DrawText method slows down on large files

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   Hello All,

I am using the DrawText method to create a PDF document from a Text file.

I am finding that at around 3000 pages the process slows down considerably and by target of 15000 pages is never reached.

Could someone guide me in what factors to look for or be aware of when creating large PDF files?

Snippet of code below:

    Do While Not EOF(hFile)  ' Loop until end of file.
        Line Input #hFile, mytextline ' Read line into variable.

        'Output text
        X = 1
        Y = Y + Line_Space

        'Draw text line
        Call QP.DrawText(X, Y, mytextline)

    Loop

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mburian Members Profile Find Members Posts Beginner Joined: 10 Jul 06 Location: Australia Status: Offline Points: 17	Post Options Post Reply Quote mburian Report Post Thanks(0) Quote Reply Topic: DrawText method slows down on large files Posted: 18 Mar 07 at 8:16PM
	Hello All, I am using the DrawText method to create a PDF document from a Text file. I am finding that at around 3000 pages the process slows down considerably and by target of 15000 pages is never reached. Could someone guide me in what factors to look for or be aware of when creating large PDF files? Snippet of code below: Do While Not EOF(hFile) ' Loop until end of file. Line Input #hFile, mytextline ' Read line into variable. 'Output text X = 1 Y = Y + Line_Space 'Draw text line Call QP.DrawText(X, Y, mytextline) Loop
	Mick Burian

ukobsa Members Profile Find Members Posts Senior Member Joined: 29 May 06 Location: Germany Status: Offline Points: 115	Post Options Post Reply Quote ukobsa Report Post Thanks(0) Quote Reply Posted: 19 Mar 07 at 12:17AM
	Mick, maybe I have an idea why it is slowing down. Can you make such a large pdf available? (if not too large: please mail it to support(at)quickpdf.org) Ulrich

mburian Members Profile Find Members Posts Beginner Joined: 10 Jul 06 Location: Australia Status: Offline Points: 17	Post Options Post Reply Quote mburian Report Post Thanks(0) Quote Reply Posted: 19 Mar 07 at 1:16AM
	Hi, The file being converted is a "text" file. Is this the file you would like?
	Mick Burian

ukobsa Members Profile Find Members Posts Senior Member Joined: 29 May 06 Location: Germany Status: Offline Points: 115	Post Options Post Reply Quote ukobsa Report Post Thanks(0) Quote Reply Posted: 19 Mar 07 at 3:14AM
	Mick, I have done a short test doing the following: - create fresh QuickPDF document - add 5000 new pages - on each page draw 30 text strings well, this last really a lot of time. I have tested it with a profiler and this shows me, that there are some procedures that really could need some optimizations (causing the long processing). So for the moment I cannot see anything to improve the performance without coding. It's maybe a silly question but if you simply want to convert some kind of a text file to PDF: can't you do that by printing the file on a PDF Printer like FreePDF? Ulrich

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: 19 Mar 07 at 3:27AM
	Hi Uli! Can you tell me the relevant procedures? Best regards, Ingo

ukobsa Members Profile Find Members Posts Senior Member Joined: 29 May 06 Location: Germany Status: Offline Points: 115	Post Options Post Reply Quote ukobsa Report Post Thanks(0) Quote Reply Posted: 19 Mar 07 at 3:52AM
	Ingo, have a look for - TPDFName.Output - TPDFPainter.MakeFloat - TPDFPainter.AddString - TPDFFont.FixText all of them make massive string operation with '+' which is causing a lot of internal string copying in Delphi. If this can be reduced then the procedures should be faster (especially when they are very often called). I'll send you the track from my profiler by email. HTH, Uli

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: 19 Mar 07 at 4:48AM
	Hi Uli! Thanks. I think since friday the community (we) should do the job again ;-) If everyone just does a little bit ... we'll get something big for all ;-) Best regards, Ingo

swb1 Members Profile Find Members Posts Debenu Quick PDF Library Expert Joined: 05 Dec 05 Location: United States Status: Offline Points: 100	Post Options Post Reply Quote swb1 Report Post Thanks(0) Quote Reply Posted: 19 Mar 07 at 10:01AM
	Delphi strings have a reputation for being slow. I am not certain this is true; however there are many discussions in internet groups covering various solutions to the string concatenation problem. A quick suggestion though: look to see whether large strings are passed into functions as var parameters or if they can be. This can help avoid making a copy of the string each time the function is called. Regards, Steve

marian_pascalau Members Profile Find Members Posts Debenu Quick PDF Library Expert Joined: 28 Mar 06 Location: Germany Status: Offline Points: 278	Post Options Post Reply Quote marian_pascalau Report Post Thanks(0) Quote Reply Posted: 19 Mar 07 at 11:28AM
	Hi there, if you realy bother only about text information why don't you use SetPageContents function (function name may differ). Produce a demo page grab it's contents, create your own content template and reproduce contents for each page. PS: pay carefull attention on fonts and images. Best regards, Marian

mburian Members Profile Find Members Posts Beginner Joined: 10 Jul 06 Location: Australia Status: Offline Points: 17	Post Options Post Reply Quote mburian Report Post Thanks(0) Quote Reply Posted: 02 Apr 07 at 3:26PM
	Hi, Sorry for not replying sooner. My process is generic in that every text file converted has different page dimensions which affect the scale factor of the text on each line. This is why I thought that I needed to process each line. I also need page breaks which are inserted in the text file. I hope this helps and thanks for all of your input. Mick
	Mick Burian