🚀 go-pugleaf

In article <90305.105824CXT105@psuvm.psu.edu> CXT105@psuvm.psu.edu (Christopher Tate) writes:
>In article <1990Oct31.182705.3184@light.uucp>, bvs@light.uucp (Bakul Shah) says:
>
>>- To justify posting this to a PostScript group, here is a faster
>>  version of basically the same algorithm:
>>
>>    /gcd {              % given m, n on the stack
>>      dup 3 1 roll mod  % leaves n, m mod n on the stack
>>      dup 0 eq {
>>        pop             % leaves n on the stack when done
>>      } {
>>        gcd             % find gcd of the new pair
>>      } ifelse
>>    } bind def
>>

[ stuff deleted ]

>And, for everyone who's been following this, the version of the GCD algorithm
>shown above IS much faster than mine -- use it instead!  Mine was a quick-
>and-dirty rewrite of a Rexx version of the algorithm, and so was not at all
>suited to the real stack-handling capabilities of PostScript.

I put in the newer version of "gcd" and it went a bit faster.  Even more
dramatic was to bind the for loop at the end, like this:

    0 3 limit
    {
       dup frac mul /phi exch def       % calculate phi
       /theta exch def                  % recalculate theta
       theta limit div 1.0 1.0 sethsbcolor    % go through all colors
       theta cos diff mul phi cos a mul add   % this is x
       theta sin diff mul phi sin a mul add   % this is y
       2 copy lineto stroke moveto      % same as x y lineto stroke x y moveto
    } bind for
%     ^^^^  (add "bind" here)

(Glenn) cvn pop

-- 
 Glenn Reid				RightBrain Software
 glenn@heaven.woodside.ca.us		PostScript/NeXT developers
 ..{adobe,next}!heaven!glenn		415-851-1785