The code below to rotate the earth and moon is still not working The moon is spending about 90% of the time on the outside of the earth. Here is my actual adjusted code: I was wondering if it was valid to simply negate a rotation amount as below, also I am assuming the overloaded * can handle multiple matrix multiplications. fEarthRotSun = m_fRotationCurrent/3; fEarthRotSelf = m_fRotationCurrent; fMoonRotSelf = m_fRotationCurrent/2; fMoonRotEarth = m_fRotationCurrent/2; D3DUtil_SetTranslateMatrix(T2, 0,0,3.0f);//earth orbit dist. D3DUtil_SetTranslateMatrix(T1, 0,0,1.5f);//moon orbit dist. D3DUtil_SetRotateYMatrix(R1, fMoonRotSelf); D3DUtil_SetRotateYMatrix(R2, fMoonRotEarth); D3DUtil_SetRotateYMatrix(R5,-fEarthRotSun); D3DUtil_SetRotateYMatrix(R4, fEarthRotSelf); D3DUtil_SetRotateYMatrix(R3, fEarthRotSun); World = R1 * T1 * R2 * R5 * T2 * R3; m_pd3dDevice->SetTransform(...,&World) // Render moon m_pd3dDevice->DrawPrimitive(...) // The earth''s world matrix World = R4 * T2 * R3; m_pd3dDevice->SetTransform(...,&World); // Render earth m_pd3dDevice->DrawPrimitive(...);

could I email the code to you or do you want me to post it here?