Directx weird alpha problems

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:

Code:

device->SetRenderState(D3DRS_ALPHABLENDENABLE, true);
device->SetRenderState(D3DRS_SRCBLEND, D3DBLEND_SRCALPHA);
device->SetRenderState(D3DRS_DESTBLEND, D3DBLEND_INVSRCALPHA);

device->SetTextureStageState(0, D3DTSS_ALPHAARG1, D3DTA_TEXTURE);
device->SetTextureStageState(0, D3DTSS_ALPHAOP, D3DTOP_SELECTARG1);

There are two main problems in this the fallowing picture.

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)
http://runehunter.byethost9.com/Alpha.png

if you don't plan on drawing anything after these point sprites, don't have them write to the depth buffer. That way they'll Z test against everything else in the scene, but not themselves.

Most systems draw anything with alpha blending last to avoid the artifact you're seeing.

Ok ya I didn't notice the zwriteenable, I just knew about the zenable. Everything for the most part works now, just gotta redo a few things to make them work. Thanks.

Also if you don't want to sort your billboards then you can do alpha testing. Most cards support this now and it's quite handy for simple objects.