Key Compressor

Cross-posted from tips: two functioms to compress keys to reduce the memory requirements if you need to make large lists of them. Reduces a key from 36 to 22 characters, so you can store roughly 40% more in the same memory. Yays!

Note that the forum may have inserted spaces in the strings near the start - there should be no spaces in them, and no returns or anything similar. Also - technically chref doesn't need to be that long, but I left those in for future expansion to maybe actually do some proper data compression.

// 4 bits per char, boo.
string hexchars = "0123456789abcdef";

// 6 bits per char, yay!

string chref = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!@#$%^&*()[]{}?+-_\|',.<>~`;:";
                
string crunchkey(key thekey) {
   integer t;
   string skey = (string)thekey;
   integer buffbits = 0;
   integer buffval = 0;
   string outkey = "";
   
   for (t=0; t<36; t++) {
       string curchar = llGetSubString(skey,t,t);
       if (curchar != "-") {
           integer curval = llSubStringIndex(hexchars,curchar);
            
           buffval+=(curval << buffbits);
           buffbits+=4;
           if (buffbits > 5) {
              integer lval = buffval & 63;
              outkey += llGetSubString(chref,lval,lval);
              buffval = buffval >> 6;
              buffbits -= 6;
           } 
       }
   }
   outkey += llGetSubString(chref,buffval,buffval);
   return outkey;
}

key uncrunchkey(string crunched) {
  integer t;
  string outkey;
  integer buffbits = 0;
  integer buffval = 0;
  integer outchars = 0;
  
  for (t=0; t<22; t++) {
         string curchar = llGetSubString(crunched,t,t);
         integer curval = llSubStringIndex(chref,curchar);
         buffval += (curval << buffbits);
         buffbits += 6;
         while (buffbits > 3) {
             integer lval = buffval & 15;
             if (outchars < 32) outkey += llGetSubString(hexchars,lval,lval);
             outchars++;
             if (outchars == 8) outkey += "-";
             if (outchars == 12) outkey += "-";
             if (outchars == 16) outkey += "-";
             if (outchars == 20) outkey += "-";
             buffval = buffval >> 4;
             buffbits -= 4;
         }
        
  }
  return (key)outkey;
}

thats funny because I store 31 bit in a double-char.