User:Strife Onizuka

From Second Life Wiki
Jump to navigation Jump to search

About Me

I'm an immigrant from URU. Was in all 3 of it's beta's.

Wiki Gnome (causing drama isn't why I'm here).

I have a webpage but haven't updated it in a few months...

Wiki's are the way of the future when it comes to making documentation Ad-hoc but eventually become static as graffiti grows with popularity as a way of controlling it.

also contribute to some other wiki's History Wiki AviSynth:BlindWanderer

When it comes to writing I tend to go towards concise. A short accurate description is better then a long equally accurate description; less to get confused with, easier to find the important information (because it is all important).

Downloads

Updates: Preview Download
[DMZ] [Preview]
[Agni] [Preview]
[Colo] [Preview]
[Siva] [Preview]
[Durga] [Preview]
[Aditi] [Preview]
[Soma] [Preview]
[Ganga] [Preview]
[Uma] [Preview]

TightList

See TightList

Float <-Union-> Integer

integer fui(float a){//union float to integer
    if(a){//is it non zero?
        integer b = (a < 0) << 31;//the sign, but later this variable is reused to store the shift
        if((a = llFabs(a)) < 2.3509887016445750159374730744445e-38)//Denormalized range check & last stirde of normalized range
            return b | (integer)(a / 1.4012984643248170709237295832899e-45);//this works because the math overlaps; saves cpu time.
        integer c = llFloor(llLog(a) / 0.69314718055994530941723212145818);//extremes will error towards extreme. following yuch corrects it.
        return (0x7FFFFF & (integer)(a * (0x1000000 >> b))) | (((c + 126 + (b = ((integer)a - (3 <= (a /= (float)("0x1p"+(string)(c -= (c == 128)))))))) << 23 ) | b);
    }//for grins, detect the sign on zero. it's not pretty but it works. the previous requires alot of unwinding to understand it.
    return ((string)a == (string)(-0.0)) << 31;
}

float iuf(integer a)
{//union integer to float
    return ((float)("0x1p"+(string)((a | !a) - 150))) * ((!!(a = (0xff & (a >> 23))) << 23) | ((a & 0x7fffff))) * (1 | (a >> 31));
}//will crash if the raw exponent == 0xff; reason for crash deviates from float standard; though a crash is warented.

As a specialized mode of transport, this is faster the Float2Hex and just as lossless.

string fuis(float a){//float union to base64ed integer
    if(a){//is it non zero?
        integer b = (a < 0) << 31;//the sign, but later this variable is reused to store the shift
        if((a = llFabs(a)) < 2.3509887016445750159374730744445e-38)//Denormalized range check & last stirde of normalized range
            b = b | (integer)(a / 1.4012984643248170709237295832899e-45);//the math overlaps; saves cpu time.
        else
        {
            integer c = llFloor(llLog(a) / 0.69314718055994530941723212145818);//extremes will error towards extremes. following yuch corrects it.
            b = (0x7FFFFF & (integer)(a * (0x1000000 >> b))) | (((c + 126 + (b = ((integer)a - (3 <= (a /= (float)("0x1p"+(string)(c -= (c == 128)))))))) << 23 ) | b);
        }
        return llGetSubString(llIntegerToBase64(b),0,5)
    }//for grins, detect the sign on zero. it's not pretty but it works. the previous requires alot of unwinding to understand it.
    if((string)a == (string)(0.0))
        return "AAAAAA";
    return "gAAAAA";
}

float siuf(string b)
{//base64ed integer union to float
    integer a = llBase64ToInteger(b);
    return ((float)("0x1p"+(string)((a | !a) - 150))) * ((!!(a = (0xff & (a >> 23))) << 23) | ((a & 0x7fffff))) * (1 | (a >> 31));
}//will crash if the raw exponent == 0xff; reason for crash deviates from float standard; though a crash is warented.

Float Compare

integer FloatCompare(float a, float b, integer c)
{//compare floats and allow for a margin of error, requires fui().
    if(a - b)//(c) Strife Onizuka 2006 
    {//they are not equal
        //First we convert the floats to integer form, as they would be in memory;
        integer a_i = fui(a);
        integer b_i = fui(b);
        integer a_e = (a_i >> 23) & 0xff;
        integer b_e = (b_i >> 23) & 0xff;
        if(!(a_e || b_e) || //to disable the +/- roll under support put a // just before the !
            ((a_i & 0x80000000) == (b_i & 0x80000000)))//sign match check
        {//start by getting and testing the difference, this is what limits c
            integer diff = a_e - b_e;//ugly is fast, basicly, it gets the mantissa, sets the sign on the mantisa,
            if(diff >= -1 || diff <= 1)//shifts it depending on exponent, finaly executes the test.
                if(llAbs(((((a_i & 0x7FFFFF) | (!!a_e << 23)) * ((a_i >> 31) | 1)) >> !~-diff) - 
                         ((((b_i & 0x7FFFFF) | (!!b_e << 23)) * ((b_i >> 31) | 1)) >> !~diff)) <= c)
                    jump out;
        }
        return (a > b) - (a < b);
    }
    @out;
    return 0;
}

FUI2HexFloat

string FUI2HexFloat(integer b)
{//Dump FUI float-integer to a hex-float string
    string c = "";
    integer d = 0;
    integer e = 0xff & (b >> 23);
    string f = "0x"+(string)(!!e) + ".";
    if(b & 0x80000000)
        f = "-"+ f;
    if(e ^ 127) c = "p" + (string)((e | !e) - 127);
    if((e = 0xfffffe & (b << 1)))
    {
        while(!((e >> d) & 0xf))
            d+=4;
        while(d < 24)
        {
            c = llGetSubString(hexc, b = 0xf & (e >> d), b) + c;
            d += 4;
        }
    }
    return f + c;
}

string Float2Hex(float a)
{//Another way to do Float2Hex, i wrote this for the heck of it; not because it's a good idea.
    return FUI2HexFloat(fui(a));
}

BitCount

integer bitcount(integer n)
{//MIT Hackmem 169, modified to work in LSL
    integer tmp = n - ((n >> 1) & 0x5B6DB6DB)//modified mask
                    - ((n >> 2) & 0x49249249);
    return (((tmp + (tmp >> 3)) & 0xC71C71C7) % 63) + (n < 0);
}