   problems with a DrawPrimitiveUP
  hey guys, im trying to execute that:pd3dDevice->SetFVF(D3DFVF_XYZ|D3DFVF_DIFFUSE);for(float angle= 0.0f; (angle<= (2.0f * PI)) || n<=98; angle +=1.0f && n++){vectorLine[n].diffuse=D3DCOLOR_XRGB(255,255,255);vectorLine[n].x = 0 + (terra.raio1* (float)sin(angle));vectorLine[n].z = 0 + (terra.raio2* (float)cos(angle));pd3dDevice->DrawPrimitiveUP(D3DPT_LINESTRIP, 1, &vectorLine[n], sizeof(CUSTOMVERTEX));}it's inside my render function and it works perfectly... but just for the FIRST time the program enter in render.. its says like the access readin violation 0x0000000.. like a null pointer...so i debugged to see where the problem occurs and the program stop in this line when the program enter to render the second frame:pd3dDevice->DrawPrimitiveUP(D3DPT_LINESTRIP, 1, &vectorLine[n], sizeof(CUSTOMVERTEX));do i have to clean something before it renders a second time? my clear stat is like that:pd3dDevice->Clear(0, NULL, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, D3DCOLOR_XRGB(0,0,0), 1.0f, 0);thanks in advance.   
  line strip is at least 2 points you appear to be passing 1 for starters.   ;  oh man, ty a lot, i forgot about that ><it was the problem   