public function multiply(mat4 $other)
{
$result = [[0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0]];
$otherArray = $other->toArray();
for ($i = 0; $i < 4; $i++) {
for ($j = 0; $j < 4; $j++) {
for ($k = 0; $k < 4; $k++) {
$result[$i][$j] += $this->data[$i][$k] * $otherArray[$k][$j];
}
}
}
return new mat4($result);
}
public function testConstructorDefaultsToIdentityMatrix()
{
$matrix = new mat4();
$expectedArray = array(array(1, 0, 0, 0), array(0, 1, 0, 0), array(0, 0, 1, 0), array(0, 0, 0, 1));
$this->assertEquals($expectedArray, $matrix->toArray());
}