ZBuffer:

Code:
g_pd3dDevice.SetRenderState(D3DRS_ZENABLE, iTrue);
Projection matrix:

Code:
D3DXMatrixPerspectiveFovLH(matProj, D3DX_PI/4, 1.0, 1.0, 200.0);
g_pd3dDevice.SetTransform(D3DTS_PROJECTION, matProj);
The map is 64*64. 200 is more than enough.

Any clue? :?