cocos2d for iPhone

A fast, easy to use, free, and community supported 2D game engine

1. 

   artakus
   Member

   I use TMX Map and wonder how do I retrieve its coordinate when I "click on it"? I've search through this forum and didn't find the solution. for example i touch on the map (Yes Map. Not iphone screen) which location is 0,0. and it return 0,0.

   [/CODE]

   -(id)init
   {
   if((self=[super init]))
   {
   TMXTiledMap *map = [TMXTiledMap tiledMapWithTMXFile:@"level1.tmx"];
   [self addChild:map z:0 tag:tagMap];
   }
   }

   -(BOOL)ccTouchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
   {
   CocosNode *map=[self getChildByTag:kTagTilemap];

   //HOW TO RETRIEVE ITS VALUE HERE?

   }

   [/CODE]

   Posted 2 years ago #
2. 

   artakus
   Member

   It seem this thing doesn't include in documentation and I wish i could see its example. :(

   Posted 2 years ago #
3. 

   LongJohnnyE
   Member

   You might want to try something along these lines. I'm working on a game using TMX Map and was dealing with this yesterday.I haven't really had the chance to make sure it works, but it seemed to be working for my game.

   I created a subclass of TMXTiledMap and added a few methods, with this one included.

   - (CGPoint)coordinatesAtPosition:(CGPoint)point {
   	return ccp((int)(point.x / (self.mapSize.width)), (int)(self.mapSize.height - point.y / (self.mapSize.height)));
   }

   Edit: added casting to int.

   Posted 2 years ago #
4. 

   artakus
   Member

   @LongJohnnyE, thanks for your reply

   so let say my map height=10, and width = 15 then by using your method,

   - (BOOL)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
   {
   UITouch *touch = [touches anyObject];
   if( touch )
   {
   CGPoint location = [touch locationInView: [touch view]];
   CGPoint convertedPoint = [[Director sharedDirector] convertCoordinate:location];

   ///////////////////////////Your formula///////////////////////////////
   CGPoint clickMap = ccp((int)(convertedPoint.x/(15)), (int)(10-convertedPoint.y/(10)));

   NSLog(@"Coordinate X: %f",t.x);
   NSLog(@"Coordinate Y: %f",t.y);

   }
   }

   Im not getting the correct ouput.

   AM I MISSING SOMETHING ??

   What is the point refer to? our touch position?

   Posted 2 years ago #
5. 

   LongJohnnyE
   Member

   Height and width should be the number of tiles in your map. 10x15 seems kinda small.

   Posted 2 years ago #
6. 

   Blue Ether
   Member

   10x15 fills the screen with 32-pixel size tiles. Why does that seem to small? I can see plenty of applications for a tile map the size of one screen.

   But you aren't tracing the converted values. So, is that what you mean is having the wrong values?

   Posted 2 years ago #
7. 

   LongJohnnyE
   Member

   Oh, gotcha. Yea that's not really small, I was just doing things different in my game (using 8x8 pixel tiles).

   I don't quite understand what you mean about tracing converted values.

   What my functions does is take an absolute point and return the grid coordinate in the tilemap it corresponds to. Note that for my function to work, the tilemap has to be located at 0,0 with no offset, etc...

   Since the point needs to be absolute, if you have 'scrolled' your tilemap at all, then you need to offset for that in your touch function.

   Posted 2 years ago #
8. 

   artakus
   Member

   I did implement your code posted above.

   ///////////////////////method to return tilemap coordinate///////////////

   -(CGPoint)coordinatesAtPosition:(CGPoint)point
   {

   return ccp((int)(point.x/(15)), (int)(10-point.y/(10)));
   }

   ///////////////////////END OF method to return tilemap coordinate///////////////

   ///////////////////////touch event//////////////////

   - (BOOL)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
   {
   UITouch *touch = [touches anyObject];
   CGPoint location = [touch locationInView: [touch view]];
   CGPoint convertedPoint = [[Director sharedDirector] convertCoordinate:location];

   CGPoint locationClicked = [self coordinatesAtPosition:ccp((int)convertedPoint.x,(int)convertedPoint.y)];
   NSLog(@"CGPointX %.f",locationClicked.x);
   NSLog(@"CGPointY %.f", locationClicked.y);
   }

   ///////////////////////END OF touch event//////////////////

   The output are weird:

   when I touch at TileMap (0,0) - it will return :

   CGPointX: 0
   CGPointY: -21

   when touch at Tilemap(0,1) - it will return:

   CGPointX: 0
   CGPointY: -16 //sometime it return -17, -16, -15 same as others output. So from here i can see that the code doesn't return a tile coordinate with specific tile grid (one tile touch in one box). I can touch anywhere inside the box and get the different output.

