Well I have had this problem times before and still don't know how to fix this. My alpha render states are setup like this:
There are two main problems in this the fallowing picture.
device->SetTextureStageState(0, D3DTSS_ALPHAARG1, D3DTA_TEXTURE);
device->SetTextureStageState(0, D3DTSS_ALPHAOP, D3DTOP_SELECTARG1);
1) The point sprites show a very obvius blue square on the person model
2) The point sprites sometimes form blue squares on top of each other
I can fix problem 1 by drawing the point sprites last but I can't always do that. The second problem I got no clue with.
sorry for pic not being in this topic (couldn't get the attachment manager to work)