Please help me find a bug (DX9 Direct3D)

[Firlefanz]

Hello,

in my Game demo one of my Beta testers has a bug in a 3D sequence, the screens freezes, but in the background it continues.

I cannot reproduze this error myself, everything fine here.

I build in some error messages to find out where the errors come from.
They are coming from my 3D Particles. I included them from the SDK sample.

So here is the code how I render those particles (please not exceptionmsg is a function that writes the string into a textfile):

function CParticleSystem.Render(pd3dDevice: IDirect3DDevice9;nsize: single): HResult; 
var 
  p_Particle: P3DParticle; 
  pVertices: PPointVertex; 
  dwNumParticlesToRender: DWord; 
  Flags: DWord; 
  vPos, vVel: TD3DXVector3; 
  fLengthSq: Single; 
  dwSteps: DWord; 
  clrDiffuse: TD3DXColor; 
  dwDiffuse: DWORD; 
  i: Integer; 
begin 
  try 
  // Set the render states for using point sprites 
  pd3dDevice.SetRenderState(D3DRS_POINTSPRITEENABLE, iTRUE); 
  pd3dDevice.SetRenderState(D3DRS_POINTSCALEENABLE,  iTRUE); 
  pd3dDevice.SetRenderState(D3DRS_POINTSIZE,     FtoDW(nsize));   //GrA¬?AYe Partikel 
  pd3dDevice.SetRenderState(D3DRS_POINTSIZE_MIN, FtoDW(0.01)); 
  pd3dDevice.SetRenderState(D3DRS_POINTSCALE_A,  FtoDW(0.01)); 
  pd3dDevice.SetRenderState(D3DRS_POINTSCALE_B,  FtoDW(0.01)); 
  pd3dDevice.SetRenderState(D3DRS_POINTSCALE_C,  FtoDW(1.00)); 
  // Set up the vertex buffer to be rendered 
  pd3dDevice.SetStreamSource(0, m_pVB, SizeOf(TPointVertex),SizeOf(TPointVertex));    //dx9 letzter Param size in byte 
  pd3dDevice.SetFVF(D3DFVF_POINTVERTEX); 
  if m_pParticles=nil then exit; 
  p_Particle := m_pParticles; 
  if p_particle=nil then exit; 
  dwNumParticlesToRender := 0; 
  // Lock the vertex buffer.  We fill the vertex buffer in small 
  // chunks, using D3DLOCK_NOOVERWRITE.  When we are done filling 
  // each chunk, we call DrawPrim, and lock the next chunk.  When 
  // we run out of space in the vertex buffer, we start over at 
  // the beginning, using D3DLOCK_DISCARD. 
  Inc(m_dwBase, m_dwFlush); 
  if (m_dwBase >= m_dwDiscard) then m_dwBase:= 0; 
  if m_dwBase = 0 then Flags:= D3DLOCK_DISCARD else Flags:= D3DLOCK_NOOVERWRITE; 
  if m_pvb=nil then exit; 
  if failed(m_pVB.Lock(m_dwBase * SizeOf(TPointVertex), m_dwFlush * SizeOf(TPointVertex), 
   Pointer(pVertices), Flags)) then begin 
    commandoform.ExceptionMsg('ParticleLock'); 
    exit; 
  end; 
  // Render each particle 
  while Assigned(p_Particle) do 
  begin 
    vPos:= p_Particle.m_vPos; 
    vVel:= p_Particle.m_vVel; 
    fLengthSq := D3DXVec3LengthSq(vVel); 
    if &#40;fLengthSq < 1.0&#41;        then dwSteps &#58;= 2 
    else if &#40;fLengthSq <  4.00&#41; then dwSteps &#58;= 3 
    else if &#40;fLengthSq <  9.00&#41; then dwSteps &#58;= 4 
    else if &#40;fLengthSq < 12.25&#41; then dwSteps &#58;= 5 
    else if &#40;fLengthSq < 16.00&#41; then dwSteps &#58;= 6 
    else if &#40;fLengthSq < 20.25&#41; then dwSteps &#58;= 7 
    else                             dwSteps &#58;= 8; 
    D3DXVec3Scale&#40;vVel, vVel, -0.04 / dwSteps&#41;; 
    D3DXColorLerp&#40;clrDiffuse, p_Particle.m_clrFade, p_Particle.m_clrDiffuse, p_Particle.m_fFade&#41;; 
    dwDiffuse&#58;= D3DXColorToDWord&#40;clrDiffuse&#41;; 
    // Render each particle a bunch of times to get a blurring effect 
    for i&#58;= 0 to dwSteps - 1 do 
    begin 
      pVertices.v     &#58;= vPos; 
      pVertices.color &#58;= dwDiffuse; 
      Inc&#40;pVertices&#41;; 
      Inc&#40;dwNumParticlesToRender&#41;; 
      if &#40;dwNumParticlesToRender = m_dwFlush&#41; then 
      begin 
        // Done filling this chunk of the vertex buffer.  Lets unlock and 
        // draw this portion so we can begin filling the next chunk. 
        if failed&#40;m_pVB.Unlock&#41; then begin 
          commandoform.exceptionmsg&#40;'ParticleUnLock'&#41;; 
          exit; 
        end; 
        Result&#58;= pd3dDevice.DrawPrimitive&#40;D3DPT_POINTLIST, m_dwBase, dwNumParticlesToRender&#41;; 
        if FAILED&#40;Result&#41; then begin 
          commandoform.exceptionmsg&#40;'Rendererror DrawPrimitive'&#41;; 
          Exit; 
        end; 
        // Lock the next chunk of the vertex buffer.  If we are at the 
        // end of the vertex buffer, DISCARD the vertex buffer and start 
        // at the beginning.  Otherwise, specify NOOVERWRITE, so we can 
        // continue filling the VB while the previous chunk is drawing. 
        Inc&#40;m_dwBase, m_dwFlush&#41;; 
        if &#40;m_dwBase >= m_dwDiscard&#41; then m_dwBase&#58;= 0; 
        if m_dwBase = 0 then Flags&#58;= D3DLOCK_DISCARD else Flags&#58;= D3DLOCK_NOOVERWRITE; 
        if failed&#40;m_pVB.Lock&#40;m_dwBase * SizeOf&#40;TPointVertex&#41;, m_dwFlush * SizeOf&#40;TPointVertex&#41;, 
         Pointer&#40;pVertices&#41;, Flags&#41;&#41; then begin 
           commandoform.exceptionmsg&#40;'ParticleLock2'&#41;; 
           exit; 
        end; 
        dwNumParticlesToRender &#58;= 0; 
      end; 
      D3DXVec3Add&#40;vPos, vPos, vVel&#41;; 
    end; 
    if p_Particle.m_pNext=nil then exit; 
    p_Particle &#58;= p_Particle.m_pNext; 
  end; 
  // Unlock the vertex buffer 
  m_pVB.Unlock; 
  // Render any remaining particles 
  if &#40;dwNumParticlesToRender <> 0&#41; then 
  begin 
    Result&#58;= pd3dDevice.DrawPrimitive&#40;D3DPT_POINTLIST, m_dwBase, dwNumParticlesToRender&#41;; 
    if FAILED&#40;Result&#41; then Exit; 
  end; 
  // Reset render states 
  pd3dDevice.SetRenderState&#40;D3DRS_POINTSPRITEENABLE, iFALSE&#41;; 
  pd3dDevice.SetRenderState&#40;D3DRS_POINTSCALEENABLE,  iFALSE&#41;; 
  Result &#58;= S_OK; 
  except 
    commandoform.exceptionmsg&#40;'Rendererror Particles'&#41;; 
  end; 
end;

