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Can someone doing frustum culling in Direct3D 8/9 please give a little code?

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Hey there. I''ve been trying to get this working for a while. I posted on this subject once, but I didn''t get the correct response. A few people responded, and they offered some help, but it wasn''t what I needed. Anyhow, I am trying to do frustum culling in Direct3D 8. I do not perform any transformations on my world matrix (D3DTS_WORLD). I am transforming the view matrix, using the eye, look-at, and up vectors. I do not know how to correctly extract the six planes for the view frustum. Well, I know how to SETUP the planes, but I do not know which matrices to multiply before I do the extraction. Would it be: World · View View · Projection or World · View · Projection Any answers or a code for setting up a frustum would be greatly appreciated. Thanks everyone.

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Share on other sites should answer any most questions. If there is something specific not answered in there (or either of it''s associated linked articles), then ask away... I''m sure someone will be able to help when we know exactly where your trouble lies.

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Here's what i do

D3DXMatrixLookAtLH( &matView, &Camera.from,&,&Camera.up);
d3ddevice->SetTransform( D3DTS_VIEW, &matView );

D3DXMatrixPerspectiveFovLH(&matProj, 1.0f, 1.0f, 0.01f, 1000.0f);
d3ddevice->SetTransform(D3DTS_PROJECTION, &matProj);
//calculate the vectors and planes for the frustrim


D3DXMatrixMultiply( &mat, &matView, &matProj );
D3DXMatrixInverse( &mat, NULL, &mat );

vecFrustum[0] = D3DXVECTOR3(-1.0f, -1.0f, 0.0f); // xyz

vecFrustum[1] = D3DXVECTOR3( 1.0f, -1.0f, 0.0f); // Xyz

vecFrustum[2] = D3DXVECTOR3(-1.0f, 1.0f, 0.0f); // xYz

vecFrustum[3] = D3DXVECTOR3( 1.0f, 1.0f, 0.0f); // XYz

vecFrustum[4] = D3DXVECTOR3(-1.0f, -1.0f, 1.0f); // xyZ

vecFrustum[5] = D3DXVECTOR3( 1.0f, -1.0f, 1.0f); // XyZ

vecFrustum[6] = D3DXVECTOR3(-1.0f, 1.0f, 1.0f); // xYZ

vecFrustum[7] = D3DXVECTOR3( 1.0f, 1.0f, 1.0f); // XYZ

for( INT i = 0; i < 8; i++ )
D3DXVec3TransformCoord( &vecFrustum[i], &vecFrustum[i], &mat );

D3DXPlaneFromPoints( &planeFrustum[0], &vecFrustum[0], &vecFrustum[1], &vecFrustum[2] ); // Near

D3DXPlaneFromPoints( &planeFrustum[1], &vecFrustum[6], &vecFrustum[7], &vecFrustum[5] ); // Far

D3DXPlaneFromPoints( &planeFrustum[2], &vecFrustum[2], &vecFrustum[6], &vecFrustum[4] ); // Left

D3DXPlaneFromPoints( &planeFrustum[3], &vecFrustum[7], &vecFrustum[3], &vecFrustum[5] ); // Right

D3DXPlaneFromPoints( &planeFrustum[4], &vecFrustum[2], &vecFrustum[3], &vecFrustum[6] ); // Top

D3DXPlaneFromPoints( &planeFrustum[5], &vecFrustum[1], &vecFrustum[0], &vecFrustum[4] ); // Bottom

//transform the frustum plane into world space


just look at the cull example in the sdk

[edited by - kapru on March 22, 2004 10:44:27 PM]

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