Malcolm Lear wrote:
>Just a thought on speeding things up.
>How about using a 16 bit lookup table to rearrange the red and green bits some
>like this:
>
>m33RGB move.w (a4)+,d2 get B0
> move.w (a4)+,d3 get RG
> move.w (a0,d3.w),d3 use lookup table to sort RG
> andi.w #$f800,d2 mask out B
> or.w d2,d3 combine RGB
>
>m33done move.w d3,d6 left pixel done, now do right
> swap d6
> ... inline repeat of above for right pixel
> move.l d6,(a3)+ two pixels to window save area
>
>The W bit would be created by the lookup table and depend on RG levels. Not a
>perfect solution but maybe acceptable.
But this not only ignores B2 but puts the RGB bits in the wrong order for the
Q40 display (if RG table returned 00000WGG GGGRRRRR then you would still need to
do a rotate after the OR.W). The criteria was if two or three bits in G2/R2/B2
are set then set RGB0 bit.
The most correct way I guess would be to add R2-0 + G2-0 + B0-2 and set RGB0 if
the result is greater than half maximum value (ugh!). I still think I prefer
just using G2 since I feel RGB0 is effectively a luminance bit
Regards,
Dave.
