Click here to Skip to main content
15,867,771 members
Articles / Multimedia / GDI

Hershey Font wrapper class

Rate me:
Please Sign up or sign in to vote.
4.50/5 (8 votes)
28 Mar 2000 96.1K   4.4K   26   8
Using Hershey vector fonts for faster rendering

Sample Image - HersheyFont.gif

Recently when building a GIS display system, I ran into the problem of displaying characters at many different sizes, rotations (escapments), and in several typefaces all in the same view. Unfortunately, the redraw performance I was able to obtain using Windows' font routines was not very good. Reaching back to my past (and definitely showing my age), I decided to use the venerable "Hershey" vector fonts.

All of the font management and display is wrapped up in the class SMFontUtil, the use of which is illustrated in the FontDemo program included. The only method of any real consequence is:

C++
void SMFontUtil::DrawString(
	CDC * pDC,            //device context to draw to
	CPoint pStart,        //starting point
	double pRotation,     //rotation angle clockwise in radians (0 = 12:00)
	double pCharWidth,    //width of each character
	double pCharHeight,   //height of each character
	FONT_TYPE pFontType,  //the font to use
	CString pString)      //the string

NOTE: For this article, I hard-coded the path so that the font definition data (found in FontData.zip) must reside in C:\HersheyFonts. In the real system, this is stored on a server with the GIS data.

The original Hershey font character codes do not match well ASCII. I have built a translation table that maps ASCII character and font to a Hershey character. The included fonts are:

  • SMALL_SIMPLEX
  • SMALL_DUPLEX
  • SIMPLEX
  • DUPLEX
  • TRIPLEX
  • MODERN
  • SCRIPT_SIMPLEX
  • SCRIPT_DUPLEX
  • ITALLIC_DUPLEX
  • ITALLIC_TRIPLEX
  • FANCY
  • GOTHIC

I have also included a crude font editor that lets you edit the vertices and the translation table. To edit a character, right click on it in any view. To assign a hershey font to a ASCII font family pairing select the character in the numeric view and select "index save" from the menu. Switch to Xlated view and select the target cell, then select "Assign Index".

The font data resides in two files. The vector data, and the translation table I have supplied both the runtime version, and a human readable version in CSV format for those who wish to use them. The SMFontUtils class provides a method to convert from the CSV to the runtime. Again, please note that for the purposes of this article, the font definition data (FontData.zip) must be extracted into C:\HersheyFonts.

License

This article has no explicit license attached to it, but may contain usage terms in the article text or the download files themselves. If in doubt, please contact the author via the discussion board below.

A list of licenses authors might use can be found here.


Written By
United States United States
This member has not yet provided a Biography. Assume it's interesting and varied, and probably something to do with programming.

Comments and Discussions

 
QuestionHow faster ? Pin
Alexandre GRANVAUD8-Sep-09 20:19
Alexandre GRANVAUD8-Sep-09 20:19 
GeneralProblem editing new symbol Pin
andywolpert19-Sep-05 10:50
andywolpert19-Sep-05 10:50 
GeneralPermission to use the class Pin
allanwright1-Mar-03 13:01
allanwright1-Mar-03 13:01 
GeneralWow! Pin
Swinefeaster12-Aug-02 0:06
Swinefeaster12-Aug-02 0:06 
GeneralRe: Wow! Pin
rakkar13-Nov-02 13:23
rakkar13-Nov-02 13:23 
GeneralRe: Wow! Pin
Chris Richardson17-Dec-02 14:04
Chris Richardson17-Dec-02 14:04 
GeneralRe: Wow! Pin
planetfall6-Jun-04 20:03
planetfall6-Jun-04 20:03 
GeneralRe: Wow! Pin
Paul Selormey17-Jun-04 23:10
Paul Selormey17-Jun-04 23:10 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Praise Praise    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.