IDWriteFont* CreateDWriteFontFromGDIFamilyName(IDWriteFactory* factory, const WCHAR* gdiFamilyName)
{
IDWriteGdiInterop* dwGdiInterop;
HRESULT hr = factory->GetGdiInterop(&dwGdiInterop);
if (SUCCEEDED(hr))
{
LOGFONT lf = {};
wcscpy_s(lf.lfFaceName, gdiFamilyName);
lf.lfHeight = -12;
lf.lfWeight = FW_DONTCARE;
lf.lfCharSet = DEFAULT_CHARSET;
lf.lfOutPrecision = OUT_DEFAULT_PRECIS;
lf.lfClipPrecision = CLIP_DEFAULT_PRECIS;
lf.lfQuality = ANTIALIASED_QUALITY;
lf.lfPitchAndFamily = VARIABLE_PITCH;
IDWriteFont* dwFont;
hr = dwGdiInterop->CreateFontFromLOGFONT(&lf, &dwFont);
if (SUCCEEDED(hr))
{
return dwFont;
}
dwGdiInterop->Release();
}
return nullptr;
}
/* IDWriteGdiInterop methods */
virtual HRESULT STDMETHODCALLTYPE CreateFontFromLOGFONT(
LOGFONTW const *logFont,
IDWriteFont **font)
{
OutputDebugString("delegate_dwrite_gdi_interop::CreateFontFromLOGFONT");
HRESULT result;
UINT32 index;
BOOL exists;
result = mycoll_->FindFamilyName(logFont->lfFaceName, &index, &exists);
if (SUCCEEDED(result)) {
result = E_FAIL;
if (exists != FALSE) {
IDWriteFontFamily *family;
result = mycoll_->GetFontFamily(index, &family);
if (SUCCEEDED(result)) {
result = family->GetFirstMatchingFont(
(DWRITE_FONT_WEIGHT)logFont->lfWeight,
DWRITE_FONT_STRETCH_NORMAL,
DWRITE_FONT_STYLE_NORMAL,
font);
iunknown_release(family);
}
}
}
if (FAILED(result)) {
OutputDebugString("delegate_dwrite_gdi_interop::CreateFontFromLOGFONT -> fallback");
result = orig_this->CreateFontFromLOGFONT(logFont, font);
}
return result;
}
HRESULT
DWriteContext::SetLOGFONT(const LOGFONTW &logFont, float fontSize)
{
// Most of this function is copy from: http://msdn.microsoft.com/en-us/library/windows/desktop/dd941783(v=vs.85).aspx
HRESULT hr = S_OK;
IDWriteFont *font = NULL;
IDWriteFontFamily *fontFamily = NULL;
IDWriteLocalizedStrings *localizedFamilyNames = NULL;
if (SUCCEEDED(hr))
{
hr = mGdiInterop->CreateFontFromLOGFONT(&logFont, &font);
}
// Get the font family to which this font belongs.
if (SUCCEEDED(hr))
{
hr = font->GetFontFamily(&fontFamily);
}
// Get the family names. This returns an object that encapsulates one or
// more names with the same meaning but in different languages.
if (SUCCEEDED(hr))
{
hr = fontFamily->GetFamilyNames(&localizedFamilyNames);
}
// Get the family name at index zero. If we were going to display the name
// we'd want to try to find one that matched the use locale, but for
// purposes of creating a text format object any language will do.
wchar_t familyName[100];
if (SUCCEEDED(hr))
{
hr = localizedFamilyNames->GetString(0, familyName,
ARRAYSIZE(familyName));
}
if (SUCCEEDED(hr))
{
// If no font size was passed in use the lfHeight of the LOGFONT.
if (fontSize == 0)
{
// Convert from pixels to DIPs.
fontSize = PixelsToDipsY(logFont.lfHeight);
if (fontSize < 0)
{
// Negative lfHeight represents the size of the em unit.
fontSize = -fontSize;
}
else
{
// Positive lfHeight represents the cell height (ascent +
// descent).
DWRITE_FONT_METRICS fontMetrics;
font->GetMetrics(&fontMetrics);
// Convert the cell height (ascent + descent) from design units
// to ems.
float cellHeight = static_cast<float>(
fontMetrics.ascent + fontMetrics.descent)
/ fontMetrics.designUnitsPerEm;
// Divide the font size by the cell height to get the font em
// size.
fontSize /= cellHeight;
}
}
}
// The text format includes a locale name. Ideally, this would be the
// language of the text, which may or may not be the same as the primary
// language of the user. However, for our purposes the user locale will do.
wchar_t localeName[LOCALE_NAME_MAX_LENGTH];
if (SUCCEEDED(hr))
{
if (GetUserDefaultLocaleName(localeName, LOCALE_NAME_MAX_LENGTH) == 0)
hr = HRESULT_FROM_WIN32(GetLastError());
}
if (SUCCEEDED(hr))
{
// Create the text format object.
hr = mDWriteFactory->CreateTextFormat(
familyName,
NULL, // no custom font collection
font->GetWeight(),
font->GetStyle(),
font->GetStretch(),
fontSize,
localeName,
&mTextFormat);
}
if (SUCCEEDED(hr))
{
mFontWeight = static_cast<DWRITE_FONT_WEIGHT>(logFont.lfWeight);
mFontStyle = logFont.lfItalic ? DWRITE_FONT_STYLE_ITALIC
: DWRITE_FONT_STYLE_NORMAL;
}
SafeRelease(&localizedFamilyNames);
SafeRelease(&fontFamily);
SafeRelease(&font);
return hr;
}
