[DirectWrite] How to create IDWriteFontFileEnumerator from SystemFontCollection?

Question

[DirectWrite] How to create IDWriteFontFileEnumerator from SystemFontCollection?

Bergeron, Jérémie 61

Is there a way to create a IDWriteFontFileEnumerator from the IDWriteFactory::GetSystemFontCollection?

From what I can see, I can create an IDWriteFontFileEnumerator from IDWriteFontCollectionLoader::CreateEnumeratorFromKey, but since I don't know the key and keySize of IDWriteFontCollection created by IDWriteFactory::GetSystemFontCollection , I don't see how I can use IDWriteFontFileEnumerator.

Does IDWriteFontFileEnumerator only works with custom collection?

Jeanine Zhang-MSFT 11,356 Reputation points Microsoft External Staff

2023-10-10T02:47:46.6766667+00:00

I suggest you could try to create an IDWriteFontFileEnumerator object by using the IDWriteFactory::CreateCustomFontCollection`.

You could refer to the Doc:Custom Font Collections (Windows 7/8)

Newer APIs were added in Windows 10 and again in the Windows 10 Creators Update (preview build 15021 or later) that make it easier to implement several of the scenarios mentioned.

If you want to use fonts that are included as part of Windows 10 but that are not currently installed on the current system. Such fonts can be accessed from the Windows font service by using the GetSystemFontSet method, or by calling IDWriteFactory3::GetSystemFontCollection with includeDownloadableFonts set to TRUE.

For more details, you could refer to the Doc:Custom Font Sets
Bergeron, Jérémie 61 Reputation points

2023-10-10T12:59:50.45+00:00

Hi,
My final goal is to get all the system fonts filename. With IDWriteFontFileEnumerator, I think I could get all the system fonts filename.

I don't see how an Custom Font Collections (Windows 7/8) or an Custom Font Sets would help me since these are not the system font.
Jeanine Zhang-MSFT 11,356 Reputation points Microsoft External Staff

2023-10-19T06:10:34.9266667+00:00

Have you got any updates about this issue? Could you please check Castorix31's answer?

1 answer

Your answer

Jeanine Zhang-MSFT 11,356 Reputation points Microsoft External Staff

2023-10-10T02:47:46.6766667+00:00

I suggest you could try to create an IDWriteFontFileEnumerator object by using the IDWriteFactory::CreateCustomFontCollection`.

You could refer to the Doc:Custom Font Collections (Windows 7/8)

Newer APIs were added in Windows 10 and again in the Windows 10 Creators Update (preview build 15021 or later) that make it easier to implement several of the scenarios mentioned.

If you want to use fonts that are included as part of Windows 10 but that are not currently installed on the current system. Such fonts can be accessed from the Windows font service by using the GetSystemFontSet method, or by calling IDWriteFactory3::GetSystemFontCollection with includeDownloadableFonts set to TRUE.

For more details, you could refer to the Doc:Custom Font Sets
Bergeron, Jérémie 61 Reputation points

2023-10-10T12:59:50.45+00:00

Hi,
My final goal is to get all the system fonts filename. With IDWriteFontFileEnumerator, I think I could get all the system fonts filename.

I don't see how an Custom Font Collections (Windows 7/8) or an Custom Font Sets would help me since these are not the system font.
Jeanine Zhang-MSFT 11,356 Reputation points Microsoft External Staff

2023-10-19T06:10:34.9266667+00:00

Have you got any updates about this issue? Could you please check Castorix31's answer?

Answer 1

Castorix31 91,876

You can do :

IDWriteFactory3::GetSystemFontSet

loop on IDWriteFontSet::GetFontCount

IDWriteFontSet::GetFontFaceReference

IDWriteFontFaceReference::GetFontFile

IDWriteFontFile::GetLoader

IDWriteFontFileLoader::QueryInterface to get IDWriteLocalFontFileLoader

IDWriteFontFile::GetReferenceKey

then

IDWriteLocalFontFileLoader::GetFilePathFromKey

Bergeron, Jérémie 61 Reputation points

2023-10-10T17:45:41.32+00:00

This is exactly what I am currently doing !

But, this works only for Windows 10 or above.

I found another way for windows 7 or above, but it does so many calls that it can take like maximum 10 seconds to process:

IDWriteFactory::GetSystemFontCollection

IDWriteFontCollection::GetFontFamilyCount

IDWriteFontCollection::GetFontFamily

IDWriteFontFamily::GetFontCount

IDWriteFontFamily::GetFont

IDWriteFont::CreateFontFace

IDWriteFontFace::GetFiles

IDWriteFontFile::GetLoader

IDWriteFontFileLoader::QueryInterface to get IDWriteLocalFontFileLoader

IDWriteFontFile::GetReferenceKey

then

IDWriteLocalFontFileLoader::GetFilePathFromKey

I thought IDWriteFontFileEnumerator could have better performance than doing that.
Castorix31 91,876 Reputation points

2023-10-10T20:25:17.39+00:00

I had also tested a way with the Shell (Get the Font file name Path as shown in File Explorer)

(in C#, nearly same code in C++ (inside button1_Click), but I'm not sure if it was fast...)

