Amebis/wxWidgets
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Avoid unnecessary calls in wxGDIPlusContext::GetTextExtent()

Browse Source 
Don't always call several GDI+ functions when we often don't need their
results: only retrieve the cell descent, ascent and the line spacing if
we are going to really use any of these values.
This commit is contained in:
Vadim Zeitlin
2019-02-03 22:46:02 +01:00
parent 21a7ff2aa3
commit c08ea68b4a
1 changed files with 24 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

41
src/msw/graphics.cpp
View File

@@ -2111,33 +2111,40 @@ void wxGDIPlusContext::GetTextExtent( const wxString &str, wxDouble *width, wxDo
wxCHECK_RET( !m_font.IsNull(), wxT("wxGDIPlusContext::GetTextExtent - no valid font set") );
wxWCharBuffer s = str.wc_str( *wxConvUI );
FontFamily ffamily ;
Font* f = ((wxGDIPlusFontData*)m_font.GetRefData())->GetGDIPlusFont();
f->GetFamily(&ffamily) ;
// Get the font metrics if we actually need them.
if ( descent || externalLeading || (height && str.empty()) )
{
FontFamily ffamily ;
f->GetFamily(&ffamily) ;
REAL factorY = m_fontScaleRatio;
REAL factorY = m_fontScaleRatio;
// Notice that we must use the real font style or the results would be
// incorrect for italic/bold fonts.
const INT style = f->GetStyle();
const REAL size = f->GetSize();
const REAL emHeight = ffamily.GetEmHeight(style);
REAL rDescent = ffamily.GetCellDescent(style) * size / emHeight;
REAL rAscent = ffamily.GetCellAscent(style) * size / emHeight;
REAL rHeight = ffamily.GetLineSpacing(style) * size / emHeight;
// Notice that we must use the real font style or the results would be
// incorrect for italic/bold fonts.
const INT style = f->GetStyle();
const REAL size = f->GetSize();
const REAL emHeight = ffamily.GetEmHeight(style);
REAL rDescent = ffamily.GetCellDescent(style) * size / emHeight;
REAL rAscent = ffamily.GetCellAscent(style) * size / emHeight;
REAL rHeight = ffamily.GetLineSpacing(style) * size / emHeight;
if ( height && str.empty() )
*height = rHeight * factorY;
if ( descent )
*descent = rDescent * factorY;
if ( externalLeading )
*externalLeading = (rHeight - rAscent - rDescent) * factorY;
}
if ( height )
*height = rHeight * factorY;
if ( descent )
*descent = rDescent * factorY;
if ( externalLeading )
*externalLeading = (rHeight - rAscent - rDescent) * factorY;
// measuring empty strings is not guaranteed, so do it by hand
if ( str.IsEmpty())
{
if ( width )
*width = 0 ;
// Height already assigned above if necessary.
}
else
{