Objects on a tilemap

[AthenaOfDelphi]

The objects that I had that were bigger than a single tile were broken up into multiple tiles. By doing this I was able to create the illusion of depth by drawing them on different layers relative to the player so the 'front' were rendered behind the player while the 'back' was rendered in front of the player.

But, back to your question... how could this work if the objects are bigger than a tile? Good question

I'm not sure and it's not a solution I would pursue personally because of the overheads involved.

[User137]

Your original solution was almost perfect, but you are right, on larger maps it would get lower performance. Thus you can divide your map into chunks.

const CHUNKSIZE = 32;

TChunk = class
public
  posX, posY: integer;
  Tiles: array[0..CHUNKSIZE-1, 0..CHUNKSIZE] of TTile;
  Objects: array of TObject;
end;

TMap = class
public
  Chunks: array of array of TChunk;
  function GetTile(x, y: integer): TTile;
end;

function TMap.GetTile(x, y: integer): TTile;
var cx, cy: integer;
procedure
  cx:=x div CHUNKSIZE;
  cy:=y div CHUNKSIZE;
  result:=Chunks[cx, cy].Tiles[x-cx, y-cy]
end;

Or something along these lines... Of course you could do range checking in GetTile() to avoid critical errors on negative values or out of boundaries.

[Carver413]

if I were trying to do someting like this I would use an 8bit index map and use index 0 as a null. the background would be for normal size tiles while the forground would be for larger tiles. then I would add a clip frame that reperesents the view able portion of the map. now all you have to do is move the clipframe around within the map to change the view. on the forground the indexed position would be the top/left and all indexes underneath it would be 0's. your clip frame would have to be larger then the actual view so if a larger tile were half on it would still be displayed.