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HLSL bool array (revisited for DX11)

vvvv beta question
#1

Long time ago, @Kalle)) asked for bool4 arrays into the shader: ((forum:hlsl-bool-array#comment-25187
In my DX9 shader i used

bool4x4 flags <String uiname="8x2 FX flags";>;

to reserve 16 flags that apply to every mesh. This works fine.
The same format doesn’t create a pin in a DX11 shader. Do i need some semantic or descriptive costume for it to work? Or do i really have to waste 32bit for each flag?

#2

well if u have constant amount of flags u can do:

bool MyBool[16](16);
#3

use uint bitwise operations. for example checking if the 4th bit is true:

(input & 0x00000010) != 0

or more user friendly

(input & [uint)1 << 4](https://vvvv.org/documentation/uint)1-<<-4) != 0

this way you have 32 “bools” per uint.

#4

Thanks guys. Both solutions work.
The uint solution seems a bit cheaper on transfer costs, but bitwise operations won’t run below shader model 4.0.
The bool array solution is so easy! Two years ago, i must have expected that the contents of the array would be distributed across the spread of meshes, but obviously they’re not.

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