Debugging Help (Movement Generator)

[Q695]

For some reason X, and Y are being rewritten (only option 1 is showing up but the other stuff is visible) when they're intrtnal to the function (subtracting 1).

<?php
function mapgen($x, $y){
global $con, $cx, $cy, $cz, $m_q, $m_w, $m_e, $m_a, $m_s, $m_d, $m_z, $m_x, $m_c;
$mx=$cx+$x;
$my=$cy+$y;

echo $x.",". $y;

$sql_m= "select * from map WHERE x=$mx AND y=$my AND z=$cz";
$result = mysql_query($sql_m, $con) or die ("can not generate result " . mysql_error());
$row_m = mysql_fetch_assoc($result);
//print_r($row_m);
//echo $mx . "," . $my;
if ($row_m)
{
echo "<img src='images/" . $row_m['img'] . "' alt='terain' height='20' width='20' />";

if ($x='-1' && $y='1')
{$m_q=1;}
else if($x='0' && $y='1')
{$m_w=1;}
else if($x='1' && $y='1')
{$m_e=1;}
else if($x='-1' && $y='0')
{$m_a=1;}
else if($x='0' && $y='0')
{$m_s=1;}
else if($x='1' && $y='0')
{$m_d=1;}
else if($x='-1' && $y='-1')
{$m_z=1;}
else if($x='0' && $y='-1')
{$m_x=1;}
else if($x='1' && $y='-1')
{$m_c=1;}
else
{
echo"error";
}

}
else
{
echo "<img src='images/clear.gif' height='20' width='20' alt='null'>";
}

}
?>

Edited September 25, 2012 by Q695

[Jessica]

For one thing, you need to use some variable names that MEAN something.

Next, actually explain what you are trying to do, what's not working, what you expect, what you get.

[kicken]

if ($x='-1' && $y='1')

 

= is an assignment, meaning you are assigning '-1' to $x and '1' to $y. If you want to test the value of $x against '-1' to see if they are equal, you need to use == (two equal signs)

 

[Q695]

X, and Y are geometry figures

 

the == solved it for the most part, just need to figure out the last bug on my own

[Jessica]

if you think in a month you'll remember what m_s, m_e, m_c, m_d, m_a and m_z are, then fine. x and y are obviously axes. The rest of it doesn't make any damn sense.