Advanced MFC Programming

Chapter 9. Font
Here, member lfFaceName specifies the font name; lfHeight and lfWidth specify font size; lfWeight,
lfItalic, lfUnderline and lfStrikeOut specify font styles. Besides these styles, there are two other
styles that can be specified: lfEscapement and lfOrientation.
Under Windows 95, lfEscapement and lfOrientation must be assigned the same value when a font
is being created. If they are non-zero, the text will have an angle with respect to the horizontal border of the
window when it is displayed (Figure 9-1). To display text this way, we must assign the angle to both
lfEscapement and lfOrientation when creating the font, the unit of the angle is one tenth of a degree.
Please note that only True Type fonts can have such orientation.
Escapement angle
Figure 9-1. Font escapement
After a font is created, it can be selected into DC for outputting text. After the text output is over, it
must be selected out of the DC. This procedure is exactly the same with other GDI objects.
Sample 9.1\GDI demonstrates how to create and use a font with specified styles. It is a standard SDI
application generated by Application Wizard. In the sample, the user can choose any available font in the
system and set its styles (bold, italic, underline, etc). The face name of the font will be displayed in the
client window using the selected font, and the user can also set the escapement of the font.
Two variables are added to class CGDIDoc: CGDIDoc::m_fontDraw and CGDIDoc::m_colorFont. The
first variable is declared as a CFont type variable, it will be used to create the font. The second variable is
declared as a COLORREF type variable, it will be used to store the color of the text.
Besides font color, we also need to consider the background color of the text. A text can be displayed
with either a transparent or opaque background. In the latter case, we can set the background to different
colors. In order to display text in different styles, another Boolean type variable CGDIDoc::
m_bTransparentBgd is declared, it will be used to indicate if the background is transparent or opaque.
The following is the modified class CGDIDoc:
……
……
class CGDIDoc : public CDocument
{
protected:
CGDIDoc();
DECLARE_DYNCREATE(CGDIDoc)
CFont m_fontDraw;
COLORREF m_colorFont;
BOOL m_bTransparentBgd;
public:
CFont *GetCurrentFont(){return &m_fontDraw;}
COLORREF GetFontColor(){return m_colorFont;}
BOOL GetBgdStyle(){return m_bTransparentBgd;}
virtual ~CGDIDoc();
};
Besides the three new member variables, there are also three new member functions added to the class.
These functions allow the information stored in CGDIDoc to be accessible outside the class, they are
CGDIDoc ::GetCurrentFont(), CGDIDoc::GetFontColor() and CGDIDoc::GetBgdStyle().
The above variables are initialized in the constructor of class CGDIDoc:
CGDIDoc::CGDIDoc()
{
LOGFONT lf;
CClientDC dc(NULL);
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