void RenderVertexForGL (const CVertex & v)
{
    glColor4f (v.m_Color.r, v.m_Color.g, v.m_Color.b, v.m_Color.a);
    glTexCoord2f (v.m_TexCoord.x, v.m_TexCoord.y);
    glNormal3f (v.m_Normal.x, v.m_Normal.y, v.m_Normal.z);
    glVertex3f (v.m_Position.x, v.m_Position.y, v.m_Position.z);
}

void CTerrain::Render ()
{
    // ...

    //  Render the terrain
    //  y
    for (int i = 0; i < size-1; i++)
    {
        glBegin (GL_TRIANGLE_STRIP);
        //glBegin (GL_LINES);
        //  x
        for (int ii = 0; ii < size; ii++)
        {
            const CVertex
                & v1 = vertices [size*i + ii],
                & v2 = vertices [size*(i+1) + ii];

            RenderVertexForGL (v1);
            RenderVertexForGL (v2);
        }
        glEnd ();
    }

    // ...
}