LogLuv HDR problem

Well your basic process sounds fine. Are you using the exact code Christer had posted on his blog? I'd made a few changes to avoid some precision issues...the code I used is here. I'd tried it with MSAA on a few platforms and never encountered a problem like the one you're getting. The only issue I did have at first was that I'd accidentally left alpha-testing on while rendering, and that left some "holes" where the alpha was 0.

It sounds like you might be having some problems with discontinuities though...you've gotta be careful in the decode since you divide by Y. If Y is 0 you could get weird results in the pixel shader, depending on the hardware, driver, and shader model (remember that in SM2.0 dividing by 0 gives you 0, but in SM3.0 it produces an undefined result). You might want to see if you can produce that situation, and then run it through PIX or something.

thanks for the tips
but I still couldn't find a solution, checked the .y division, and even put an If statement to avoid zero division. but couldn't fix it
and the decode/encode code is exactly the one that you mentioned in your website
I put up a little test program for HDR test, that you can see the problem for your self.
hdr test demo
edit the INI file and set AntiAlias=0 or (2,4,8,...) to run it with AA and without AA.
you can add "debug=1" line in the [common] group to debug it in nvPerfHud
and for the console commands press '~' and type "r_enablepostfx hdr 0" while running ro disable HDR

any more help is really appreciated

I will try it out when I get home later tonight, and see what results I get.

I use this without the log compression ... so I split up the value straight into two 8-bit channels ... but I also have a rather low luminance range in the image.
You might give that a try ...

Unfortunately I can't run your test app...I get a message box with this text:

Creating RT Texture Surface failedInvalid call

The log file has this:

Fri Mar 27 20:28:43 2009Initializing Hammer Engine v0.70 ...Resource Manager InitializedInitializing Direct3D9 renderer ...Resource 'texture@impact24_00.dds' LoadedResource 'font@fonts/impact24.font' LoadedResource 'shader@shaders/2d_bmp.shader' LoadedResource 'shader@shaders/2d_clr.shader' LoadedResource 'shader@shaders/3d_dbg_clr.shader' LoadedInitializing Shadow cache ...Exception: Creating RT Texture Surface failed - Invalid call @ hmrTexture_D3d9.cppHammer Engine Released

The debug runtimes say that the call failed because an invalid format was specified.

I'm running an ATI HD 4870, FYI.

oh, I didn't test it on ATI cards, do you know what is the common hardware shadow mapping format for ATI cards ?
I use a 2k, RGBX8 and D24S8 DepthStencil texture for my card. I also check for the availability of the hardware z-buffers and for your card it doesn't seem to be the problem.

anyway, thanks wolf and mjp, the problem is solved, it wasn't actually with the LogLuv encoding, I had a problem with Z-artifacts that messed up the encoding.

Oh you're using hardware shadow mapping? It's a little different for ATI vs. Nvidia. I forget exactly how it works (it's been a long time)...this sample should show you how to do it.