Re: Bitwise OR and AND without bitwise operators....

CelticDaddio wrote:
I am working in a programming language (GLSL) which does not support
bitwise operators, but I need to perform the following types of
calculations:

float b = (float)((counts & maskb) >> offsetg) / gbitres;

I can do the bit shifts by

Bit Shift Right ... i >> N = i / 2^N,
Bit Shift Left... i << N = i * 2^N,

right, but how can I do the bitwise AND? or a bitwise OR?

the lsb of n would be n-((n/2)*2).
the 2nd lsb of n would be m = n/2; m-((m/2)*2)
etc.
Notice you can re-use some results if you work lsb to msb.
So just iterate bitwise yourself and add 2^k to your result when the
bitwise operation on the kth bit is 1.

I don't know if this is the fastest way, but without bitwise arithmetic
support (which is why I assume bitwise operations are reserved), I
would think any solution would have to iterate over the operand's bits.

.

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