public struct MarchCubeJob: IJob{
static float terrainSurface { get { return Terrain_Data.terrainSurface;}}
public Vector3Int position;
public NativeList<Vector3> marchVerts;
public NativeList<int> marchTris;
public float[,,] mapSample;
public void Execute(){
//Sample terrain values at each corner of cube
float[] cube = new float;
for (int i = 0; i < 8; i++){
cube[i] = SampleTerrain(position + Terrain_Data.CornerTable[i]);
}
int configIndex = GetCubeConfiguration(cube);
// If done (-1 means there are no more vertices)
if (configIndex == 0 || configIndex == 255){
return;
}
int edgeIndex = 0;
for (int i = 0; i < 5; i++){ // Triangles
for (int p = 0; p < 3; p++){ // Tri Vertices
int indice = Terrain_Data.TriangleTable[configIndex, edgeIndex];
if (indice == -1){
return;
}
// Get 2 points of edge
Vector3 vert1 = position + Terrain_Data.CornerTable[Terrain_Data.EdgeIndexes[indice, 0]];
Vector3 vert2 = position + Terrain_Data.CornerTable[Terrain_Data.EdgeIndexes[indice, 1]];
Vector3 vertPosition;
// Smooth terrain
// Sample terrain values at either end of current edge
float vert1Sample = cube[Terrain_Data.EdgeIndexes[indice, 0]];
float vert2Sample = cube[Terrain_Data.EdgeIndexes[indice, 1]];
// Calculate difference between terrain values
float difference = vert2Sample - vert1Sample;
if (difference == 0){
difference = terrainSurface;
}
else{
difference = (terrainSurface - vert1Sample) / difference;
}
vertPosition = vert1 + ((vert2 - vert1) * difference);
edgeIndex++;
}
}
}
static int GetCubeConfiguration(float[] cube){
int configurationIndex = 0;
for (int i = 0; i < 8; i++){
if (cube[i] > terrainSurface){
configurationIndex |= 1 << i;
}
}
return configurationIndex;
}
public float SampleTerrain(Vector3Int point){
return mapSample[point.x, point.y, point.z];
}
}```

### How to remove a vector from a vector 3 list in c# for unity

```I am struggling to remove vectors from a vector three list. I am trying to spawn a box at a position randomly selected from a list. I then need to remove the item from the list so that two boxes don't spawn in the same place. I have tried RemoveAt and Remove(used vector) but non have worked. Any help would be much appreciated.
void Start()
{
Vector3[] Pos = new Vector3[amount_of_pallet];
for (int i =0; i<=amount_of_pallet-1; i++)
{
Pos[i] = new Vector3(startX, 0.5f, 0f);
startX = startX + pallet.transform.localScale.x;
Debug.Log("pos of box = "+Pos[i]);
Debug.Log("x = "+startX);
}
for (int i=0; i < Pos.Length; i++)
{
Random random = new Random();
int posi = Random.Range(0, Pos.Length);
Vector3 val = Pos[posi];
Instantiate(spawnee, Pos[posi],`Quaternion.identity);`
Pos.RemoveAt(posi);
```
```Use list and remove and get func from list
void Start()
{
List<Vector3> contList = new List<Vector3>();
for (int i = 0; i < amount_of_pallet; i++)
{
startX = startX + pallet.transform.localScale.x;
}
Random random = new Random();
for (int i = 0; i < contList.Count; i++
{
var index = Random.Range(0, contList.Count);
Vector3 position = RemoveAndGet(contList, index);
Instantiate(spawnee, position, Quaternion.identity);
}
}
public T RemoveAndGet<T>(IList<T> list, int index)
{
lock(list)
{
T value = list[index];
list.RemoveAt(index);
return value;
}
}
Another solution is shuffle your list and just iterate over it. Something like this:
void Start()
{
List<Vector3> contList = new List<Vector3>();
for (int i = 0; i < amount_of_pallet; i++)
{
startX = startX + pallet.transform.localScale.x;
}
Shuffle(contList);
foreach (Vector3 position in contList)
{
Instantiate(spawnee, position, Quaternion.identity);
}
contList.Clear();
}
private System.Random rng = new System.Random();
public void Shuffle<T>(IList<T> list)
{
int n = list.Count;
while (n > 1) {
n--;
int k = rng.Next(n + 1);
T value = list[k];
list[k] = list[n];
list[n] = value;
}
}```

### Replacing hexagons with destroyed hexagons

```I want to replace the destroyed hexagons with other standing hexagons. Existing hexagons should fall from the top. For example if I destroy (0,2) positioned hexagon in the picture below, the top left hexagon which position of that hexagon is (0,0) should be moved to (0,2) position and i should create a new hexagon and put it on (0,0) which is empty now because we moved the hexagon on (0,0) to (0,2) earlier.
