max exporting problem?

hi there, my problem is simple.. i was exporting from 3dsmax a scene and it used to work just fine.. i got the code again and tried to use it for an engine the problem is that it doesnt display the scene correctly! i have a mesh which is made of 3 objects.. a tree! we have the trunk and then the other child trunks, the problem is that when i loop thru every object to draw them all it displays the objects incorrectly! doesnt look anything like the original object! what i do is simple looping: for every object for every objects''s face glBegin(GL_TRIANGLES) for the 3 vertices in each triangle { glColor(r, g, b) // swap y and z and negate y ... glVertex3f(x, z, -y) } glEnd() well this is the render loop i do.. i dunno whats wrong.. shouldnt exporting from max directly into an engine work just fine? in world coordinates? maybe its camera coordinates since i draw it after glLookAt? any ideas? thanks in advance