How do I perform bit operations in glsl

Question

How do I perform bit operations in glsl?

Using the regular C style bitwise operators |, &, ^, or ! does not work.

See example code here: http://stackoverflow.com/a/23730491/763355 — MoDJ, Nov 02 '15 at 23:45

score 9 · Answer 1 · edited Oct 07 '13 at 20:35

9

They have been introduced with GLSL 1.30 (OGL 3.0).

Depending on what you want to do, you could eventually emulate them with floating point operations, x & (2^n)-1 = frac(x/(2^n))*(2^n) for example, but you'll have to take care of floating point errors.

edited Oct 07 '13 at 20:35

Nathan Monteleone

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answered Nov 09 '09 at 13:16

Aszarsha

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Are there more examples like that? This AND operation is what I needed the most, but also some OR would come in handy... – St0fF Nov 27 '17 at 14:00
@St0fF If you can find a way to do `¬` (not gate) then you can combine it with `∧` (and gate) using DeMorgan's law to obtain `p ∨ q = ¬( ¬p ∧ ¬q )`. – Sep 26 '19 at 08:22

score 8 · Answer 2 · answered Dec 21 '09 at 07:29

8

You need to put either

#version 130

or

#extension GL_EXT_gpu_shader4 : enable

in the top of your shader to get access to the bit operators

answered Dec 21 '09 at 07:29

Chris Dodd

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How do I perform bit operations in glsl

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