I have a two dimensional array that stores all the references of hexagons with an index of the hexagon's coordinate (x,y).
--IMPORTANT--
Moving the objects is not important. The important part is we have to know which hexagon will be replaced with another. We have to tell the ARRAY that we changed those hexagons and the hexagons that were just moved or created should have exactly one reference in the index of their new (x,y) positions.
VIDEO FOR BETTER EXPLAINING WHAT I WANT TO DO
Any ideas or help would be appreciated!
Hexagon Coordinate system (ignore red arrows)
public void CreateGrid(int gridWidth, int gridHeight)
{
for (int y = 0; y < gridHeight; y++)
{
for (int x = 0; x < gridWidth; x++)
{
GameObject Hexagon = Instantiate(HexagonPre, Vector2.zero, Quaternion.identity, HexGrid);
int RandColor = Random.Range(0, 5);
if (RandColor == 0)
{
Hexagon.GetComponent<SpriteRenderer>().color = Color.blue;
}
else if (RandColor == 1)
{
Hexagon.GetComponent<SpriteRenderer>().color = Color.red;
}
else if (RandColor == 2)
{
Hexagon.GetComponent<SpriteRenderer>().color = Color.green;
}
else if (RandColor == 3)
{
Hexagon.GetComponent<SpriteRenderer>().color = Color.yellow;
}
else if (RandColor == 4)
{
Hexagon.GetComponent<SpriteRenderer>().color = Color.cyan;
}
Vector2 gridPos = new Vector2(x, y);
Hexagon.transform.position = CalcWorldPos(gridPos);
Hexagon.GetComponent<HexCoordinates>().Coordinates = new Vector2Int(x, y);
Hexagon.transform.name = "X: " + x + " | Y: " + y;
}
}
}
Code for destroying hexagons
if (MatchedColors == 2)
{
if(!HexToBeDestroyed.Contains(Hexagons[x, y].gameObject))
if (!HexToBeDestroyed.Contains(Hexagons[x - 1, y].gameObject))
if (!HexToBeDestroyed.Contains(Hexagons[x - 1, y - 1].gameObject))
HexToBeDestroyed.Add(Hexagons[x - 1, y - 1].gameObject);
}
MatchedColors = 0;
}
}
}
}
foreach (GameObject G in HexToBeDestroyed)
{
if (G != null)
{
Destroy(G.gameObject);
}
}
```
```Explanation for code is in comments:
void HexagonFall(GameObject[,] hexArray)
{
// Handle fall for base columns and for offset columns
for (int offset = 0 ; offset < 2 ; offset++)
{
// Handle fall for each column at current offset
for (int x = 0 ; x < hexArray.GetLength(0) ; x++)
{
int bottomYIndex = hexArray.GetLength(1) - offset - 1;
// List of indices of where each hexagon in that column will come from.
// We will fill from bottom to top.
List<Vector2Int> sourceIndices = new List<Vector2Int>();
for (int y = bottomYIndex ; y >= 0 ; y-=2)
{
// HexExists returns true if the hex isn't empty.
// Something along the lines of ` return input!=null; `
// depending on what "empty" hexes look like in the array
if (HexExists(hexArray[x,y]))
{
}
}
// We have a list of where to get each bottom hexes from, now do the move/create
for (int y = bottomYIndex; y >= 0 ; y-=2)
{
if (sourceIndices.Count > 0)
{
// If we have any available hexes in column,
// use the bottommost one (at index 0)
hexArray[x,y] = hexArray[sourceIndices.x, sourceIndices.y];
// We have now found a home for hex previously at sourceIndices.
