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Re: [Public WebGL] Weird alpha issue.

If you go to about:config and set

Does that make a difference?

If yes, you have found a bug in our accelerated compositing code.
If no, we can't conclude anything.


----- Original Message -----
> Holy crap! I didn't expect *THAT*!
> So - I make a super-simple "test-app" version of my game (in another
> directory) and it produces white smoke where the main app generates
> dark. Next, I start to make my test application more and more like the
> real application and the smoke stubbornly stays white (ie it looks the
> same in Chrome as it does in Minefield).
> Eventually, I have PRECISELY the same lines of code in the test-app
> and
> the real-app - the same textures, the same shaders, the same
> absolutely
> everything. And they still look different!! I have NO clue WTF is
> making these two apps different.
> Er...except for the HTML that hosts the web page has:
> <body bgcolor="#000000"> in the 'real application'
> <body> in the 'test
> application'
> And lo and behold - when I change the HTML background color, the color
> of the smoke changes! So it looks like the problem is in the
> compositing step.
> I kinda suspect that I'm somehow getting a "destination alpha" frame
> buffer in Minefield and no "destination alpha" in Chrome - so when I
> write my translucent polygons into the frame buffer, I'm making the
> resulting canvas have translucent bits! Maybe that makes the
> compositor blend in the HTML page's background wherever I write my
> particles?
> I'm doing more experiments. I tried taking the SDK demo program
> "sdk/demos/google/particles" and changing the HTML background to black
> -
> but that didn't make a difference...so it's obviously a little more
> complicated than just that.
> Man - it's been about a decade since I last messed with destination
> alpha! I'm going to have to dust off my ancient copy of the "Red Book"
> and try to kick my memory into life!
> -- Steve
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