subWrite

<?php
require('fpdf.php');

class PDF extends FPDF
{
function subWrite($h, $txt, $link='', $subFontSize=12, $subOffset=0)
{
    // resize font
    $subFontSizeold = $this->FontSizePt;
    $this->SetFontSize($subFontSize);
    
    // reposition y
    $subOffset = ((($subFontSize - $subFontSizeold) / $this->k) * 0.3) + ($subOffset / $this->k);
    $subX        = $this->x;
    $subY        = $this->y;
    $this->SetXY($subX, $subY - $subOffset);

    //Output text
    $this->Write($h, $txt, $link);

    // restore y position
    $subX        = $this->x;
    $subY        = $this->y;
    $this->SetXY($subX,  $subY + $subOffset);

    // restore font size
    $this->SetFontSize($subFontSizeold);
}
}
?>

<?php
require('subwrite.php');

$pdf=new PDF();
$pdf->AddPage();
$pdf->SetFont('Arial','B',12);

$pdf->Write(5,'Hello World!');
$pdf->SetX(100);
$pdf->Write(5,"This is standard text.\n");
$pdf->Ln(12);

$pdf->subWrite(10,'H','',33);
$pdf->Write(10,'ello World!');
$pdf->SetX(100);
$pdf->Write(10,"This is text with a capital first letter.\n");
$pdf->Ln(12);

$pdf->subWrite(5,'Y','',6);
$pdf->Write(5,'ou can also begin the sentence with a small letter. And word wrap also works if the line is too long!');
$pdf->SetX(100);
$pdf->Write(5,"This is text with a small first letter.\n");
$pdf->Ln(12);

$pdf->Write(5,'The world has a lot of km');
$pdf->subWrite(5,'2','',6,4);
$pdf->SetX(100);
$pdf->Write(5,"This is text with a superscripted letter.\n");
$pdf->Ln(12);

$pdf->Write(5,'The world has a lot of H');
$pdf->subWrite(5,'2','',6,-3);
$pdf->Write(5,'O');
$pdf->SetX(100);
$pdf->Write(5,"This is text with a subscripted letter.\n");

$pdf->Output();
?>