// Remove that index from list so hex will stay put.
sourceIndices.RemoveAt(0);
}
else
{
// Otherwise, we need to generate a new hex
hexArray[x,y] = MakeNewHexAt(new Vector2Int(x,y));
}
// Tell the hex about its new home
hexArray[x,y].GetComponent<HexCoordinates>().Coordinates = new Vector2Int(x, y);
hexArray[x,y].transform.name = "X: " + x + " | Y: " + y;
}
}
}
}
In your hex destroying code, I would change HexToBeDestroyed to be a List of Vector2Int so you can set the array references to null immediately when you Destroy the gameobject:
List<Vector2Int> HexToBeDestroyed = new List<Vector2Int>();
// ...
if (MatchedColors == 2)
{
if(!HexToBeDestroyed.Contains(new Vector2Int(x, y))
if (!HexToBeDestroyed.Contains(new Vector2Int(x - 1, y))
if (!HexToBeDestroyed.Contains(new Vector2Int(x - 1, y - 1)))
HexToBeDestroyed.Add(new Vector2Int(x - 1, y - 1));
}
// ...
foreach (Vector2Int V in HexToBeDestroyed)
{
if (Hexagons[V.x,V.y] != null)
{
Destroy(Hexagons[V.x,V.y]);
Hexagons[V.x,V.y] = null;
}
}
As far as moving the hexes goes, I would add this in the Update of HexCoordinates:
float fallSpeed = 0.5f;
Vector2 goalWorldPosition = GS.CalcWorldPos(Coordinates);
transform.position = Vector2.MoveTowards(transform.position, goalWorldPosition, fallSpeed * Time.deltaTime);```

### Map possible paths for amount of moves C#

```I am re-creating the game of cluedo and I want to map the possible paths that the player can move after dice roll.
I have mapped the grid by drawing pictureboxes and naming them to their mapped location.
Here is my code so far for the possible paths:
int Roll;
private void RollDice()
{
ResetTiles();
JimRandom Random = new JimRandom();
//Roll DIce 1
int dice1 = Random.Next(1, 7);
//Roll DIce 2
int dice2 = Random.Next(1, 7);
Roll = dice1 + dice2;
//Set Dice images
pbDice1.BackgroundImage = Roller[dice1 - 1].Picture;
pbDice2.BackgroundImage = Roller[dice2 - 1].Picture;
btnRoll.Enabled = false;
Test(Roll);
//Show available moves
Control[] lCurrent = PnlBoard.Controls.Find("pnl" + CurrentPlauer, true);
Panel Current = null;
System.Drawing.Point CurrentLoc = new System.Drawing.Point(0, 0);
foreach (Control c in lCurrent)
{
Current = c as Panel;
CurrentLoc = new System.Drawing.Point(c.Location.X, c.Location.Y);
}
//Dynamic map
List<string> possiblities = new List<string>();
int currentRow = CurrentLoc.Y / tileWidth;
int currentCol = CurrentLoc.X / tileHeight;
//Find all possible start blocks
string down = String.Format("Col={0:00}-Row={1:00}", currentCol, currentRow + 1);
string up = String.Format("Col={0:00}-Row={1:00}", currentCol, currentRow - 1);
string left = String.Format("Col={0:00}-Row={1:00}", currentCol - 1, currentRow);
string right = String.Format("Col={0:00}-Row={1:00}", currentCol + 1, currentRow);
List<string> startBlocks = new List<string>();
//See if down is available
Control[] LPossible = PnlBoard.Controls.Find(down, true);
if (LPossible.Length > 0)
{
}
//See if Up is available
LPossible = PnlBoard.Controls.Find(up, true);
if (LPossible.Length > 0)
{
}
//See if left is available
LPossible = PnlBoard.Controls.Find(left, true);
if (LPossible.Length > 0)
{
}
//See if right is available
LPossible = PnlBoard.Controls.Find(right, true);
if (LPossible.Length > 0)
{
}
//possiblilities 1
foreach (string s in startBlocks)
{
Control[] lStarBlock = PnlBoard.Controls.Find(s, true);
PictureBox startBlock = lStarBlock as PictureBox;
int sRow = startBlock.Location.Y / tileWidth;
int sCol = startBlock.Location.X / tileHeight;
//Rows
for (int row = sRow; row < sRow + Roll; row++)
{
//Columns
for (int col = sCol; col < sCol + Roll; col++)
{
}
}
}
//Show possible moves
foreach (string p in possiblities)
{
LPossible = PnlBoard.Controls.Find(p, true);
if (LPossible.Length > 0)
{
PictureBox active = LPossible as PictureBox;
active.Image = Cluedo.Properties.Resources.TileActive;
Application.DoEvents();
}
//else
//{
// break;
//}
}
}
```
```There's a lot of things I would do different here. This is more of a Code Review post, but there's a solution to your problem at the end, and perhaps the rest can help you to improve the overall state of your code.