Bergeron, Jérémie 61

I have tried to replicate your solution in c++, but I couldn't understand how your query IShellFolder2::GetDetailsEx to obtain the filename.

I don't understand how I can replicate your PKEY_Fonts_Type in c++. Do you know how I can?

Here is my current code:

#include <iostream>
#include <shobjidl_core.h>
#include <shlobj_core.h>


using namespace std;

int main() {

    IShellFolder* psfDesktop;
    HRESULT hr = SHGetDesktopFolder(&psfDesktop);
    LPITEMIDLIST pidlFonts;
    hr = SHGetKnownFolderIDList(FOLDERID_Fonts, 0, NULL, &pidlFonts);
    if (FAILED(hr))
    {
        wcout << L"Fail SHGetKnownFolderIDList" << endl;
    }

    void* ObjpsfFonts;
    hr = psfDesktop->BindToObject(pidlFonts, NULL, __uuidof(IShellFolder), &ObjpsfFonts);
    if (FAILED(hr))
    {
        wcout << L"Fail BindToObject" << endl;
    }

    IEnumIDList* ppenum;
    IShellFolder* psfFonts;
    hr = static_cast<IUnknown*>(ObjpsfFonts)->QueryInterface(__uuidof(IShellFolder), (void**)&psfFonts);
    if (FAILED(hr))
    {
        wcout << L"Fail Cast" << endl;
    }


    hr = psfFonts->EnumObjects(NULL, SHCONTF_ENABLE_ASYNC | SHCONTF_FLATLIST | SHCONTF_FOLDERS | SHCONTF_INCLUDEHIDDEN | SHCONTF_NONFOLDERS, &ppenum);
    if (FAILED(hr))
    {
        wcout << L"Fail EnumObjects" << endl;
    }


    while (1) {
        ULONG celtFetched = 0;
        LPITEMIDLIST pidlChild;

        hr = ppenum->Next(1, &pidlChild, &celtFetched);
        if (FAILED(hr))
        {
            wcout << L"Fail Next" << endl;
        }

        if (celtFetched != 1) {
            break;
        }

        IShellFolder2* psf2Fonts;
        hr = psfFonts->QueryInterface(__uuidof(IShellFolder2), (void**)&psf2Fonts);
        if (FAILED(hr))
        {
            wcout << L"Fail psf2Fonts cast" << endl;
        }

        SHCOLUMNID pkFontsFileNames;
        hr = psf2Fonts->MapColumnToSCID(0, &pkFontsFileNames);
        if (FAILED(hr))
        {
            wcout << L"Fail MapColumnToSCID" << endl;

            continue;
        }

        VARIANT vVariantFontsFilenames;
        hr = psf2Fonts->GetDetailsEx(pidlChild, &pkFontsFileNames, &vVariantFontsFilenames);
        if (FAILED(hr))
        {
            wcout << L"Fail GetDetailsEx" << endl;
            continue;
        }

        if (vVariantFontsFilenames.vt == VT_BSTR) {
            wcout << L"bstrVal=" << vVariantFontsFilenames.bstrVal << endl;
            wcout << endl;
        }
        else
        {
            wcout << L"Error, vVariantFontsFilenames is not a string" << endl;
            wcout << endl;
        }
    }
    return 0;
}

Castorix31 91,876

I converted the C# sample into C++ :


#include <windows.h>
#include <shlobj.h>
#include <shlwapi.h> // StrRetToBuf
#pragma comment (lib, "Shlwapi")

#include <propvarutil.h> // VariantToString
#pragma comment (lib, "Propsys")

#include <iostream>

DEFINE_PROPERTYKEY(PKEY_Fonts_Type, 0x4530d076, 0xb598, 0x4a81, 0x88, 0x13, 0x9b, 0x11, 0x28, 0x6e, 0xf6, 0xea, 5);
DEFINE_PROPERTYKEY(PKEY_Fonts_FileNames, 0x4530d076, 0xb598, 0x4a81, 0x88, 0x13, 0x9b, 0x11, 0x28, 0x6e, 0xf6, 0xea, 7);

