Gday, I am trying to create a tiled map for my game, i have had this previously working using other xml methods but i had memory leaks and all sorts of errors. However i had a map load time of about 2.5 - 3 seconds.

So i rewrote all of the code using NSMutableStrings and NSStrings. After my best attempt at optomizing it i had a map load time of 10 - 11 seconds, which is far too slow.

So i have now rewritten the code using char* arrays, only to now have a load time of 18 seconds -_-.

Here is the latest code, i don't know much c so i could have easily botched the whole thing up.

            FILE* file = fopen(a, "r");
  fseek(file, 0L, SEEK_END);
  length = ftell(file);
  fseek(file,0L, SEEK_SET);
  char fileText[length +1];

  char buffer[1024];// = malloc(1024);
  while(fgets(buffer, 1024, file) != NULL)
  {
   strncat(fileText, buffer, strlen(buffer));

  }
  fclose(file);
  [self parseMapFile:fileText];




- (void)parseMapFile:(char*)tiledXML
{


 currentLayerID = 0;
 currentTileSetID = 0;
 tileX = 0;
 tileY = 0;

 int tmpGid;
 NSString* tmpName;
 int tmpTileWidth;
 int tmpTileHeight;
 int tilesetCounter = 0;

 NSString* tmpLayerName;
 int tmpLayerHeight;
 int tmpLayerWidth;
 int layerCounter = 0;
 tileX = 0;
 tileY = 0;
 int tmpFirstGid = 0;


 int x;
 int index;
 char* r;
 int counter = 0;
 while ((x = [self findSubstring:tiledXML substring:"\n"]) != 0)
 {
  counter ++;
  char result[x + 1];
  r = &result[0];
  [self substringIndex:tiledXML index:x newArray:result];
  tiledXML += x+2;
  index = 0;

  if (counter == 1)
  {
   continue;
  }
  else if (counter == 2)
  {
   char result1[5];
   index = [self getStringBetweenStrings:r substring1:"th=\"" substring2:"\"" newArray:result1];
   if (r != 0);
    mapWidth = atoi(result1);

   r += index +1;
   index = 0;
   index = [self getStringBetweenStrings:r substring1:"ht=\"" substring2:"\"" newArray:result1];
   if (r != 0);
    mapHeight = atoi(result1);

   r += index +1;
   index = 0;
   index = [self getStringBetweenStrings:r substring1:"th=\"" substring2:"\"" newArray:result1];
   if (r != 0);
    tileWidth = atoi(result1);

   r += index +1;
   index = 0;
   index = [self getStringBetweenStrings:r substring1:"ht=\"" substring2:"\"" newArray:result1];
   if (r != 0);
    tileHeight = atoi(result1);

   continue;

  }

  char result2[50];
  char result3[3];

  if ((index = [self getStringBetweenStrings:r substring1:" gid=\"" substring2:"\"" newArray:result3]) != 0)
  {

   tmpGid = atoi(result3);
   free(result2);
   if(tmpGid == 0)
   {
    [currentLayer addTileAtX:tileX y:tileY tileSetID:-1 tileID:0 globalID:0];
   } 
   else
   {
    [currentLayer addTileAtX:tileX 
            y:tileY 
          tileSetID:[currentTileSet tileSetID] 
          tileID:tmpGid - [currentTileSet firstGID] 
        globalID:tmpGid];
   }
   tileX ++;

   if (tileX > [currentLayer layerWidth]-1)
   {
    tileY ++;
    tileX = 0;
   }



  }
  else if ((index = [self getStringBetweenStrings:r substring1:"tgid=\"" substring2:"\"" newArray:result2]) != 0)
  {

   tmpFirstGid = atoi(result2);

   r += index +1;
   index = 0;
   index = [self getStringBetweenStrings:r substring1:"me=\"" substring2:"\"" newArray:result2];
   if (r != 0);
    tmpName = [NSString stringWithUTF8String:result2];


   r += index +1;
   index = 0;
   index = [self getStringBetweenStrings:r substring1:"th=\"" substring2:"\"" newArray:result2];
   if (r != 0);
    tmpTileWidth = atoi(result2);


   r += index +1;
   index = 0;
   index = [self getStringBetweenStrings:r substring1:"ht=\"" substring2:"\"" newArray:result2];
   if (r != 0);
    tmpTileHeight = atoi(result2);