Randomness
You're creating a new random generator instance for every method call:
JimRandom Random = new JimRandom();
This often results in the same values being generated if the method is called in rapid succession. Perhaps that's why you're using a cryptographic RNG instead of a PRNG? A PRNG should be sufficient for a game like this, as long as you reuse it.
Using the right types
You're determining the current player location with the following code:
//Show available moves
Control[] lCurrent = PnlBoard.Controls.Find("pnl" + CurrentPlauer, true);
Panel Current = null;
System.Drawing.Point CurrentLoc = new System.Drawing.Point(0, 0);
foreach (Control c in lCurrent)
{
Current = c as Panel;
CurrentLoc = new System.Drawing.Point(c.Location.X, c.Location.Y);
}
It looks like CurrentPlauer is a string. Creating a Player class that stores the name and current location of a player would make things much easier:
Point currentLocation = currentPlayer.Location;
Splitting game logic from UI code
You're checking for passable tiles by doing string lookups against controls:
string down = String.Format("Col={0:00}-Row={1:00}", currentCol, currentRow + 1);
// ...
Control[] LPossible = PnlBoard.Controls.Find(down, true);
if (LPossible.Length > 0)
{
}
Normally a 2D array is used for tile maps like these, possible encapsulated in a Tilemap or Map class. This makes working with tiles more natural, as you can work in tile coordinates directly instead of having to translate between UI and tile coordinates. It also breaks up the code more cleanly into a game-logic and a UI part (the code in your post is impossible to test without UI):
// TileMap class:
public bool IsPassable(int x, int y)
{
if (x < 0 || x >= Width || y < 0 || y >= Height)
return false;
return tiles[x][y] != Tile.Wall; // enum Tile { Wall, Ballroom, DiningRoom, Hall, ... }
}
// When called from your Board code:
if (map.IsPassable(currentLocation.X, currentLocation.Y + 1))
Reducing repetition
As for checking all direct neighboring tiles, there's no need to repeat the same code 4 times:
// Let's make a utility function:
public static IEnumerable<Point> GetNeighboringPositions(Point position)
{
yield return new Point(position.X - 1, position.Y);
yield return new Point(position.X, position.Y - 1);
yield return new Point(position.X + 1, position.Y);
yield return new Point(position.X, position.Y + 1);
}
// In the Board code:
foreach (Point neighboringPosition in GetNeighboringPositions(currentPosition))
{
if (map.IsPassable(neighboringPosition.X, neighboringPosition.Y))
}
Determining valid moves
Finally, we get to the code that determines which tiles the current player can move to:
//possiblilities 1
foreach (string s in startBlocks)
{
Control[] lStarBlock = PnlBoard.Controls.Find(s, true);
PictureBox startBlock = lStarBlock as PictureBox;
int sRow = startBlock.Location.Y / tileWidth;
int sCol = startBlock.Location.X / tileHeight;
//Rows
for (int row = sRow; row < sRow + Roll; row++)
{
//Columns
for (int col = sCol; col < sCol + Roll; col++)
{
}
}
}
What this does is checking a rectangular area, using a starting position as its top-left corner. It's doing so for up to 4 neighboring positions, so the rectangles will partially overlap each other. That's just not going to work. If the map didn't have any obstacles, something like this, combined with a Manhattan distance check, could work (if you don't forget to look to the left and upwards too). Or better, some fancy looping that checks a diamond-shaped area.
However, you've got walls to deal with, so you'll need a different approach. The player's current position is at distance 0. Its direct neighbors are at distance 1. Their neighbors are at distance 2 - except those tiles that are at a lower distance (the tiles that have already been covered). Any neighbours of tiles at distance 2 are either at distance 3, or have already been covered. Of course, wall tiles must be skipped.
So you need to keep track of what tiles have already been covered and what neighboring tiles you still need to check, until you run out of movement points. Let's wrap that up into a reusable method:
public List<Point> GetReachableTiles(Point currentPosition, int maxDistance)
{
List<Point> coveredTiles = new List<Point> { currentPosition };
List<Point> boundaryTiles = new List<Point> { currentPosition };
for (int distance = 0; distance < maxDistance; distance++)
{
List<Point> nextBoundaryTiles = new List<Point>();
foreach (Point position in boundaryTiles)
{
foreach (Point pos in GetNeighboringPositions(position))
{
// You may also want to check against other player positions, if players can block each other:
if (!coveredTiles.Contains(pos) && !boundaryTiles.Contains(pos) && map.IsPassable(pos.X, pos.Y))
{
// We found a passable tile:
// And we want to check its neighbors in the next 'distance' iteration, too: