Using Tileset Image Properties in a Cocos2d TMXTiledMap - ios

Question

I'm working on an iOS game that uses a Cocos2d TMXTiledMap to read isometric maps produced in the Tiled Application.
In Tiled you can add properties to each image in a tileset (ie. the images displayed in the lower right corner of the screen)
It makes sense to me to use these properties to help determine whether or not this tile type is traversable by the game character.
For instance, if tile 3,5 is using an image of grass then land-based characters can walk there.
Conversely, if tile 4,8 is using an image of water then land-based characters cannot walk there.
I had hoped to accomplish this by creating a property on the grass and water tiles called terrain_type that would be 0 for land and 1 for water. Then (I had hoped) I could access tile 3,5 at runtime and somehow know that tile 3,5 used the grass image with the property of terrain_type=0
Now, I realize that there are other techniques available to accomplish the same thing (Object Layers come to mind) but this seems like the best way to go about it. Especially when you add multiple tile layers and you want to know that say tile 3,5 has both grass AND a wall on it.
My questions: Is this possible? And how would I go about it. Or, am I misunderstanding something about how Tiled and TMXTiledMap are supposed to work?
Much appreciated...

Answer 1

Amazing. I spent a lot of time trying to get this to work before I posted the question and, of course, I figured it out a few hours later. The key is to use the CCTMXMapInfo class.
Anyway, here's the solution since I think this could be useful to others:
In the Tiled application create a map that has a tile layer named
"bottom"
Add a property to each tile image in the section called
"Tilesets" (bottom right corner) by right clicking on each image and
selecting "Tile Properties"
Name the property "terrain_type" and set the value to whatever you like (e.g. terrain_type = 0 for land or terrain_type = 1 for water)
Use these images to paint your tilemap and save
Use this code to read the properties for a single tile at location 3,5:
//read the tile map
TMXTiledMap *tileMap = [CCTMXTiledMap tiledMapWithTMXFile:#"sample_map.tmx"];
//get the bottom layer from the tileMap
CCTMXLayer *bottomLayer = [tileMap layerNamed:#"bottom"];
//get CCTMXMapInfo object -- TMXTiledMap DOES NOT Contain the tile image properties
CCTMXMapInfo * mapInfo = [CCTMXMapInfo formatWithTMXFile: #"sample_map.tmx"];
//get tile id of the tile image used at this coordinate (3, 5) in this layer
int tileID = [bottomLayer tileGIDAt: ccp(3, 5)];
//get the properties for that tile image
NSDictionary *properties = [mapInfo.tileProperties objectForKey:[NSNumber numberWithInt:tileID] ];
//get the terrain_type property
NSString *terrainType = [properties objectForKey:#"terrain_type"];