Constant buffers language spec - initial draft #419
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| third one and \texttt{w} or \texttt{a} is the fourth, and last element of the | ||
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| \p Shader constant that has a structure, array or matrix type must always be |
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I'm guessing the answer is "backwards compatibility" but is there a strong argument against something like
Shader constant that has a structure, array or matrix type must always be
16-byte row-aligned. Therefore it may not specify a packoffset-element
My first thought on why not is that it could create "unbalanced" code like
cbuffer MyConstants {
MyStruct Foo : packoffset(c0);
float Foo : packoffset(c1.x);
};
but beyond that I'm not sure. Since its necessary to check x/y/z anyways it seems like the change would complicate implementations
In the end, I guess I'd just like to hear your thoughts on why it was picked to be this. Personally I'm torn because I prefer the language consistency of keeping it but also dislike the idea of language feature that does "nothing"
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I have no idea why it was done like that. Maybe @tex3d would know?
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| \p For example | ||
| \begin{HLSL} | ||
| float4 CameraPos : register(c2); |
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Mostly asking for historical context. Why is it called a register in $Globasl but packoffset for the rest?
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My guess is there was just a single constant buffer $Globals before cbuffer blocks and packoffset were added, and register was an established annotation at that time. So it just got extended with a 'c' value and new meaning.
@tex3d - please correct me if I am wrong! :)
Adds constant buffers to the language spec.