   Vertices not being drawn : Struct vs FVF problem
  Hi, I think my problem is that my custom vertex struct isn't the same size as the FVF defines says it should be-(problem is stated below the code)The Define -> #define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZRHW|D3DFVF_DIFFUSE|D3DFVF_TEX1) The Struct->struct VERTEX{float x, y, z, rhw;D3DCOLOR color;float fU,fV;};The setup -> for(unsigned i=0;i<=vertNum;i++){   lasso.z = 0.0f;lasso.rhw =1.0;lasso.color = D3DCOLOR_ARGB(250,255,150,255);lasso.fU = 0.0f;lasso.fV = 0.5f;}for(unsigned i=0;i<=vertNum;i++){lasso.x =(float)(Player.x + radius* sin((PI*2)/vertNum)*i));lasso.y =(float)(Player.y - radius* cos((PI*2)/vertNum)*i));}d3ddev->SetFVF(D3DFVF_CUSTOMVERTEX);d3ddev->SetTexture(0, NULL);d3ddev->DrawPrimitiveUP(D3DPT_TRIANGLESTRIP,vertNum,lasso,sizeof(VERTEX));It doesn't draw anything on the screen.However, when I put "sizeof(D3DFVF_CUSTOMVERTEX)" as the last parameter of DrawPrimitiveUP, it does draw some weird rectangles on the screen (and I'm trying to draw a circle).Thank you in advance,Adar.P.S.Here are some other render states I call(when the application starts)  d3ddev->SetRenderState(D3DRS_SRCBLEND, D3DBLEND_SRCALPHA); d3ddev->SetRenderState(D3DRS_DESTBLEND, D3DBLEND_INVSRCALPHA); d3ddev->SetRenderState(D3DRS_ALPHABLENDENABLE,TRUE);    d3ddev->SetRenderState(D3DRS_CULLMODE,D3DCULL_NONE);
  The problem is likely that your vertex buffer data doesn't match the primitvetype you're asking the device to draw. Your structure and FVF appear to match.However, you're telling the device the data is in triangle strip order, which it isn't.Currently, your vertex buffer is a list of vertices around a circle. Those vertices don't form triangles.The vertices in the buffer need to be in a particular order, different for triangle strips vs. a triangle list, etc. Take a look in the documentation for D3DPRIMITIVETYPE, and from there, the description for triangle strips. That should give you a better idea how to setup your vertex buffer.Also, search through the SDK examples for D3DPT_TRIANGLESTRIP and take a look at the way the vertex buffers are filled.Certainly post again is you have trouble setting it up.   ;  thanks for you reply Buckeye-The main problem is that it doesn't even draw a LineStrip, and even when it does, only one line is drawn, I am aware of the veritces representing only the outline of a circle, but it doesn't even draw that O_O, what am I doing wrong?   