So I've been working on the Windows part of this (it turns out it was slightly more complex than the functions you highlighted, but that gave me the pointers I needed):

In [1]: __import__('windows_fonts').FontCollection()
Out[1]: <windows_fonts.FontCollection at 0x29a415bdb90>

In [2]: for f in _1:
   ...:     print(repr(f))
   ...:
<FontFamily name="Iosevka Term">
<FontFamily name="Cascadia Code">
<FontFamily name="Cascadia Mono">
<FontFamily name="Arial">
<FontFamily name="Bahnschrift">
<FontFamily name="Calibri">
<FontFamily name="Cambria">
<FontFamily name="Cambria Math">
<FontFamily name="Candara">
<FontFamily name="Comic Sans MS">
<FontFamily name="Consolas">
<FontFamily name="Constantia">
<FontFamily name="Corbel">
<FontFamily name="Courier New">
<FontFamily name="Ebrima">
<FontFamily name="Franklin Gothic">
<FontFamily name="Gabriola">
...
<FontFamily name="Marlett">

In [3]: list(f)
Out[3]:
[<FontVariant family=<FontFamily name="Marlett">, style=Style.NORMAL weight=Weight.MEDIUM>,
 <FontVariant family=<FontFamily name="Marlett">, style=Style.OBLIQUE weight=Weight.MEDIUM>,
 <FontVariant family=<FontFamily name="Marlett">, style=Style.NORMAL weight=Weight.BOLD>,
 <FontVariant family=<FontFamily name="Marlett">, style=Style.OBLIQUE weight=Weight.BOLD>]

In [4]: list(map(lambda f: f.filename, f))
Out[4]:
['C:\\WINDOWS\\FONTS\\MARLETT.TTF',
 'C:\\WINDOWS\\FONTS\\MARLETT.TTF',
 'C:\\WINDOWS\\FONTS\\MARLETT.TTF',
 'C:\\WINDOWS\\FONTS\\MARLETT.TTF']

(I'm planning to release this as a stand-alone python module as I actually need it for a separate project)

it turns out it was slightly more complex than the functions you highlighted, but that gave me the pointers I needed

I am sorry. I thought it was the right logic.
I hope i was in the right direction, so you did not waste too much time on that part.

By curiosity, which method have you used?

• Logic for Windows 10 to this day
  OR
• Logic for Windows Vista to this day

@moi15moi You had the right functions, but the issue was that GetFilePathFromKey needs to be called on an instance of IDWriteLocalFontFileLoader, and unlike most other COM objects where you can just do CoCreateInstance to get one, the only way I've found (from searching) is to get an instance of this is to load a local font file, then ask for it's loader.

And I think I've used the Vista+ approach.

Ok, then, i think you could have called GetLoader from the object you have with GetFiles

Here is the updated version

Logic for Windows Vista to this day:

• GetSystemFontCollection
• Do a for loop with GetFontFamilyCount
  • GetFontFamily
  • GetMatchingFonts - The param weight, stretch, style can be anything. These param seems to only change the order or the return list.
  • Do a for loop with GetFontCount
    • GetFont
    • CreateFontFace
    • GetFiles
    • GetLoader
    • GetReferenceKey
    • GetFilePathFromKey

Here is the pseudo-code

font_collection = GetSystemFontCollection()
 
for i in range(font_collection.GetFontFamilyCount()):
	font_family = font_collection.GetFontFamily(i)
	matching_fonts = GetMatchingFonts(ANY_WEIGHT, ANY_STRETCH, ANY_STYLE)
	
	for j in range(matching_fonts.GetFontCount()):
		font = matching_fonts.GetFont(j)
		font_face = font.CreateFontFace()
		
		files = font_face.GetFiles()
                loader = files.GetLoader()
                reference_key, reference_key_size = files.GetReferenceKey()
		path = loader.GetFilePathFromKey(reference_key, reference_key_size)

Edit: GetLoader return an instance of IDWriteFontFileLoader. It doesn't return of instance of IDWriteLocalFontFileLoader.

Sorry, i missread that.

But, i just found this: https://social.msdn.microsoft.com/Forums/vstudio/en-US/8f57b186-9cf6-417a-8923-092b406d94ea/obtain-filename-from-directwrite-font?forum=windowsuidevelopment

But, i just found this: https://social.msdn.microsoft.com/Forums/vstudio/en-US/8f57b186-9cf6-417a-8923-092b406d94ea/obtain-filename-from-directwrite-font?forum=windowsuidevelopment

Yup, that's what I used to get it working :)

First alpha release available at https://pypi.org/project/windows-fonts/0.1.0a1/ pip install --pre windows-fonts

Hey is anybody working on the mac portion of this? If not I'd like to have a crack.

@kostyafarber, it doesn't look like anyone is working on the mac side of this and in general we have very few people looking into the objective c portion of the code, so I would say go for it! You can also find other mac issues with this label: GUI: MacOSX

For the windows version would we need to write up the code in c++ and write a Python binding and use it in font_manager.py?

For the Mac version are we happy to explore using https://pypi.org/project/pyobjc-framework-CoreText/ or would we prefer to use a binding as well?

I would much rather have bindings in Matplotlib than pick up a dependency for this. If it is so complex that we need a dependency rather than just implementing it, than I think that continuing to search the directories is fine.

I decided to do a repos to show you how I implemented it: https://github.com/moi15moi/FindSystemFontsFilename

I haven't open an PR here since font_manager can search for .afm file which cannot be done with DirectWrite and CoreText (it may be possible with FontConfig, but I haven't check)