[PlayerStage-Gazebo] Problem getting the Z value for the robot.. (DEM)

[Rasko P. <rpj...@gm...>]

Hi Nate and everybody,

I am using libgazebo to control the robot in the world that is DEM (its
not flat! created by gzbuilder )

this is part of my .c code that is supposed to get the coordinates of the
robot:

   printf("%0.3f %0.3f %0.3f\n",
           position->data->pos[0], position->data->pos[1],
           position->data->pos[2]);

So when I run wxgazebo and my code I can see that my robot is moving on
the terrain and X and Y coordinates are fine, but the Z coordinate is
always 0.000

-3.594 5.788 0.000
-3.603 5.752 0.000
-3.603 5.752 0.000
-3.611 5.719 0.000
-3.611 5.719 0.000
-3.618 5.685 0.000
-3.618 5.685 0.000

I am not sure if its important but the model of my robot is Pioneer2DX.
So what I am doing wrong?

Thank you,

Rasko