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DX11 Shader debugger in DX9

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I would like to do real shader-debugging on my Windows 7 PC: being able to capture a frame, select a pixel and step through its pixel shader. The real deal, just like I can on my Xbox 360 devkit. Which tools can I use for that on Windows 7?

Supposedly Visual Studio 2012 has a really good PIX inside, but this is only DX10 and DX11, while my game is still DX9. So I cannot use that.

Nvidia's Perfhud used to also be a nice graphics debugger (don't know if it had stepping through pixel shaders, though), but I cannot get Perfhud to work on my Windows 7 computer: it keeps giving the error that the drivers are not instrumented. Also, Perfhud doesn't seem to have been update in six years, suggesting it is simply dead.

So, what to do? Are there other debugging/profiling tools I could use for graphics?

My game is made in DX9 (with the Ogre engine), shader model 3.0 and I can switch between HLSL and CG, so either would be good. I use Windows 7 and have an Nvidia GTX480.

Thanks in advance! smile.png

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Like Yourself mentioned Nsight is the replacement for PerfHUD. Nsight is the only debugger availble for PC that actually debugs shaders on the hardware, all other debuggers work by emulating the shader on the host PC.

The old PIX for Windows will still work for debugging shaders (via emulation as mentioned above), however you can't install the Windows 7 hotfix that brought DX11.1 to Win7. With that hotfix PIX will crash. However it is possible to uninstall the hotfix and use PIX again.

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I am okay with software emulation, just as long as the results are correct, since I need it for debugging, not so much for profiling. smile.png

I had a look at Nsight before, but I got the impression it only does shader debugging in DX10/11, not in DX9. Am I misinterpreting the description here, then?

I had also found Intel GPA, but I had automatically assumed it would only support Intel videocards. Does it also fully function on Nvidia cards then? I also couldn't find any description of full shader debugging in the GPA description. It only mentions "Shader experiments" in their Product Brief, which suggests things like swapping shaders, not fully stepping through a shader for an individual pixel.

Since you are mentioning 3 different alternative (Nsight, GPA and PIX), which would be my best choice?

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It does look like you're correct regarding Nsight and DX9. Honestly it's been so long since I used DX9, so I hadn't checked what tools supported it. I think PIX might be your best bet here, it's only tool that I can confirm works for debugging DX9 shaders.

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Microsoft DirectX SDK June 2010 has 64bit PIX in the package, I just have it on my win7 and I succesfully debug 32bit dx9 applications. PLease, post your result wheather you got it or not, thanks.

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I tried PIX now and it indeed does exactly what I was looking for! biggrin.png

I did have trouble with PIX in the DirectX June 2010 SD,K giving some weird error when I tried to debug a pixel. But it turns out that the 32 bit PIX in the August 2007 SDK does work. Great, on to some good debugging fun!

Thanks for the advice, folks! smile.png

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weird error? You could have been more specific. Wasn't it alerting " Multisampled surfaces cannot be pixel shader debugged. " ?

Since PIX 2007 works fine, I wasn't particularly looking for a solution, but I guess newer PIX would of course be better, so if you know how to solve it, I'd love to hear the solution! smile.png

When I try to debug a shader for a specific pixel, I first get a popup that tell me PIX is going to "Enable Shader Debugging" in the DirectX Control Panel. I click Yes, I allow it to make changes through a Windows popup, and then I get the message "Shader debugging could not be enabled", and then "An error occurred while preparing to debug the shader".

I tried enabling shader debugging myself in all the DirectX control panels I could find (2007/2010 32/64bit), and also setting them to Debug instead of Release DirectX, but neither helped. PIX 2007 works fine right away. Edited by Oogst

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I have that same exact problem with PIX while trying to debug vertex or pixel shaders in my XNA project...  I guess I'll go see if the old version works for me.

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I have that same exact problem with PIX while trying to debug vertex or pixel shaders in my XNA project...  I guess I'll go see if the old version works for me.


If you're using XNA, make sure you check "Disable D3DX Analysis" in the Target Program tab of "More Options" in PIX.

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