User:Strife Onizuka/int2hexdword: Difference between revisions

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New page: I was thinking about something else when this crazy idea hit me on how to make a "better" int2hex function. It's really clever and should be faster in LSO (maybe even Mono). Anyway it was ...
 
Strife Onizuka (talk | contribs)
mNo edit summary
Line 4: Line 4:
string int2hexdword(integer I)
string int2hexdword(integer I)
{
{
//0xABCDEFGH
    //0xABCDEFGH
integer A = (I >> 2) & 0x3C000000;//not an unsigned rshift
    integer A = (I >> 2) & 0x3C000000;//not an unsigned rshift
integer B = (I & 0x0F000000) >>  4;
    integer B = (I & 0x0F000000) >>  4;
integer C = (I & 0x00F00000) >>  6;
    integer C = (I & 0x00F00000) >>  6;
integer D = (I & 0x000F0000) >>  8;
    integer D = (I & 0x000F0000) >>  8;
integer E = (I & 0x0000F000) << 14;
    integer E = (I & 0x0000F000) << 14;
integer F = (I & 0x00000F00) << 12;
    integer F = (I & 0x00000F00) << 12;
integer G = (I & 0x000000F0) << 10;
    integer G = (I & 0x000000F0) << 10;
integer H = (I & 0x0000000F) <<  8;
    integer H = (I & 0x0000000F) <<  8;
   
return llGetSubString(
    return llGetSubString(
llInsertString(
            llInsertString(
llIntegerToBase64(
                llIntegerToBase64(
A + B + C + D + 0xD34D3400
                    A + B + C + D + 0xD34D3400
- (0xF8000000 * (A / 0x28000000))
                    - (0xF8000000 * (A / 0x28000000))
- (0x03E00000 * (B / 0x00A00000))
                    - (0x03E00000 * (B / 0x00A00000))
- (0x000F8000 * (C / 0x00028000))
                    - (0x000F8000 * (C / 0x00028000))
- (0x00003E00 * (D / 0x00000A00))
                    - (0x00003E00 * (D / 0x00000A00))
),
                ),
4,
                4,
llIntegerToBase64(
                llIntegerToBase64(
E + F + G + H + 0xD34D3400
                    E + F + G + H + 0xD34D3400
- (0xF8000000 * (E / 0x28000000))
                    - (0xF8000000 * (E / 0x28000000))
- (0x03E00000 * (F / 0x00A00000))
                    - (0x03E00000 * (F / 0x00A00000))
- (0x000F8000 * (G / 0x00028000))
                    - (0x000F8000 * (G / 0x00028000))
- (0x00003E00 * (H / 0x00000A00))
                    - (0x00003E00 * (H / 0x00000A00))
)
                )
),
            ),
0,
            0,
7
            7
);
        );
}
}


default
default
{
{
state_entry()
    state_entry()
{
    {
llSay(0, int2hexdword(0));
        llSay(0, int2hexdword(0));
llSay(0, int2hexdword(0x13579BDF));
        llSay(0, int2hexdword(0x13579BDF));
llSay(0, int2hexdword(0xFDB97531));
        llSay(0, int2hexdword(0xFDB97531));
llSay(0, int2hexdword(-1));
        llSay(0, int2hexdword(-1));
}
    }
}
}
</lsl>
</lsl>

Revision as of 12:43, 7 July 2009

I was thinking about something else when this crazy idea hit me on how to make a "better" int2hex function. It's really clever and should be faster in LSO (maybe even Mono). Anyway it was a bunch of fun to write. It works by shifting the bits around so that it can feed the integer to llIntegerToBase64 and have it come out hex. The divides "/" can be replaced with ">=" with no ill effect (except the code won't run in LSLEditor without an explicit typecast). This was really fun code to write.

<lsl> string int2hexdword(integer I) {

   //0xABCDEFGH
   integer A = (I >> 2) & 0x3C000000;//not an unsigned rshift
   integer B = (I & 0x0F000000) >>  4;
   integer C = (I & 0x00F00000) >>  6;
   integer D = (I & 0x000F0000) >>  8;
   integer E = (I & 0x0000F000) << 14;
   integer F = (I & 0x00000F00) << 12;
   integer G = (I & 0x000000F0) << 10;
   integer H = (I & 0x0000000F) <<  8;
   
   return llGetSubString(
           llInsertString(
               llIntegerToBase64(
                   A + B + C + D + 0xD34D3400
                   - (0xF8000000 * (A / 0x28000000))
                   - (0x03E00000 * (B / 0x00A00000))
                   - (0x000F8000 * (C / 0x00028000))
                   - (0x00003E00 * (D / 0x00000A00))
               ),
               4,
               llIntegerToBase64(
                   E + F + G + H + 0xD34D3400
                   - (0xF8000000 * (E / 0x28000000))
                   - (0x03E00000 * (F / 0x00A00000))
                   - (0x000F8000 * (G / 0x00028000))
                   - (0x00003E00 * (H / 0x00000A00))
               )
           ),
           0,
           7
       );

}

default {

   state_entry()
   {
       llSay(0, int2hexdword(0));
       llSay(0, int2hexdword(0x13579BDF));
       llSay(0, int2hexdword(0xFDB97531));
       llSay(0, int2hexdword(-1));
   }

} </lsl>