AW: [Gnash-commit] gnash ChangeLog server/asobj/Key.cpp server/aso...

[Benjamin Wolsey]

> > +    int byte_index = keycode >> 3;
> > +    int bit_index = keycode - (byte_index << 3);
> > +    uint8_t mask = ~(1 << bit_index);
> > +    if ((m_unreleased_keys[byte_index] & mask) != 
> > m_unreleased_keys[byte_index] ) return true;     ---------> [1]
> >
> >     return false;
> >  }

> Is this an attempt for optimization or fixing anything?  Any
> assumption for with [1]?
> eg. If there are 2 bits set within the same byte, [1] would always return 
> true.

> --zou

It works:

For example, keys A (position 2 in byte) and C (position 4) are pressed.

so: m_unreleased_keys[byte_index] = 10

if bit_index = 2, mask = ~(1 << 2) = 253

10 & 254 = 10 <-- false
10 & 253 = 8 <-- true.
10 & 252 = 10
10 & 201 = 2 <-- true (bit_index 8)
10 & 200 = 10

etc.

But you're right that it's a mess. The complement rubbish can go and a simple 
if ((m_unreleased_keys[byte_index] & (1 << bit_index)) != 0 ) will do.

--bwy





      __________________________________  
Alles was der Gesundheit und Entspannung dient. BE A BETTER MEDIZINMANN! 
www.yahoo.de/clever