TMXTiledMap returns somehow translated object y coordinates, what's the catch?

cocos2d-x C++
#1

Hi!

I’m familiarizing myself with TMXTiledMap class. I made a couple of test objects (1x1 tile objects) for my .tmx:

 <objectgroup id="2" name="Objects">
  <object id="1" name="SpawnPoint" x="64" y="544" width="32" height="32"/>
  <object id="2" name="TestPoint1" gid="10" x="0" y="32" width="32" height="32"/>
  <object id="3" name="TestPoint2" gid="10" x="0" y="1600" width="32" height="32"/>
 </objectgroup>

Map is like this:

<map version="1.2" tiledversion="1.3.2" orientation="orthogonal" renderorder="right-down" compressionlevel="-1" width="50" height="50" tilewidth="32" tileheight="32" infinite="0" nextlayerid="3" nextobjectid="5">

Thus, map size in pixels is 1600x1600.

Returned y values for the three objects are:

  1. SpawnPoint y = 1024 (for 544)
  2. TestPoint1 y = 1536 (for 32)
  3. TestPoint2 y = -32 (for 1600)

It seems that y’s are somehow translated. But why is one even a negative number? What is the translation for? Can I configure it somehow?

#2

Advices:

  • Do not use .tmx files. Use an image that contains the tiles instead. Cocos doesn’t support .tsx files yet. You could have some problems.

  • The max map size that cocos supports, as I know, is 128x128 (tiles and px, width/height). Do not try to use bigger maps than this. If you need it, you should concatenate different maps. I’ve never did it but I know that this is possible.

Hope it helps.

#3

I use a single image that contains all tiles, and the size of the map is 50x50 tiles, each tile being 32x32 pixels. There is margin=1 and spacing=1, since all tiles are surrounded by 1px line.

I’m actually going throught this tutorial:

and trying to replicate it in cocos2d-x 4.0.

Still, I think the implementation of TiledMap must be very buggy, as one of the coordinates ended up being negative, which should never happen.

#4

I’ve have some oddness in the Creator version. But basically the Y is inverted. So the bottom most tile is 0 and y increases as you move up the screen.
Yours is offset by 32 it seems. So the “anchor” point is at 32 but since it is Y flipped it is at 1568. Hence going down to testPoint 2 puts you at -32 and then +32 is 1536. and then 1024 is 544. so newY = Y-1632

However such logic woks for me on windows, but fails on iOS.