   Is there any mistake I've made? How to return it same as what we click on the map :-(

   Posted 2 years ago #
9. 

   LongJohnnyE
   Member

   Print out the coordinates of the touch before you convert to tile coordinates, to make sure they are correct.

   To be honest, this problem is pretty simple to solve and I'm sure you can get it if you play around with the code a little. The only tricky thing is that you have to remember that coordinate (0,0) for the TMXTileMap is at the top-left most tile, which is why you have to treat it slightly differently.

   Posted 2 years ago #
10. 

    artakus
    Member

    1) I have printed out the coordinate before touch and yes they are correct. (Test both variable CGPoint location & CGPoint convertedPoint

    2) I have converted The point ccp coordinate to tile map base coordinate (Test both variable CGPoint location & CGPoint convertedPoint):

    - (BOOL)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
    {
    UITouch *touch = [touches anyObject];
    CGPoint location = [touch locationInView: [touch view]];
    CGPoint convertedPoint = [[Director sharedDirector] convertCoordinate:location];

    float newTileX = floor(convertedPoint.x/32);
    float newTileY = floor(convertedPoint.y/23);

    CGPoint locationClicked = [self coordinatesAtPosition:ccp((int)newTileX,(int)newTileY)];

    NSLog(@"CGPointX %f",locationClicked.x);
    NSLog(@"CGPointY %f", locationClicked.y);

    }

    Not success.

    Do you mean I have to convert My output? I don't get this.

    Posted 2 years ago #
11. 

    chrisco
    Member

    Hi Artakus - this was mentioned before in your other thread about this problem, and again here:

    "The only tricky thing is that you have to remember that coordinate (0,0) for the TMXTileMap is at the top-left most tile, which is why you have to treat it slightly differently."

    The coordinates returned by the touch are based on bottom left, but TMX map tiles start from top-left so this won't work. If your map fills the screen with 32px x 32px tiles, and you're clicking on the bottom-left tile of your map, you are essentially clicking on tile 0,9. It seems to me that you are expecting tile 0,0 to be returned, which it won't.

    Posted 2 years ago #
12. 

    LongJohnnyE
    Member

    Update! My previous code was retarded and only worked for me because I happened to be using a map where the mapSize and tileSize were the right ratio.

    Use this code to find the coordinates of a tile in the map based off a point based on pixels:

    return ccp((int)(point.x / self.tileSize.width), (int)(self.mapSize.height - (point.y / self.tileSize.height)));

    It actually works, unlike the crap I posted above. Sorry about that!

    Posted 2 years ago #
13. 

    artakus
    Member

    Hey really sorry for the late reply.

    @chriso, I know how to convert the TMXTileMap from your idea. Thanks you really help me. but this time i have problem how to get each tile coordinate when I click on the map

    @LongJohnnyE,

    I have One Map with Width = 18, height = 12
    I got the output by changing this line:

    CGPoint locationClicked = [self coordinatesAtPosition:ccp((int)convertedPoint.x,(int)convertedPoint.y)];

    To:

    CGPoint locationClicked = [self coordinatesAtPosition:ccp((int)convertedPoint.x/2,(int)convertedPoint.y/2)];

    -----------------------------

    I still not get the map coordinate if I drag it to the right / left then when I click at the different map location, it still show the same coordinate as fix iPhone screen coordinate.

    Here is what I want:
    When I click on a map let say at location Tile (8,9) Then it will return (8,9), So then I move my map to different location then I click again at the same location (8,9). I think it should not return the same coordinate. I hope you could understand my problem. How do I solve this thing.. :-(

    Posted 2 years ago #
14. 

    artakus
    Member

    anyone? Theres no way we could retrieve map coordinate in TMXTileMap??

    Posted 2 years ago #
15. 

    LongJohnnyE
    Member

    I posted some more details and code about how I got my scrolling game working with tileMap at http://johnehartzog.com/2009/10/2d-scrolling-game-with-cocos2d-tilemap-with-zoom/.

    Posted 2 years ago #

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