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Migi0027

DX11 DX11 - Updating global buffers?

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Migi0027    4628

Hi guys! happy.png

 

So I'm in the process of improving my material system, and what I'm trying to accomplish now, using the reflection api, is to make the user able to assign their variable values by their name, going well for now, but!

 

Whenever I define a global variable in my shader, let us call it _mSize,  I can retrieve all kinds of information from it, it's offset, size, etc... These variables which aren't assigned to a buffer are put inside a global buffer (denoted as $Global in the docs), but is there any kind of way that I can modify/update this buffer, is it even possible?

 

Thank you, as usual. smile.png

-MIGI0027

Edited by Migi0027

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Starnick    1892

The $Globals constant buffer is not anymore special than the ones you explicitly declare, it'll show up through the reflection interfaces (probably always index 0). So if you already have a scheme going with querying meta data, and updating buffers with your variables, it's the same exact procedure.

Edited by Starnick

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tonemgub    2008


(probably always index 0)

Not if there's another buffer specifically declared at cb0. For this and other reasons, the compiler gives no guarantee that $Globals will be at a specific index, so you have to query it by name.

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Migi0027    4628

Alright, thanks for the input, really appreciate it! wink.png

 

I'll try and see if I can succeed in fetching the variables from the global buffer. What I guess that I do is simply query the variable by name, then find the buffer from that variable, and go on from there.

 

Thanks guys!

-MIGI0027

Edited by Migi0027

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Starnick    1892

 


(probably always index 0)

Not if there's another buffer specifically declared at cb0. For this and other reasons, the compiler gives no guarantee that $Globals will be at a specific index, so you have to query it by name.

 

 

True, true. I was thinking if you didn't explicitly assign any CB's to a register. But yeah "always" doesn't fit :)

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