I need help - I can help - DrawHTMLTextBox and text height

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DrawHTMLTextBox and text height

Printed From: Debenu Quick PDF Library - PDF SDK Community Forum
Category: For Users of the Library
Forum Name: I need help - I can help
Forum Description: Problems and solutions while programming with the Debenu Quick PDF Library and Debenu PDF Viewer SDK
URL: http://www.quickpdf.org/forum/forum_posts.asp?TID=2190
Printed Date: 26 Jun 25 at 12:45PM
Software Version: Web Wiz Forums 11.01 - http://www.webwizforums.com

Topic: DrawHTMLTextBox and text height

Posted By: Jan
Subject: DrawHTMLTextBox and text height
Date Posted: 14 Mar 12 at 9:10AM

Hi, I have a file in XSL-FO format and I want convert it into PDF.
And I have problem with difference of text height calculated at drawing/printing via C#
and at insert in PDF file.
In both environment I use 'pt' units.

Example XSL-FO:
<fo:block line-height="14.399999999999999pt" top="11.0pt" left="41.0pt" height="15.0pt" width="434.0pt" font-family="Times New Roman" font-size="12.0pt">Test text, test text, test text .... </fo:block>

Inserting into PDF:

pdf.SetMeasurementUnits(0); // 0 = 1/72 inch "per unit"
pdf.SetOrigin(1);

int idFont = pdf.AddTrueTypeFont("Times New Roman", 0);
pdf.SetHTMLNormalFont("Times New Roman", idFont);

string textHTML = "Test text, test text, test text .... ";
pdf.DrawHTMLTextBox(10, 10, 434, 15, textHTML);

int _height = pdf.GetHTMLTextHeight(434, textHTML);

Height of text at C# drawing/printing is lower than 15 pt,
at inserting into PDF (variable _height) is higher than 15 pt (15,768 exactly).

Difference in this case is about 6%.
Solution may be reduce font size at PDF creating by 6% and round down to integer,
but I do not consider this the best solution.

Can you help me?
Thanks

Replies:

Posted By: Jan
Date Posted: 19 Mar 12 at 12:26PM

I found, that value returned by GetHTMLTextHeight depends on value spacing parameter HTML text. Same single-line HTML text, same font, different spacing and different text height:

int iFontID = qp.AddTrueTypeFont("Times New Roman", 0);

qp.SetHTMLNormalFont("Times New Roman", iFontID);

string textHTML = "Test text test text";

qp.DrawHTMLTextBox(10, 350, 300, 200, textHTML);

double height = qp.GetHTMLTextHeight(300, textHTML);

textHTML = "Test text test text";

qp.DrawHTMLTextBox(10, 400, 300, 200, textHTML);

height = qp.GetHTMLTextHeight(300, textHTML);