# DX11 particle system with stream output not working

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I am working on particle system using DX11 stream output. But there are some issues with it and not working as expected. Here are the steps I am following.

Technique 1: to update stream buffer

    D3D11_SO_DECLARATION_ENTRY pDecl[] =
{

{ 0, "SV_POSITION", 0, 0, 4, 0 },
{ 0, "VELOCITY", 0, 0, 3, 0 },
{ 0, "AGE", 0, 0, 1, 0 },
{ 0, "TYPE", 0, 0, 1, 0 }
};



3. Create two buffers with flags: D3D11_BIND_VERTEX_BUFFER | D3D11_BIND_STREAM_OUTPUT .

technique 2: to render particles

Render:

1. set pixel shader to NULL and disable rasterization using OMSetDepthStencilState.
2. update one of the buffers by generating particles in geometry shader.
3. Set both buffer targets to NULL.
4. Use the above buffer to render particles.
5. Set both buffer targets to NULL.
6. swap the buffers.

The problem is that something going wrong while reading from stream buffers. Both the techniques when run individually, works fine and gives correct output but problem arises when stream buffer comes into the picture.
Is there anything i am missing?
Edited by rgc183

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