Opengl Matrix Translation Issues having trouble with my 3D game.

hey

i'm making a game, and just went to implement collision detection when i found that it would be incredibly difficult because of a shortcut i added to work around a problem. now i'm going back to fix that problem, but i'm running out of ideas.

i'm trying to do this... (in c++)

xPos = (whatever); //the x and z coordinates of the object.zPos = (whatever);rotation = (whatever); //the rotation of the object in degrees.glPushMatrix();    glTranslatef(xPos, 0, yPos);    glRotatef(rotation);    renderObject();glPopMatrix();

and draw an object at xPos,0,yPos with a rotation of 'rotation'.

instead, the object appears at xPos, 0, -yPos. the problem can be fixed by putting doing this for the translation:

glTranslatef(xPos, 0, yPos);

and until now this is what i was doing, but it makes things like collision detection and camera work much more complicated later on.

does anyone have any ideas on why this would be occuring and/or how to fix it?

thanks, muchly appreciated.

ok sorry that post was riddled with problems. zPos (in the second line of the first block of code) should be yPos, and the second block of code should read

glTranslatef(xPos, 0, -yPos);

ok thanks sorry about that.