10 replies to this topic

[Thekill473]

Hello everybody. currently for my rpg game I'm working on a map editor much like the ones from the rpg maker series. Ive been searching around and cant find any methods on how to implement a fill button. I guess it would have to use an expanding path finding algorithm, I know theres one out there I just cant remember the name. But has anybody got their two cents on it.

[Zoomulator]

You mean like a flood fill?

[Thekill473]

i knew i was missing something. Thanks a lot man for the link.

-Thekill

[Thekill473]

Well i found this algorithm and made it to work in my engine. there's just one problem. Whenever i use it it will fill the entire map because it seems to jump over tiles. and even once it's filled the entire map it just keeps going until it runs our of memory.
Ive debugged it and i cant seems to find why it keeps continuing even after its passed the maps width and height values.

private void FloodFill(Point q, Tile seed, Tile replacement)
		{
			int h = maps[clbLevels.SelectedIndex].YLevels[clbYLevels.SelectedIndex].Layers[clbLayers.SelectedIndex].Height;
			int w = maps[clbLevels.SelectedIndex].YLevels[clbYLevels.SelectedIndex].Layers[clbLayers.SelectedIndex].Width;
			if (q.Y < 0 || q.Y > h - 1 || q.X < 0 || q.X > w - 1)
				return;
			Stack<Point> stack = new Stack<Point>();
			stack.Push(q);
			while (stack.Count > 0)
			{
				Point p = stack.Pop();
				int x = p.X;
				int y = p.Y;
				if (y < 0 || y > h - 1 || x < 0 || x > w - 1)
					continue;
				Tile val = new Tile(maps[clbLevels.SelectedIndex].YLevels[clbYLevels.SelectedIndex].Layers[clbLayers.SelectedIndex].GetTile(x, y).TileIndex, maps[clbLevels.SelectedIndex].YLevels[clbYLevels.SelectedIndex].Layers[clbLayers.SelectedIndex].GetTile(x, y).TileSetIndex);
				if (val.TileIndex == seed.TileIndex && val.Tileset == val.Tileset)
				{
					maps[clbLevels.SelectedIndex].YLevels[clbYLevels.SelectedIndex].Layers[clbLayers.SelectedIndex].SetTile(x, y, replacement.TileIndex, replacement.Tileset, replacement.CollisionType);
					stack.Push(new Point(x + 1, y));
					stack.Push(new Point(x - 1, y));
					stack.Push(new Point(x, y + 1));
					stack.Push(new Point(x, y - 1));
				}
			}
		}

Thanks for reading

-Thekill

Edited by Thekill473, 01 July 2012 - 11:04 PM.

[RulerOfNothing]

The problem is not immediately obvious to me (I think it might have something to do with val.Tileset == val.Tileset), but I think you should probably put maps[clbLevels.SelectedIndex].YLevels[clbYLevels.SelectedIndex].Layers[clbLayers.SelectedIndex] into a temporary variable, seeing as it is quite an unwieldy expression.

Edited by RulerOfNothing, 02 July 2012 - 02:51 AM.

[Zoomulator]

Guessing that's C#?

I'm not at all familiar with that language, so I those 'new' statements are pretty confusing for a C++ programmer.. They wouldn't compile in the first place, and if they did they'd be a source for a memory leak!

But since that's probably not the case..

C# seems to have the same operator precedence, but I'd probably reinforce your intent here anyway. You're also using it twice. Make it a function!

bool OutOfBounds( Point p, int w, int h )
   {
   return
	 (p.Y < 0) ||
	 (p.Y > (h - 1)) ||
	 (p.X < 0) ||
	 (p.X > (w - 1));
   }

I don't think that would change much though...

On row 16, what is the purpose of the comma separating the new statement and the map access? I agree with RulerOfNothing.. some of those statements are just too big to make much sense out of.

Edited by Zoomulator, 02 July 2012 - 03:14 AM.

[azorac]

I think you are over complicating it? I use the following in my editor to fill entire maps with the same tile:
[source lang="csharp"] void fillMap(int mapWidth, int mapHight, int tileSet, int texture) { for (int x = 0; x < mapWidth; x++) { for (int y = 0; y < mapHight; y++) { map.tilesLayer0[x, y].tileSet = tileSet; map.tilesLayer0[x, y].texture = texture; } } }[/source]

Or am I misunderstanding what you are trying to do?

[Thekill473]

I got it working. Now it functions as it should. Thanks for all the help.

-thekill

[jbadams]

I got it working.

Could you share your solution for the benefit of anyone who has a similar problem in future?

[Sik_the_hedgehog]

I think you are over complicating it? I use the following in my editor to fill entire maps with the same tile:
[source lang="csharp"] void fillMap(int mapWidth, int mapHight, int tileSet, int texture) { for (int x = 0; x < mapWidth; x++) { for (int y = 0; y < mapHight; y++) { map.tilesLayer0[x, y].tileSet = tileSet; map.tilesLayer0[x, y].texture = texture; } } }[/source]

Or am I misunderstanding what you are trying to do?

That draws a filled rectangle, what he's doing is more akin to the flood fill tool (e.g. bucket) from painting programs. Although a filled rectangle is probably an useful thing to have in such an editor too.

[Thekill473]

Well I was being stupid and missed one of my checks.

if (val.TileIndex == seed.TileIndex && val.Tileset == val.Tileset)

Is meant to be

if (val.TileIndex == seed.TileIndex && val.Tileset == seed.Tileset)

And here is the original i found online.

private static void Floodfill(byte[,] vals, Point q, byte SEED_COLOR, byte COLOR)
{
    int h = vals.GetLength(0);
    int w = vals.GetLength(1);

    if (q.Y < 0 || q.Y > h - 1 || q.X < 0 || q.X > w - 1)
	    return;

    Stack<Point> stack = new Stack<Point>();
    stack.Push(q);
    while (stack.Count > 0)
    {
	    Point p = stack.Pop();
	    int x = p.X;
	    int y = p.Y;
	    if (y < 0 || y > h - 1 || x < 0 || x > w - 1)
			    continue;
	    byte val = vals[y, x];
	    if (val == SEED_COLOR)
	    {
			    vals[y, x] = COLOR;
			    stack.Push(new Point(x + 1, y));
			    stack.Push(new Point(x - 1, y));
			    stack.Push(new Point(x, y + 1));
			    stack.Push(new Point(x, y - 1));
	    }
    }
}

At
http://stackoverflow.com/questions/1257117/does-anyone-have-a-working-non-recursive-floodfill-algorithm-written-in-c

Hope this post helps anybody else in the future looking for a flood fill algorithm.