You are an experienced programmer and have a problem with the engine, shaders, or advanced effects? Here you'll get answers. No questions about C++ programming or topics which are answered in the tutorials!
This is due to zbuffer limitations. Due to a limited bitwidth you get a limited accuracy which may impose these problems. There is a method for this provided in OpenGL (probably also in DX), but it's not available from within Irrlicht at the moment.
What do you want to do with the two planes?
One plane considering as ground and another one is floor. I'm using Directx. can u pls tell me the API of Direct3D. So that i ll try to solve the problem.. It is spoiling the look of my application..