int main()
{
    //std::cout << "Hello World!\n";
	HRESULT hr = CoInitialize(NULL);
	IShellFolder* psfFonts = NULL;
	IShellFolder* psfDesktop;
	hr = SHGetDesktopFolder(&psfDesktop);
	PIDLIST_ABSOLUTE pidlFonts;
	hr = SHGetKnownFolderIDList(FOLDERID_Fonts, 0, NULL, &pidlFonts);
	hr = psfDesktop->BindToObject(pidlFonts, NULL, IID_IShellFolder, (void**)&psfFonts);
	if (SUCCEEDED(hr))
	{
		IEnumIDList* ppenum = NULL;
		LPITEMIDLIST pidlChild = NULL;
		ULONG celtFetched = 0;
		hr = psfFonts->EnumObjects(NULL, SHCONTF_ENABLE_ASYNC | SHCONTF_FLATLIST | SHCONTF_FOLDERS | SHCONTF_INCLUDEHIDDEN | SHCONTF_NONFOLDERS, &ppenum);
		if (SUCCEEDED(hr))
		{
			while (hr = ppenum->Next(1, &pidlChild, &celtFetched) == S_OK && celtFetched == 1)
			{
				// Name
				STRRET strretFolderName;
				TCHAR szFolderName[MAX_PATH] = TEXT("");
				if ((psfFonts->GetDisplayNameOf(pidlChild, SHGDN_INFOLDER, &strretFolderName) == S_OK) &&
					(StrRetToBuf(&strretFolderName, pidlChild, szFolderName, MAX_PATH) == S_OK))
				{
					IShellFolder2* psf2Fonts;
					hr = psfFonts->QueryInterface(IID_PPV_ARGS(&psf2Fonts));
					// Type
					VARIANT varFontsType = { 0 };
					PROPERTYKEY pkFontsType = PKEY_Fonts_Type;
					hr = psf2Fonts->GetDetailsEx(pidlChild, &pkFontsType, &varFontsType);
					TCHAR szFontsType[MAX_PATH];
					hr = VariantToString(varFontsType, szFontsType, MAX_PATH);

					// File Names
					VARIANT varFontsFilenames = { 0 };					
					PROPERTYKEY pkFontsFileNames = PKEY_Fonts_FileNames;
					HRESULT hr = psf2Fonts->GetDetailsEx(pidlChild, &pkFontsFileNames, &varFontsFilenames);
					TCHAR szFontsFileNames[MAX_PATH] = TEXT("See below");
					if (varFontsFilenames.vt != VT_EMPTY)
					{						
						hr = VariantToString(varFontsFilenames, szFontsFileNames, MAX_PATH);
					}

					wprintf(TEXT("Name : %s - Type : %s - File Name : %s\r\n"), szFolderName, szFontsType, szFontsFileNames);
					// Enumerate sub-fonts
					if (varFontsFilenames.vt == VT_EMPTY)
					{
						IShellFolder* psfFontsChilds = NULL;
						hr = psf2Fonts->BindToObject(pidlChild, NULL, IID_IShellFolder, (void**)&psfFontsChilds);
						if (SUCCEEDED(hr))
						{
							IEnumIDList* ppenumChild = NULL;
							hr = psfFontsChilds->EnumObjects(NULL, SHCONTF_ENABLE_ASYNC | SHCONTF_FLATLIST | SHCONTF_FOLDERS | SHCONTF_INCLUDEHIDDEN | SHCONTF_NONFOLDERS, &ppenumChild);
							if (SUCCEEDED(hr))
							{
								LPITEMIDLIST pidlChild2 = NULL;
								ULONG celtFetched2 = 0;
								while (hr = ppenumChild->Next(1, &pidlChild2, &celtFetched2) == S_OK && celtFetched2 == 1)
								{
									// Name
									if ((psfFontsChilds->GetDisplayNameOf(pidlChild2, SHGDN_INFOLDER, &strretFolderName) == S_OK) &&
										(StrRetToBuf(&strretFolderName, pidlChild2, szFolderName, MAX_PATH) == S_OK))
									{
										IShellFolder2* psf2FontsChild;
										hr = psfFontsChilds->QueryInterface(IID_PPV_ARGS(&psf2FontsChild));

										// File Names
										VARIANT varFontsFilenames = { 0 };
										PROPERTYKEY pkFontsFileNames = PKEY_Fonts_FileNames;
										HRESULT hr = psf2FontsChild->GetDetailsEx(pidlChild2, &pkFontsFileNames, &varFontsFilenames);
										TCHAR szFontsFileNames[MAX_PATH] = TEXT("See below");
										if (varFontsFilenames.vt != VT_EMPTY)
										{
											hr = VariantToString(varFontsFilenames, szFontsFileNames, MAX_PATH);
										}
										wprintf(TEXT("\tName : %s - Type : %s - File Name : %s\r\n"), szFolderName, szFontsType, szFontsFileNames);
									}
								}
								ppenumChild->Release();
							}
							psfFontsChilds->Release();
						}						
					}	
				}				
			}
			ppenum->Release();
		}
		psfFonts->Release();
	}
	psfDesktop->Release();
	CoUninitialize();
}

Bergeron, Jérémie 61 Reputation points

2023-10-23T23:32:23.3266667+00:00

Thank you. Unfortunately, it is even slower than the two alternatives we discussed

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[DirectWrite] How to create IDWriteFontFileEnumerator from SystemFontCollection?

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