Hello there. I hope you can help me out. I had a thread not too long ago, because I needed the code for extracting planes for the frustum culling. I finally got it working. Thanks to those who helped.
Now I need to know whether or not a sphere is in the viewing frustum (inside the six planes). This is what I have, and I got it somewhere on the web:
float fDistance = 0.0f; // Distance from sphere to plane
float fTotal = 0.0f;
// Check sphere against each side of the frustum
for (int i = 0; i < MAX_SIDES; i++)
{
// Calculate distance from sphere to plane
fDistance = ((m_Frustum[i].a * pvPos->x) + (m_Frustum[i].b * pvPos->y) + (m_Frustum[i].c * pvPos->z) + (m_Frustum[i].d));
fTotal = (D3DXVec3Dot(new D3DXVECTOR3(m_Frustum[i].a, m_Frustum[i].b, m_Frustum[i].c), pvPos) + fDistance);
if (fTotal < (-radius)) // Check distance
return false; // Not inside ''i'' side of the frustum
}
That may be wrong, but I am not sure. I have it to where it checks a sphere, and displays it in the title bar. It always says "IsSphereVisible(...)" returns false, unless I look off in the distance, away from my terrain. Here''s how I calculate the frustum, in case you need to know:
D3DXMatrixMultiply(&matClip, matView, matProj); // Get the clipping plane information
D3DXMatrixInverse(&matClip, NULL, &matClip);
m_vecFrustum[0] = D3DXVECTOR3(-1.0f, -1.0f, 0.0f); // xyz
m_vecFrustum[1] = D3DXVECTOR3( 1.0f, -1.0f, 0.0f); // Xyz
m_vecFrustum[2] = D3DXVECTOR3(-1.0f, 1.0f, 0.0f); // Xyz
m_vecFrustum[3] = D3DXVECTOR3( 1.0f, 1.0f, 0.0f); // Xyz
m_vecFrustum[4] = D3DXVECTOR3(-1.0f, -1.0f, 1.0f); // XyZ
m_vecFrustum[5] = D3DXVECTOR3( 1.0f, -1.0f, 1.0f); // XyZ
m_vecFrustum[6] = D3DXVECTOR3(-1.0f, 1.0f, 1.0f); // Xyz
m_vecFrustum[7] = D3DXVECTOR3( 1.0f, 1.0f, 1.0f); // Xyz
for (int i = 0; i < 8; i++)
D3DXVec3TransformCoord(&m_vecFrustum[i], &m_vecFrustum[i], &matClip);
// Create the frustum planes from the frustum vector
D3DXPlaneFromPoints(&m_Frustum[0], &m_vecFrustum[0], &m_vecFrustum[1], &m_vecFrustum[2]);
D3DXPlaneFromPoints(&m_Frustum[1], &m_vecFrustum[6], &m_vecFrustum[7], &m_vecFrustum[5]);
D3DXPlaneFromPoints(&m_Frustum[2], &m_vecFrustum[2], &m_vecFrustum[6], &m_vecFrustum[4]);
D3DXPlaneFromPoints(&m_Frustum[3], &m_vecFrustum[7], &m_vecFrustum[3], &m_vecFrustum[5]);
D3DXPlaneFromPoints(&m_Frustum[4], &m_vecFrustum[2], &m_vecFrustum[3], &m_vecFrustum[6]);
D3DXPlaneFromPoints(&m_Frustum[5], &m_vecFrustum[1], &m_vecFrustum[0], &m_vecFrustum[4]);
for (i = 0; i < 6; i++)
D3DXPlaneTransform(&m_Frustum[i], &m_Frustum[i], &matClip);
Do I need to normalize the planes (D3DXPLANE m_Frustum[6])?
Thanks in advance.
I'll have a link to the TriFaze website as soon as possible. It's still currently being designed, by myself of course! =) I'll update the URL and my signature as soon as possible.Feel free to send me a message on Yahoo! or AOL IM™. =)
