find_locs.php

<?php

ini_set('memory_limit', '900M');
ini_set('display_errors', '1');

// set here the valid ranges for all coordinates
$min_x = -5000;
$max_x = 5000;
$min_y = -5000;
$max_y = 5000;
$min_z = -5000;
$max_z = 5000;

if (!isset($argv[1])) die('Usage: php find_locs.php <filename>');
$file = $argv[1];

/////////////////////////////////////
print "\r\nXSC positions in $file (floats separated by 0x29):\r\n";

$data = file_get_contents($file);
if ($data === false) die('Cannot open file');
$total = strlen($data);
$offset = 0;
while (($total - $offset) >= 15)
{
    check_valid_xsc_loc($data, $offset);
    $offset++;
}

/////////////////////////////////////
print "\r\nBulk positions in $file (consequtive floats):\r\n";

$handle = fopen($file, "r");
if ($handle === false) die('Cannot open file');

$x = NAN;
$y = NAN;
$z = NAN;
while (($x !== false) && ($y !== false) && ($z !== false))
{
    if (is_valid_loc($x, $y, $z))
    {
        printf("%.4f, %.4f, %.4f\r\n", $x, $y, $z);
        $x = NAN;
        $y = NAN;
        $z = NAN;
    }
    $x = $y;
    $y = $z;
    $z = read_float($handle);
}

fclose($handle);

function read_float($handle)
{
    $dword = fread($handle, 4);
    if ($dword === false) return false;
    if (strlen($dword) != 4) return false;
    return parse_float($dword);
}

function parse_float($dword)
{
    return array_pop(unpack("f", strrev($dword)));
}

function check_valid_xsc_loc($data, $offset)
{
    if ($data[$offset] != "\x29") return false;
    if ($data[$offset+5] != "\x29") return false;
    if ($data[$offset+10] != "\x29") return false;
    $x = parse_float(substr($data, $offset+1, 4));
    $y = parse_float(substr($data, $offset+6, 4));
    $z = parse_float(substr($data, $offset+11, 4));
    if (is_valid_loc($x, $y, $z))
    {
        printf("%.4f, %.4f, %.4f\r\n", $x, $y, $z);
        return true;
    }
    return false;
}

function is_valid_loc($x, $y, $z)
{
    global $min_x;
    global $max_x;
    global $min_y;
    global $max_y;
    global $min_z;
    global $max_z;
    if ($x === false) return false;
    if (!is_finite($x)) return false;
    if ($x > $max_x) return false;
    if ($x < $min_x) return false;
    if (abs($x) < 0.1) return false;
    if ($x == 1) return false;
    if ($x == -1) return false;
    if ($y === false) return false;
    if (!is_finite($y)) return false;
    if ($y > $max_y) return false;
    if ($y < $min_y) return false;
    if (abs($y) < 0.1) return false;
    if ($y == 1) return false;
    if ($y == -1) return false;
    if ($z === false) return false;
    if (!is_finite($z)) return false;
    if ($z > $max_z) return false;
    if ($z < $min_z) return false;
    if (abs($z) < 0.1) return false;
    if ($z == 1) return false;
    if ($z == -1) return false;
    return true;
}

?>