Direct 3D 7.0 Immediate Mode when i push a 3d mesh far away while animating(or even translating it on the timekey) from the viewport camera the polygons begin to disappear.this makes it look real crappy this doesen''t happen in case of microsoft''s meshes(heli.x). even two boxes close to each other reveal this artifact. should i use the w-buffer?? Please give me the reason to this problem and how do i fix it????