How to draw text fit to page width without wrap?
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=2186
Printed Date: 26 Jun 25 at 12:43PM
Software Version: Web Wiz Forums 11.01 - http://www.webwizforums.com
Topic: How to draw text fit to page width without wrap?
Posted By: ExchangeViews
Subject: How to draw text fit to page width without wrap?
Date Posted: 13 Mar 12 at 7:24AM
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Hi,
I want to draw a text string on pdf to fit into page width but unable to calculate the textsize to be set to cover page width without wrapping into next line. Please help. EV |
Replies:
Posted By: edvoigt
Date Posted: 13 Mar 12 at 9:36AM
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Hi, look at here: pw := 150; // as variable to play with QP.SetMeasurementUnits(1); // unit mm QP.SetPageDimensions(pw, 300); QP.SetOrigin(0); // Bottomleft txt := 'This is to be fitted in a line'; QP.DrawText(0, 250, txt); // unfitted only to show the difference tsize := QP.GetTextSize; // old textsize twidth := QP.GetTextWidth(txt); // old textwidth QP.SetTextSize(tsize*pw/twidth); QP.DrawText(0, 200,txt); // now it fits in The goal is to have the textwidth as same as pagewidth. So we we correct textsize by pagewidth/textwidth to get textwidth equal to pagewidth. To find this look in the reference guide under text and get inspiration by names of functions. Then play with them. It helps ever. Cheers, Werner |
Posted By: ExchangeViews
Date Posted: 13 Mar 12 at 12:36PM
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Thanks a lot. Trick is working great.
when I use DrawRotatedText function with 0 degree, it is working fine but when I change degree to 45 or 60... it is not drawing in full width even i tried to calculate diagonal length using pw/cos(DegToRad(45)) to find out font size. Can you guide in this point?
Thanks in advance.
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Posted By: edvoigt
Date Posted: 13 Mar 12 at 1:23PM
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Hi, no real problem. Only more complicated, because you have to think the text being in a box. But not the lower left corner ist the point, where rotation has origin. The origin is on baseline. So I have to build a new explanation near to this: http://www.quickpdf.org/forum/tquickpdf0813drawtext_topic2074.html - http://www.quickpdf.org/forum/tquickpdf0813drawtext_topic2074.html I'll do it in the evening. Werner |
Posted By: edvoigt
Date Posted: 13 Mar 12 at 5:57PM
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Hi, here the solution with some decorations for better understanding. The kernel is much more short. QP.SetMeasurementUnits(1); // unit mm angle := 30; // degrees for DrawRotated, betwenn 0 and 360° QP.SetPageDimensions(210, 300); QP.SetOrigin(0); // Bottomleft txt := 'This is to be fitted for x-direction, not y'; x0 := 20; // borders in which we want to place the text x1 := 190; fitwidth := x1-x0; x := x0; y := 180; // startpoint // 1. fitting for 0 degrees factor := (fitwidth)/QP.GetTextWidth(txt); QP.SetTextSize(QP.GetTextSize*factor); QP.SetLineWidth(0.1); QP.SetFillColor(1, 0, 0); QP.DrawCircle(x, y, 0.7, 1); // mark referenzpoint QP.SetTextColor(0.75, 0.75, 0.75); QP.DrawText(x, y,txt); // to show the relation between box and baseline tw := QP.GetTextWidth(txt); th := QP.GetTextHeight; td := -QP.GetTextDescent; tt := th-td; QP.DrawBox(x, y+tt, tw, tt+td, 0); // box from bottom to top QP.SetLineColor(1, 0, 0); // baseline QP.DrawLine(x, y, x+tw, y); // now fitting for rotation QP.SetLineColor(0, 0, 1); salpha := sin(angle*pi/180); calpha := cos(angle*pi/180); // show x-borders QP.SetLineColor(1, 0, 0); QP.DrawLine(x0, y-50, x0, y+100); QP.DrawLine(x1, y-50, x1, y+100); // x-distance from the most left to most right point of box is to be calced as: factor := fitwidth/(calpha*tw + salpha*th); // there are 2 boxsides! QP.SetTextSize(QP.GetTextSize*factor); // new values for sizes td := -QP.GetTextDescent; tt := QP.GetTextBound(2); dx := salpha*(tt+td); tw := QP.GetTextWidth(txt); th := QP.GetTextHeight; QP.SetTextColor(0, 0, 0); QP.DrawRotatedText(x+dx-salpha*td, y, angle, txt); QP.SetLineColor(0, 0, 1); QP.DrawRotatedBox(x+dx, (y-td), tw, th, angle, 0); We have to notice, that we handle a Box, which is a container for the text. If we rotate it, the edges must not be parallel to pageborders. To get the needed size in x we add the projektion of long (textwidth) and short (textheight) edges of the box onto x-axis. This value we have to compare with our goal the with from border to border. So we get a factor to choose the right Textsize. And so it looks:  It is to see, there is no fully exact solution possible, without a lot of more work. It depends on the first and last character. A last "q" would be more near to right border and a "p" as first more far from left border. Be careful using the code. It is only correct for 0 to <90°. On 90° cos(alpha) is zero. So have a look on this, if dividing. The next issue is if you are in another quarter of coordinatesystem, you have to change some signs. For testing and understanding rotations it is a good idea, to set the refererencepoint in the center of page. So you can test four cases at one time and see the differences. Have fun, Werner |