Problems drawing on a PDF

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Hi,

i have a PDF where the function DrawBox returns 1. But there is nothing painted on the PDF after i save it and open it.
The security info of the document show me the following results:
Security Method: None
User Password: No
Owner Password: No
Printing: Fully Allowed
Changing the Document: Allowed
Content Copying or Extraction: Allowed
Authoring Comments and Form Fields: Allowed
Form Field Fill-in or Signing: Allowed
Content Accessibility Enabled: Allowed
Document Assembly: Allowed
Encryption Level: Blank
Opened with User password: No
Opened with Owner password: No
Variable Encryption Strength: None

The DrawBox functions works perfect for other PDFs with the same security info results. Only this PDF doesnt work. 
Now the question: what can be the reason for this behaviour and how can i check it?   
I am using Debenu Quick PDF Library 9.15

No problem to upload the PDF for further tests.

Jutta Kudermann

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Kudermann Members Profile Find Members Posts Beginner Joined: 02 Aug 13 Status: Offline Points: 3	Post Options Post Reply Quote Kudermann Report Post Thanks(0) Quote Reply Topic: Problems drawing on a PDF Posted: 02 Aug 13 at 11:23AM
	Hi, i have a PDF where the function DrawBox returns 1. But there is nothing painted on the PDF after i save it and open it. The security info of the document show me the following results: Security Method: None User Password: No Owner Password: No Printing: Fully Allowed Changing the Document: Allowed Content Copying or Extraction: Allowed Authoring Comments and Form Fields: Allowed Form Field Fill-in or Signing: Allowed Content Accessibility Enabled: Allowed Document Assembly: Allowed Encryption Level: Blank Opened with User password: No Opened with Owner password: No Variable Encryption Strength: None The DrawBox functions works perfect for other PDFs with the same security info results. Only this PDF doesnt work. Now the question: what can be the reason for this behaviour and how can i check it? I am using Debenu Quick PDF Library 9.15 No problem to upload the PDF for further tests. Jutta Kudermann

AndrewC Members Profile Find Members Posts Moderator Group Joined: 08 Dec 10 Location: Geelong, Aust Status: Offline Points: 841	Post Options Post Reply Quote AndrewC Report Post Thanks(0) Quote Reply Posted: 04 Aug 13 at 9:05AM
	Jutta, Can you try calling QP.NormalizePage(0); before calling DrawBox ? If it works then NormalizePage will need to be be called once for each page that you want to use DrawBox, DrawText etc.. Andrew.

Kudermann Members Profile Find Members Posts Beginner Joined: 02 Aug 13 Status: Offline Points: 3	Post Options Post Reply Quote Kudermann Report Post Thanks(0) Quote Reply Posted: 05 Aug 13 at 8:24AM
	Hi Andrew, thank you very much! Thats the solution. Jutta

Eric24 Members Profile Find Members Posts Team Player Joined: 28 Jun 09 Location: Dallas, TX Status: Offline Points: 29	Post Options Post Reply Quote Eric24 Report Post Thanks(0) Quote Reply Posted: 18 Aug 13 at 7:33PM
	Just curious, but why is this is the solution?

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3524	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 18 Aug 13 at 10:07PM
	Cause there's something special with this single pdf. Something curious happened while creating ... who knows? We don't have this pdf - so we won't know. But this all doesn't matter cause we've a main medecine "NormalizePage" ;-) Edited by Ingo - 18 Aug 13 at 10:09PM

AndrewC Members Profile Find Members Posts Moderator Group Joined: 08 Dec 10 Location: Geelong, Aust Status: Offline Points: 841	Post Options Post Reply Quote AndrewC Report Post Thanks(0) Quote Reply Posted: 19 Aug 13 at 1:07AM
	Eric, PDF files were never designed to be manipulated. They were almost designed as a readonly format until people want to start doing useful things with their PDF files such as splitting, merging, stamping etc.. When you create a new PDF it will start off with the origin point (0,0) in the bottom left corner, the rotation in 0 degrees and the units as points (ie. 72points per inch), a black pen and a white background. Many PDF's change these values in the content stream during the creation process. If is good practice to call SaveState ('q') as the very first call in the content stream and RestoreState ('Q') as the very last operation. Many PDF produces do not do restore the graphics state at the end so when DQPL appends drawing commands such as DrawText it can be affected by the unknown drawing state and so can be drawn at the wrong angle in the wrong color in the wrong position or even off of the page in many cases. NormalizePage is designed to place SaveState/RestoreState commands at the start and end of the contentstream(s) respectively so that the drawing state is known and can be trusted. NormalizePage works on 99.9% of problem PDF's and it generally recommended to be called before adding any text, graphics or logos to an existing PDF file. Sometimes PDF producers add more SaveState calls than RestoreState calls so NormalizePage(1) will attempt to count and then balance out the Save/Restore calls. Andrew.