   how to know a coordinate in a world scene
  hi.. i need some help to know what the coordinate of my object. eventually i have create two object from a data file and display it in a world scene.. when i detect the object, it has the same value but in the world scene it appears to be on different place (because of the glTranslatef)... so how can i get and use the coordinate of this object (both object)..help please..  
  I dont think you forgot to do that, but still...do you call loadIdentity() before placing your new object in the scene?If you dont do that, then your second translation is added to the first. That could explain the misplacement...  ;  i did use the glLoadIdentity().. i''m having problem because the value of the object is the same.. so when i''m trying my formula for collision detection, it detect that both object have the same value but still they don''t collide yet in the world scene. so when the collision function is called, it always return true value. that''s why i need to know how to get the actual coordinate for both the object to make a new collision checking function.. thanks ..  ;  right... Its not really clear to me.You have a reference to your objects, right?If you do, you can just write their coordinates on the screen to understand what s going on. In which case you need a font (which can be a bit too long if you havent done one already)The easier way in my opinion is to bind a key to a function that opens a file, then printf the coordinates of both objects. Its not as dynamic as printing it on the screen, but at least you ''ll get the values you want.You could dump the position at each frame as well as some other info from your collision function.Even better : run your program into the debugger.....  