My betatester reports the error is Particlelock and then it freezes.

Here is the code I use to render the particles:

//fA¼r partikel setzen 
    setrenderstate(d3drs_alphablendenable,dword(true)); 
    setrenderstate(d3drs_srcblend,d3dblend_srcalpha); 
    setrenderstate(d3drs_destblend,d3dblend_destalpha); 
    setmaterial(m_pParticleMaterial); 
    try 
    if m_pParticleTexture<>nil then SetTexture&#40;0, m_pParticleTexture &#41; 
    else exceptionmsg&#40;'3D Particle Nil'&#41;; 
    except 
      exceptionmsg&#40;'3D Particle Error'&#41;; 
    end; 
    setTextureStageState&#40;0, D3DTSS_COLORARG1, D3DTA_Texture&#41;; 
    setTextureStageState&#40;0, D3DTSS_COLOROP, D3DTOP_selectarg1&#41;; 
    setTextureStageState&#40;1, D3DTSS_COLOROP, D3DTOP_disable&#41;; 
    m_pParticleSystem.Render&#40;XenScreen.Device,0.3&#41;; 
    setrenderstate&#40;d3drs_alphablendenable,dword&#40;false&#41;&#41;; 
    setrenderstate&#40;d3drs_specularenable,dword&#40;false&#41;&#41;; 
    //fA¼r skybox setzen 
    setTextureStageState&#40;0, D3DTSS_COLOROP, d3dtop_modulate&#41;; 
    setTextureStageState&#40;1, D3DTSS_COLOROP, d3dtop_modulate&#41;; 
    setRenderState&#40;D3DRS_NORMALIZENORMALS, 0&#41;; 
    setTextureStageState&#40;1, D3DTSS_TEXCOORDINDEX, D3DTSS_TCI_PASSTHRU or 1&#41;; 
    setTextureStageState&#40;1, D3DTSS_COLOROP, D3DTOP_DISABLE&#41;;

So do you have any idea, how to fix that bug?

I have a htm file with the devicecaps of my testers graficx card here:

http://www.ericbehme.de/download/DeviceCaps.htm

Any idea how to fix that error or at least make the screen not freeze or what to do next?

Thanks a lot,
Firle