Strange Problem Calculating FontSize for CreateFont function: "Doesn't"

[EdPellesC99]

   Hi I am changing my font using the CreateFont. It all works for me except the calculation for the em size from my point size.
I am getting some sort of default.

   Here:

   HFONT font;
   long lfHeight;\
   lfHeight = -MulDiv(12, GetDeviceCaps(hdc, LOGPIXELSY), 72);  //... logical height of font that is 12 point will be calculated.

   font = CreateFont(lfHeight,  //.............................int nHeight,   logical height of font
               0,  //........................................int nWidth,   logical average character width
               0,  //........................................int nEscapement,   angle of escapement
               0,  //........................................int nOrientation,   base-line orientation angle
               FW_NORMAL,  //...................int fnWeight,   font weight
               FALSE,  //...............................DWORD fdwItalic,   italic attribute flag
               FALSE,  //...............................DWORD fdwUnderline,   underline attribute flag
               FALSE,  //...............................DWORD fdwStrikeOut,   strikeout attribute flag
               ANSI_CHARSET,  //.............................DWORD fdwCharSet,   character set identifier
               OUT_DEFAULT_PRECIS,  //.............DWORD fdwOutputPrecision,   output precision
               CLIP_DEFAULT_PRECIS,  //.............DWORD fdwClipPrecision,   clipping precision
               PROOF_QUALITY,  //..........................DWORD fdwQuality,   output quality
               VARIABLE_PITCH|FF_DECORATIVE,  //....DWORD fdwPitchAndFamily,   pitch and family
               "Comic Sans MS");  //.........................LPCTSTR lpszFace   pointer to typeface name string
   SelectObject(hdc, font);\
   SetTextColor(hdc, RGB(240,240,96));

   I am getting my font and all other features I want (proven by changing). But I want to be able to control the text size.
In this line:

   lfHeight = -MulDiv(12, GetDeviceCaps(hdc, LOGPIXELSY), 72);  //... logical height of font that is 12 point will be calculated.

If a change 12 to 30, my text size does not change! No modification up or down affects the text !


  If I ignore calculation and hard code -40 (a "bigger" negative number).... no problem I get a big text size (obviously not 40 pt).

So hard coding a negative integer in .... -10 or -50, and my text size always goes up or down like it should.

   font = CreateFont(-40,  //.............................int nHeight,   logical height of font
               0,  //........................................int nWidth,   logical average character width
               0,  //........................................int nEscapement,   angle of escapement
               0,  //........................................int nOrientation,   base-line orientation angle
               FW_NORMAL,  //...................int fnWeight,   font weight
                                              etc etc.....

   What BIG thing am I doing wrong in this line:

   lfHeight = -MulDiv(12, GetDeviceCaps(hdc, LOGPIXELSY), 72);

I almost got to the finish line understanding the font change. But I seem to be stymied here (not a rare event).

   Thanks in advance,
   Ed
 

[EdPellesC99]

   Ed,

   If you would modify your line to:

   myHeight = -MulDiv(10, GetDeviceCaps(GetDC(hWnd), LOGPIXELSY), 72);

  You will find that all is well in the world of Pelles C.

  As Pelle's "100 + error message says".......... "try to improve yourself".


  Problem solved.

  Your welcome,
  Ed

[CommonTater]

  As Pelle's "100 + error message says".......... "try to improve yourself".

LOL... I nearly fell off my chair laughing the first time I saw that... and all over a misplaced closing brace.

[EdPellesC99]

   Yes,

   I always see it when I compile a console app w/ a windows.h, before I can add the -Ze option.

   I too laughed, and realized Pelle must have a good sense of humor.
...... Something that is good thing for all of us !

I just heard an NPR interview will Will Short, the puzzle guy of the New York Times...... he was saying that having a good
laugh helps us solve problems.

Researchers  have found that it puts us in a playfull mood, and that helps us think creatively
and solve problems........... and THAT is something we all need !!!!!!

(I laughed also at your username and avator!)

later, Ed