Change page format after writeHTML - html

Question

I generate page using writeHTML under TCPDF. My page is made of 3 blocs (top, middle, bottom). I rotate the top one by 180 and middle one by 90.
Final page must be A4 landscape.
It works fine (as you can see on the snap) except for a small detail: as the middle part turn of 90°, this mean BEFORE the rotation the height of this part is higher than the heigt of the A4 landscape.
The only way I've found to have a correct display even with a middle block of great height (before rotation), is to perform the rotation using an A3 Portrait page. As on the picture.
So 2 questions:
Any idea of another way of doing?
If there is no other option, is it possible to generate the PDF in A3 portrait (using WriteHTML) and AFTER, crop the page to save (output) only the top part of the page, so to have a A4 landscape? (using TCPDF, not "manually")
For those interested: As I've dynamic data, I need to search each time for the center of rotation and the translation I must apply to the bootom block for it goes up against the middle block after the rotation. For that, I add "tcpdf method" tag on my HTML template, perform a writeHTML which call functions GetX, GetY and save the coord. for rotaton and also relative position of middle and bottom block (for bottom block translation)
Then I "rollback", set the coord in the template and perform a second writeHTML.

Answer 1

Lemme guess. If it's longer, the page breaks and it only rotates the content that had fit on the page while also possibly throwing off values you were expecting for GetX and GetY?
Disable the automatic page break and it should work as you expect.
$pdf->SetAutoPageBreak(FALSE, 0);
This way, it'll just draw off-page where it needs to without a page break interfering.
Edit: However I was wrong, as noted in the comment, that GetY would return a coordinate outside of the page. It does not.
So, we'll need to do our height check on a larger page, and then redraw on a new (properly sized) page once we know what we need to for layout, and destroy the original.
You can do that with transactions or with AddPage and DeletePage.
I tested with AddPage and DeletePage.
//.....
$pdf = new TCPDF_HELPER('L', 'pt',
array(8*72,5*72), true, 'UTF-8', false);
// set auto page breaks
$pdf->SetAutoPageBreak(FALSE, 0);
// set image scale factor
$pdf->setImageScale(PDF_IMAGE_SCALE_RATIO);
$pdf->setFontSubsetting(true);
$fontname = TCPDF_FONTS::addTTFfont(dirname(__FILE__).'/playtime.ttf', 'TrueTypeUnicode', '', 96);
$pdf->setFont($fontname, '', 16);
//I'm using a points and a ridiculous 19 inch by 19 inch custom size.
//We'll use this one to get the proper offset with `GetY`
$pdf->AddPage('L', array(19*72, 19*72));
$pdf->SetXY(1, 45);
$pdf->setFillColor(255,255,230);
$column = <<<EOT
<p>WHITE APPLE COUNTRY HORSE STABLE BATTERY PIG SHEEP KANE CICI LOLIPOP</p>
<p>WHITE APPLE COUNTRY HORSE STABLE BATTERY PIG SHEEP KANE CICI LOLIPOP</p>
<p>WHITE APPLE COUNTRY HORSE STABLE BATTERY PIG SHEEP KANE CICI LOLIPOP ioj</p>
<p>WHITE APPLE COUNTRY HORSE STABLE BATTERY PIG SHEEP KANE CICI LOLIPOP ioj</p>
EOT;
//Get our multicell's final offset.
$pdf->WriteHTMLCell(80, '', '', 40, $column, 1, 2, 1, false, 'J', true);
$stopposition = $pdf->GetY();
//Now that we have our needed coordinates,
//Add a new page in our desired format.
$pdf->AddPage('L', array(8*72,5*72));
$pdf->StartTransform();
$pdf->Rotate(90, 40, 70);
$pdf->WriteHTMLCell(80, '', '', 40, $column, 1, 0, 1, true, 'J', true);
$pdf->StopTransform();
$pdf->SetX(20);
$pdf->SetY(-20);
$pdf->Write('', "End of column, pre-rotation: $stopposition pt");
//Delete our larger calculation page.
$pdf->DeletePage(1);
//.....

Answer 2

Even if EPB answer is a very interesting one and work in some cases, in my case the result was the same.
So i've found a different way of doing. It's NOT really a "pure answer" but a good trick.
I create my page in A3 Portrait and rotate the data in order to get all the data in the upper part.
Then, I use a tool named "pdfposter" which I call from PHP, in order to split the A3 portrait PDF in two A4 Landscape.
So, after the writeHTML() I do:
$path_a3 = __DIR__ . '/../tmp/a3.pdf';
$path_a4 = __DIR__ . '/../tmp/a4.pdf';
$pdf->Output($path_a3, 'F');
$pdfposter = "pdfposter -m a4 -p 2x1a4 ".$path_a3." ".$path_a4;
exec($pdfposter,$retArr, $retVal);
After that, I've a a4.pdf with two A4 pages.
Notice just one detail: the page made wih TCPDF with rotated data are NOT compatible with pdfposter 0.6! You have to install version 07.post1 (latest from Git).