Dynamic VB, Particles, & Triangle Lists

Graphics and GPU Programming Programming

Started by duhroach October 08, 2004 10:03 AM

2 comments, last by duhroach 19 years, 6 months ago

226

Author

October 08, 2004 10:03 AM

I feel really stupid for asking this, But I haven't been able to figure out the problem: I'm creating a particle system. What I wish to do, is add the verts of each particle to a vertex buffer, then render that entire buffer in one signle "drawPrimitive" call. What's happening, is that it will only draw the very first triangle, and that's all. I know there will be questions about code, So i'll just post it ahead of time..


//Dx9Primitive.cpp

//Create()..
sxDx9Driver::Get_Device()->CreateVertexBuffer(numverts*sizeof(sxPrimVertex),	D3DUSAGE_WRITEONLY, 3DFVF_PRIMVERTEX,D3DPOOL_DEFAULT, m_vertHandle, NULL );

//Lock()..
m_vertHandle->Lock( 0, sizeof(m_inputVerts)*sizeof(sxPrimVertex), (void**)&m_finalVerts,0);

//UnLock()..
memcpy( m_finalVerts, m_inputVerts, sizeof(m_inputVerts)*sizeof(sxPrimVertex) );
 m_vertHandle->Unlock();

//Render()..
sxDx9Driver::Get_Device()->SetStreamSource( 0, m_vertHandle, 0, sizeof(sxPrimVertex) );

	sxDx9Driver::Get_Device()->SetFVF( D3DFVF_PRIMVERTEX );
	sxDx9Driver::Get_Device()->DrawPrimitive( D3DPT_TRIANGLELIST, 0, m_numVerts/3);

Everything works fine when I use triangle STRIPS in another class (Identical code except for D3DPT_TRIANGLELIST and number primitives (numverts-2)) I'm really lost on this, And can't find an example of what the heck is going on.. any ideas? ~Main [/source]

==Colt "MainRoach" McAnlisGraphics Engineer - http://mainroach.blogspot.com

Namethatnobodyelsetook

1,260

October 08, 2004 10:32 AM

sizeof(m_inputVerts)*sizeof(sxPrimVertex) should be m_inputVerts*sizeof(sxPrimVertex), I think.

Leoric

122

October 08, 2004 10:34 AM

Hi,

you create the VertexBuffer with the variable 'numverts' and afterwards render it with the variable 'm_numVerts'. Maybe m_numVerts has a value of 3 and therefore 3/3 = 1 triangle.

In addition, you lock and fill it with 'm_inputVerts'. That's three different variables. Perhaps their values do not match. Check the values of all that variables.

Another possibility is this:
'm_inputVerts' seems to be an array. You memcpy a memory chain of the size sizeof(m_inputVerts)*sizeof(sxPrimVertex). When I do a sizeof of an array, the size of one element of that array is returned. Perhaps that is just my setup ?!

Bye,
Leoric