D3DXComputeBoundingBox

I dunno if this is what u need, but this works for me:

LPDIRECT3DVERTEXBUFFER8 buf; D3DXVECTOR3 vMin, vMax; DWORD numVertices = mMesh->GetNumVertices(); BYTE * byteBuffer = new BYTE[numVertices]; DWORD fvf = mMesh->GetFVF(); mMesh->GetVertexBuffer(&buf); buf->Lock(0,0,&byteBuffer,D3DLOCK_READONLY); D3DXComputeBoundingBox((PVOID)byteBuffer,numVertices,fvf,&vMin,&vMax); rBound.fMinX = vMin.x; rBound.fMinY = vMin.y; rBound.fMinZ = vMin.z; rBound.fMaxX = vMax.x; rBound.fMaxY = vMax.y; rBound.fMaxZ = vMax.z; buf->Unlock(); delete [] byteBuffer;

Hope it helps...

P.S. It was ripped straight from my source, but it has the stuff u want in it i think

---------------

I finally got it all together...
...and then forgot where I put it.

A few things, perhaps.

the variables named:&m_minCoords,&m_maxCoords are able to be written too right?

The number of verts is right, when you debug?
Are you sure the FVF matches the mesh?

Instead of FAILED()
Try to use the DX equivs.

Edited by - Gorky on January 7, 2002 7:47:08 PM

Ok, I copied the code from AdmiralBinary (btw, it is exactly the type of code I wanted) and only changed the names of the variables. However, I still get an error. This time, however, it is a message box saying that there is an assertion error. After looking it up to see what it means, Gorky''s theory about m_minCoords and m_MaxCoords being unwriteable makes sense. But what could cause them to do that? They are public variables.

Additionally, using Admiral Binary''s code, the assertion error comes in the call to lock the vertex buffer. (that is the first line that needs to be commented out.) I am wondering about the D3DLOCK_READONLY flag, since it is an assertion error, but it does seem as if it is only reading it-- the vertex buffer is an "in" argument.

Finally, when I run it in the release version, it does not crash. However, I have not tested to see if the code actually works and either way I would like to solve this problem.

I can show you the constructor of the class as well, I doubt that will help, but here is the whole class as it is now:

class CLevelObject {
public:
CLevelObject();
void StoreBoundingBox();
CMesh m_ObjectMesh;
CFrame m_ObjectFrame;
D3DXVECTOR3 m_minCoords;
D3DXVECTOR3 m_maxCoords;

};
CLevelObject::CLevelObject() {
m_minCoords.x=0;
m_minCoords.y=0;
m_minCoords.z =0;
m_maxCoords.x=0;
m_maxCoords.y=0;
m_maxCoords.z =0;
/*I''m not sure about initializing these or not, i have tried it both ways and neither works, so im guessing it doesnt make much difference */
}

//stores in m_minCoords and m_maxCoords vectors with the
//min and max vertices of the object/mesh
void CLevelObject::StoreBoundingBox() {
//create a vertex buffer

LPDIRECT3DVERTEXBUFFER8 buf;
D3DXVECTOR3 vMin, vMax;
DWORD numVertices = m_ObjectMesh.m_pMesh->GetNumVertices();
char string[5];
ZeroMemory( &string, sizeof( string ) );
/* Convert the number of vertices to a string (for debugging)*/
itoa( numVertices, string, 10 );
SetError("The number of vertices is :");
SetError(string);
BYTE * byteBuffer = new BYTE[numVertices];
DWORD fvf = m_ObjectMesh.m_pMesh->GetFVF();
m_ObjectMesh.m_pMesh->GetVertexBuffer(&buf);
buf->Lock(0,0,&byteBuffer,D3DLOCK_READONLY);
D3DXComputeBoundingBox((PVOID)byteBuffer,numVertices,fvf,&vMin,&vMax);
buf->Unlock();
delete [] byteBuffer;
}


Thanks for your help so far, hopefully we can now fix the problem completely.

A vertice is bigger than a byte!

BYTE * byteBuffer = new BYTE[numVertices];


Make it bigger

Ok, now it works properly. After correcting the change that Gorky pointed out, all i had to do was delete the line which is
delete [] byteBuffer;

I guess I need to actually move that line to the Game_Shutdown() function.

Thanks for all your help!

Edited by - GameDev135 on January 8, 2002 5:43:06 PM