OpenEuphoria

RE: assembly

• Posted by Derek Parnell <ddparnell at bigpond.com> Oct 08, 2001
• 380 views

----- Original Message -----
From: "Jiri Babor" <jbabor at PARADISE.NET.NZ>
To: "EUforum" <EUforum at topica.com>
Subject: Re: RE: assembly



> -- decompose phl sequence - try something like this:
>
> a = repeat(0, 256)
> x1 = a
> x2 = a
> y1 = a
> y2 = a
>
> for b = 1 to 256 do
>     a = phl[b][2]
>     x1 = phl[b][1][1] - 2
>     x1 = phl[b][1][2] - 2
>     x1 = phl[b][1][1] + 1
>     x1 = phl[b][1][2] + 1
> end for
>
>
> -- then one level indexing is MUCH faster:
>
> for b = 1 to 256 do
>     if a[b] = i then
>         ellipse(a[b], 1, {x1[b], y1[b]}, {x2[b], y2[b]})
>     end if
> end for
>
Another optimisation could be to eliminate the sequence forming in the
ellipse call at run time.

 a = repeat(0, 256)
 xy1 = repeat({0,0}, 256)
 xy2 = repeat({0,0}, 256)

 for b = 1 to 256 do
     a[b] = phl[b][2]
     xy1[b][1] = phl[b][1][1] - 2
     xy1[b][2] = phl[b][1][2] - 2
     xy2[b][1] = phl[b][1][1] + 1
     xy2[b][2] = phl[b][1][2] + 1
 end for


  -- then one level indexing is MUCH faster:

 for b = 1 to 256 do
     if a[b] = i then
         ellipse(a[b], 1, xy1[b], xy2[b])
     end if
 end for

-----------
But back to the original question. To do this using assembly code would
require that you know the internal layout of sequences and that is not
published and may change from release to release. Instead you would have to
store the coordinates in RAM arrays rather than sequences.

---------
Derek