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webjeff

Frustum Problem (Near and Far)

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Hello, I am having trouble with my View Frustum clipping. I decided to draw my frustum I am clipping against, turns out my clipping is working properly, its the frustum I am generating is different from what I expected. The near plane seems to be correct, because its where the camera is at. The far plane though, seems to be at 0. So, if my camera is at 150.0f, my near is 150.0f, my far is 0.0f. Now, in my projection, I set my far to be 1000.0f. Shouldn't my far clipping plane be at -850.0f? (I'm using DirectX) Here's how I build my frustum:
    Matrix16f Vp = GlGetViewMtx() * GlGetProjMtx();

    // Left plane 
    m_Frustum[0].N._x = Vp._14 + Vp._11;
    m_Frustum[0].N._y = Vp._24 + Vp._21;
    m_Frustum[0].N._z = Vp._34 + Vp._31;
    m_Frustum[0].D = Vp._44 + Vp._41;

    // Right plane 

    m_Frustum[1].N._x = Vp._14 - Vp._11;
    m_Frustum[1].N._y = Vp._24 - Vp._21;
    m_Frustum[1].N._z = Vp._34 - Vp._31;
    m_Frustum[1].D = Vp._44 - Vp._41;

    // Top plane 

    m_Frustum[2].N._x = Vp._14 - Vp._12;
    m_Frustum[2].N._y = Vp._24 - Vp._22;
    m_Frustum[2].N._z = Vp._34 - Vp._32;
    m_Frustum[2].D = Vp._44 - Vp._42;

    // Bottom plane 

    m_Frustum[3].N._x = Vp._14 + Vp._12;
    m_Frustum[3].N._y = Vp._24 + Vp._22;
    m_Frustum[3].N._z = Vp._34 + Vp._32;
    m_Frustum[3].D = Vp._44 + Vp._42;

    // Near plane 

    m_Frustum[4].N._x = Vp._13;
    m_Frustum[4].N._y = Vp._23;
    m_Frustum[4].N._z = Vp._33;
    m_Frustum[4].D = Vp._43;

    // Far plane 

    m_Frustum[5].N._x = Vp._14 - Vp._13;
    m_Frustum[5].N._y = Vp._24 - Vp._23;
    m_Frustum[5].N._z = Vp._34 - Vp._33;
    m_Frustum[5].D = Vp._44 - Vp._43;

    
    
    // Normalize
    for (int i = 0; i < 6; i++)
        PlaneNormalize(m_Frustum);

Any ideas? Thanks Jeff.

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