[Timiditas]

Is this what you call "expensive", if called everytime a bullet is fired ingame... ?

PHP Code:


#pragma semicolon 1

#include <sourcemod>
#include <sdktools>
#include <profiler>

#define PLUGIN_VERSION "1.1c"
new String: weaponlist[][] = { "ak47", "m4a1", "awp", "deagle", "mp5navy", "aug",
                                                                "p90", "famas", "galil", "scout", "g3sg1", "hegrenade",
                                                                "usp", "glock", "m249", "m3", "elite", "fiveseven",
                                                                "mac10", "p228", "sg550", "sg552", "tmp", "ump45",
                                                                "xm1014", "knife" };
new hashlist[] = { 322, 312, 328, 610, 725, 317, 226, 520, 521, 558, 425, 931, 344,
                                        528, 283, 163, 531, 971, 403, 280, 382, 386, 337, 452, 433, 525 };
//hashlist is generated by adding up all ascii chars PLUS the numeric value of each char if they are numeric
//e.g. m3 = 109+51+3
//this will certainly not work on much strings, but does not generate any collisions on this short weapon list

get_weapon_hash(const String: weapon_name[])
{
    new hash, WPlen = strlen(weapon_name);
    for(new I = 0;I < WPlen;I++)
    {
        decl String:inmid[2];
        strcopy(inmid,2,weapon_name[i]);
        //new char:inmid = weapon_name[i];
        hash += inmid[0];
        if(IsCharNumeric(inmid[0]))
            hash += StringToInt(inmid);
    }
    
    new loop_break = 0, index = 0, hWPsize = sizeof(hashlist);
    
    while ((loop_break == 0) && (index < hWPsize))
    {
        if (hash == hashlist[index])
            loop_break++;
        index++;
    }

    if (loop_break == 0)
        return -1;
    else
        return index - 1;
}

get_weapon_index(const String: weapon_name[])
{
    new loop_break = 0, index = 0, sWPsize = sizeof(weaponlist);
    
    while ((loop_break == 0) && (index < sWPsize))
    {
        if (strcmp(weapon_name, weaponlist[index], true) == 0)
            loop_break++;
        index++;
    }

    if (loop_break == 0)
        return -1;
    else
        return index - 1;
}








public Plugin:myinfo = {
    name = "stringtest",
    author = "Timiditas",
    description = "string hashing",
    version = PLUGIN_VERSION,
    url = "nowhere to run"
};

public OnPluginStart() {
    RegConsoleCmd("hash", fhash);
    RegConsoleCmd("find", find);
}

public Action:fhash(client, args)
{
    if (args != 1)
    {
        ReplyToCommand(client, "usage: hash <anystring>");
        return Plugin_Handled;
    }
    decl String:argument[255];
    GetCmdArg(1, argument, 255);
    new Handle:myProf = CreateProfiler();
    decl IDX;
    StartProfiling(myProf);
    IDX = get_weapon_hash(argument);
    StopProfiling(myProf);
    new Float:TheTime = GetProfilerTime(myProf);
    CloseHandle(myProf);
    ReplyToCommand(client, "Returned index: %i, HPT needed in seconds: %f",IDX,TheTime);
    return Plugin_Handled;
}

public Action:find(client, args)
{
    if (args != 1)
    {
        ReplyToCommand(client, "usage: find <anystring>");
        return Plugin_Handled;
    }
    decl String:argument[255];
    GetCmdArg(1, argument, 255);
    new Handle:myProf = CreateProfiler();
    decl IDX;
    StartProfiling(myProf);
    IDX = get_weapon_index(argument);
    StopProfiling(myProf);
    new Float:TheTime = GetProfilerTime(myProf);
    CloseHandle(myProf);
    ReplyToCommand(client, "Returned index: %i, HPT needed in seconds: %f",IDX,TheTime);
    return Plugin_Handled;
} 


Performance results below:

] find ak47
Returned index: 0, HPT needed in seconds: 0.000001
] hash ak47
Returned index: 0, HPT needed in seconds: 0.000003
] find knife
Returned index: 25, HPT needed in seconds: 0.000002
] hash knife
Returned index: 25, HPT needed in seconds: 0.000003
] find m3
Returned index: 15, HPT needed in seconds: 0.000002
] hash m3
Returned index: 15, HPT needed in seconds: 0.000003
] find fiveseven
Returned index: 17, HPT needed in seconds: 0.000002
] hash fiveseven
Returned index: 17, HPT needed in seconds: 0.000003
] find UNKNOWNSTRING
Returned index: -1, HPT needed in seconds: 0.000002
] hash UNKNOWNSTRING
Returned index: -1, HPT needed in seconds: 0.000004

So simply comparing the INTs is faster of course, but the required hashing at the beginning of get_weapon_hash() makes it slower.


~~edit

Actually, if you pack it into two loops, the results differ significantly.

PHP Code:

public Action:fhash(client, args)
{
    if (args != 1)
    {
        ReplyToCommand(client, "usage: hash <anystring>");
        return Plugin_Handled;
    }
    decl String:argument[255];
    GetCmdArg(1, argument, 255);
    new Handle:myProf = CreateProfiler();
    decl IDX, Float:Times;
    for(new j = 1;j<1001;j++)
    {
        StartProfiling(myProf);
        for(new i = 1;i<1001;i++)
        {
            IDX = get_weapon_hash(argument);
        }
        StopProfiling(myProf);
        Times += GetProfilerTime(myProf);
    }
    Times /= 1000.0;
    CloseHandle(myProf);
    ReplyToCommand(client, "Returned index: %i, HPT needed in seconds: %f",IDX,Times);
    return Plugin_Handled;
}

public Action:find(client, args)
{
    if (args != 1)
    {
        ReplyToCommand(client, "usage: find <anystring>");
        return Plugin_Handled;
    }
    decl String:argument[255];
    GetCmdArg(1, argument, 255);
    new Handle:myProf = CreateProfiler();
    decl IDX, Float:Times;
    for(new j = 1;j<1001;j++)
    {
        StartProfiling(myProf);
        for(new i = 1;i<1001;i++)
        {
            IDX = get_weapon_index(argument);
        }
        StopProfiling(myProf);
        Times += GetProfilerTime(myProf);
    }
    Times /= 1000.0;
    CloseHandle(myProf);
    ReplyToCommand(client, "Returned index: %i, HPT needed in seconds: %f",IDX,Times);
    return Plugin_Handled;
} 


Results:

] find no
Returned index: -1, HPT needed in seconds: 0.001577
] hash no
Returned index: -1, HPT needed in seconds: 0.000444
] find no
Returned index: -1, HPT needed in seconds: 0.001581
] hash no
Returned index: -1, HPT needed in seconds: 0.000444
] find ak47
Returned index: 0, HPT needed in seconds: 0.000078
] hash ak47
Returned index: 0, HPT needed in seconds: 0.000750
] find knife
Returned index: 25, HPT needed in seconds: 0.001606
] hash knife
Returned index: 25, HPT needed in seconds: 0.000791
] find UNKNOWNSTRING
Returned index: -1, HPT needed in seconds: 0.001584
] hash UNKNOWNSTRING
Returned index: -1, HPT needed in seconds: 0.001692
] find m3
Returned index: 15, HPT needed in seconds: 0.001077
] hash m3
Returned index: 15, HPT needed in seconds: 0.000498
] find glock
Returned index: 13, HPT needed in seconds: 0.000948
] hash glock
Returned index: 13, HPT needed in seconds: 0.000729
] find hegrenade
Returned index: 11, HPT needed in seconds: 0.000764
] hash hegrenade
Returned index: 11, HPT needed in seconds: 0.001162
] find g3sg1
Returned index: 10, HPT needed in seconds: 0.000728
] hash g3sg1
Returned index: 10, HPT needed in seconds: 0.000960

The wiki says:

The compiler, in fact, is very poor at optimizing

I wonder how much of the 'poor' optimizations kick in in the above loops.