Coordinates from MySQL to HTML table (PHP, PDO, MySQL)

Question

I am creating game which uses MySQL database to create "playing field".

In my MySQL table I have two columns pointX and pointY , both INT . I could also use POINT , but in my case these two columns are better solution.

| id | pointX | pointY | player | game |
|----|--------|--------|--------|------|
| 1  | -2     | 1      | 7      | 10   |
| 2  | -3     | 2      | 5      | 10   |
| 3  | 2      | -2     | 2      | 10   |
| 4  | -2     | -1     | 1      | 10   |

I should produce HTML table from this MySQL table. Something like this, but with no coordinateheaders (below those are only for easier understanding):

|-----|----|----|----|----|----|----|
| Y/X | -3 | -2 | -1 | 0  | 1  | 2  |
|-----|----|----|----|----|----|----|
| -2  |    |    |    |    |    | 2  |
|-----|----|----|----|----|----|----|
| -1  |    | 1  |    |    |    |    |
|-----|----|----|----|----|----|----|
| 0   |    |    |    |    |    |    |
|-----|----|----|----|----|----|----|
| 1   |    | 7  |    |    |    |    |
|-----|----|----|----|----|----|----|
| 2   | 5  |    |    |    |    |    |
|-----|----|----|----|----|----|----|

Plus.. every <td> should have attribute data-cell , which includes coordinates, as example data-cell="-2x-1" .

What is the best way to get started?

Answer 1

$rng = $dbh->prepare('
  SELECT   MIN(pointX) AS minX, MIN(pointY) AS minY,
           MAX(pointX) AS maxX, MAX(pointY) AS maxY
  FROM     field
  WHERE    game = ?
  LOCK IN SHARE MODE
');
$qry = $dbh->prepare('
  SELECT   pointX, pointY, player
  FROM     field
  WHERE    game = ?
  ORDER BY pointX, pointY
');
$dbh->beginTransaction();
$rng->execute([$game_id]);
$qry->execute([$game_id]);
$dbh->rollBack();

$limits = $rng->fetch();
$player = $qry->fetch();
echo '<table>';
for ($y = $limits['minY']; $y <= $limits['maxY']; $y++) {
  echo '<tr>';
  for ($x = $limits['minX']; $x <= $limits['maxX']; $x++) {
    printf('<td data-cell="%dx%+dy">', $x, $y);
    if ($player and $player['pointX'] == $x and $player['pointY'] == $y) {
      echo htmlentities($player['player']);
      $player = $qry->fetch();
    } else {
      echo '&nbsp;';
    }
    echo '</td>';
  }
  echo '</tr>';
}
echo '</table>';

Answer 2

It looks like you are already off to a good start. Assuming the number of cells for X and Y as $xcells and $ycells, the next step I would take is to build your table like so:

echo "<table>";
for ($i = -3; $i < $ycells; i++) {
  echo "<tr>";
  for ($j = -3; $j < $xcells; j++) {
    echo "<td data-cell='" . $i . "y" . $j . "x'>";
  }
  echo "</tr>";
}
echo "</table>";