  }
  else if ((index = [self getStringBetweenStrings:r substring1:"rce=\"" substring2:"\"" newArray:result2]) != 0)
  {


    currentTileSet = [[TileSet alloc] initWithImageNamed:[NSString stringWithUTF8String:result2] name:tmpName tileSetID:tilesetCounter firstGID:tmpFirstGid tileWidth:tmpTileWidth tileHeight:tmpTileHeight spacing:0];
    [tileSets addObject:currentTileSet];
    [currentTileSet release];
    tilesetCounter ++;


  }
  else if ((index = [self getStringBetweenStrings:r substring1:"r name=\"" substring2:"\"" newArray:result2]) != 0)
  {

   tileX = 0;
   tileY = 0;

   tmpLayerName = [NSString stringWithUTF8String:result2];

   r += index +1;
   index = 0;
   index = [self getStringBetweenStrings:r substring1:"th=\"" substring2:"\"" newArray:result2];
   if (r != 0);
    tmpLayerWidth = atoi(result2);


   r += index +1;
   index = 0;
   index = [self getStringBetweenStrings:r substring1:"ht=\"" substring2:"\"" newArray:result2];
   if (r != 0);
    tmpLayerHeight = atoi(result2);

   currentLayer = [[Layer alloc] initWithName:tmpLayerName layerID:layerCounter layerWidth:tmpLayerWidth layerHeight:tmpLayerHeight];
   [layers addObject:currentLayer];
   [currentLayer release];
   layerCounter ++;

  }


 }







}




-(void)substringIndex:(char*)c index:(int)x newArray:(char*)result
{
 result[0] = 0;
 for (int i = 0; i < strlen(c); i++)
 {
  result[i] = c[i];
  if (i == x)
  {
   result[i+1] = '\0';
   break;

  }

 } 
}


-(int)findSubstring:(char*)c substring:(char*)s
{
 int sCounter = 0;
 int index = 0;

 int d;
 for (int i = 0; i < strlen(c); i ++)
 {
  if (i > 500)//max line size
   break;
  if (c[i] == s[sCounter])
  {
   d = strlen(s);
   sCounter ++;

   if (d > sCounter)
   {

   }
   else
   {
    index = i - (d);
    break;
   }
  }
  else
   sCounter = 0;

 }
 return index;


}

-(int)getStringBetweenStrings:(char*)c substring1:(char*)s substring2:(char*)s2 newArray:(char*)result
{
 int sCounter = 0;
 int sCounter2 = 0;
 int index = 0;
 int index2 = 0;

 int d;
 for (int i = 0; i < strlen(c); i ++)
 {

  if (index != 0)
  {
   if (c[i] == s2[sCounter2])
   {
    d = strlen(s2);
    sCounter2 ++;

    if (d > sCounter2)
    {

    }
    else
    {
     index2 = i - (d);
     break;
    }
   }
   else
    sCounter2 = 0;


  }
  else
  {
   if (c[i] == s[sCounter])
   {
    d = strlen(s);
    sCounter ++;

    if (d > sCounter)
    {

    }
    else
    {
     index = i;

    }
   }
   else
    sCounter = 0;

  }

 }
 if (index != 0 && index2 != 0)
  [self substringIndex:(c + index+1) index:index2-index-1 newArray:result];

 return index;
}

(I know it's a lot of code to be putting in here) I thought the by using basic char arrays i could drastically increase the performance, at least over the initial node based code that i was replacing.

Thanks for all your efforts.