bool CDirectWriteRenderer::GetFontMetrics(CDirectWriteFont &Font, FontMetrics *pMetrics)
{
if (pMetrics == nullptr)
return false;
if (m_pRenderTarget == nullptr)
return false;
HRESULT hr = E_UNEXPECTED;
IDWriteTextFormat *pTextFormat = Font.GetTextFormat();
if (pTextFormat != nullptr) {
IDWriteFontCollection *pFontCollection;
hr = pTextFormat->GetFontCollection(&pFontCollection);
if (SUCCEEDED(hr)) {
WCHAR szName[256];
hr = pTextFormat->GetFontFamilyName(szName, lengthof(szName));
if (SUCCEEDED(hr)) {
UINT32 Index;
BOOL fExists;
hr = pFontCollection->FindFamilyName(szName, &Index, &fExists);
if (SUCCEEDED(hr)) {
IDWriteFontFamily *pFontFamily;
hr = pFontCollection->GetFontFamily(Index, &pFontFamily);
if (SUCCEEDED(hr)) {
IDWriteFont *pFont;
hr = pFontFamily->GetFirstMatchingFont(
pTextFormat->GetFontWeight(),
pTextFormat->GetFontStretch(),
pTextFormat->GetFontStyle(),
&pFont);
if (SUCCEEDED(hr)) {
DWRITE_FONT_METRICS Metrics;
pFont->GetMetrics(&Metrics);
const float Ratio = pTextFormat->GetFontSize() / static_cast<float>(Metrics.designUnitsPerEm);
pMetrics->Ascent = Metrics.ascent * Ratio;
pMetrics->Descent = Metrics.descent * Ratio;
pMetrics->LineGap = Metrics.lineGap * Ratio;
pFont->Release();
}
pFontFamily->Release();
}
}
}
}
pFontCollection->Release();
}
return SUCCEEDED(hr);
}
bool IsFamilyInSystemFontCollection(IDWriteFactory* factory, const WCHAR* familyName)
{
bool result = false;
IDWriteFontCollection* systemFontCollection;
HRESULT hr = factory->GetSystemFontCollection(&systemFontCollection);
if (SUCCEEDED(hr))
{
UINT32 familyNameIndex;
BOOL familyNameFound;
HRESULT hr = systemFontCollection->FindFamilyName(
familyName, &familyNameIndex, &familyNameFound);
if (SUCCEEDED(hr) && familyNameFound)
{
result = true;
}
systemFontCollection->Release();
}
return result;
}
int main(void)
{
int argc;
LPWSTR *argv;
WCHAR *fontname, *string;
int len;
HDC dc;
HFONT font, prevfont;
IDWriteFontCollection *sysfc;
UINT32 index;
BOOL exists;
IDWriteFontFamily *dwfamily;
IDWriteFont *dwfont;
IDWriteFontFace *dwface;
featurePreparer *features;
HRESULT hr;
// TODO would using wmain() be adequate?
argv = CommandLineToArgvW(GetCommandLineW(), &argc);
if (argv == NULL)
dieLE("error getting command-line arguments");
if (argc != 3) {
fprintf(stderr, "usage: %ws font string\n", argv[0]);
return 1;
}
fontname = argv[1];
string = argv[2];
len = wcslen(string);
// DirectWrite requires COM
hr = CoInitialize(NULL);
if (hr != S_OK)
die("error initializing COM", hr);
// Uniscribe requires a device context with the font to use
dc = GetDC(NULL);
if (dc == NULL)
dieLE("error getting screen HDC for Uniscribe");
// TODO DEFAULT_CHARSET might affect the results we get
font = CreateFontW(0, 0, 0, 0, 0, FALSE, FALSE, FALSE, DEFAULT_CHARSET, OUT_DEFAULT_PRECIS, CLIP_DEFAULT_PRECIS, DEFAULT_QUALITY, DEFAULT_PITCH | FF_DONTCARE, fontname);
if (font == NULL)
dieLE("error creating font for Uniscribe");
prevfont = (HFONT) SelectObject(dc, font);
if (prevfont == NULL)
dieLE("error selecting font into HDC for Uniscribe");
// and initialize DirectWrite
hr = DWriteCreateFactory(DWRITE_FACTORY_TYPE_SHARED,
__uuidof (IDWriteFactory),
(IUnknown **) (&dwfactory));
if (hr != S_OK)
die("error initializing DirectWrite", hr);
// and load the font *there*
hr = dwfactory->GetSystemFontCollection(&sysfc, TRUE);
if (hr != S_OK)
die("error loading DirectWrite system font collection", hr);
hr = sysfc->FindFamilyName(fontname, &index, &exists);
if (hr != S_OK)
die("error finding DirectWrite font family", hr);
if (!exists)
die("font not found in DirectWrite system font collection", E_FAIL);
hr = sysfc->GetFontFamily(index, &dwfamily);
if (hr != S_OK)
die("error loading DirectWrite font family", hr);
hr = dwfamily->GetFirstMatchingFont(DWRITE_FONT_WEIGHT_NORMAL,
DWRITE_FONT_STRETCH_NORMAL,
DWRITE_FONT_STYLE_NORMAL,
&dwfont);
if (hr != S_OK)
die("error loading DirectWrite font object", hr);
hr = dwfont->CreateFontFace(&dwface);
if (hr != S_OK)
die("error creating DirectWrite font face", hr);
// first, uniscribe only; no features are used
// uniscribeTest(dc, string, len, NULL,
// doScriptItemize, doScriptShape, "Uniscribe");
// next, unprepared features (NULL values)
features = new featurePreparer;
//features->add('z','e','r','o',1);
//features->add('f','r','a','c',1);features->prepare(len);
// uniscribeTest(dc, string, len, features,
// doScriptItemizeOpenType, doScriptShapeOpenType, "Uniscribe OpenType");
directwriteAnalyzerTest(dwface, string, len, features);
delete features;
dwface->Release();
dwfont->Release();
dwfamily->Release();
sysfc->Release();
dwfactory->Release();
SelectObject(dc, prevfont);
DeleteObject(font);
ReleaseDC(NULL, dc);
CoUninitialize();
return 0;
}
