DWriteCore returns shifted glyph indices in a glyph run

[timeester3648]

Describe the bug

I have noticed that some fonts (not all) just give wrong glyph indices when passed to DrawGlyphRun in the DWRITE_GLYPH_RUN. For example when i use FreeType to check the index for space in the AppleStorm font I get the glyph index 1. When i check on FontDrop I also get the index as 1 as shown in the screenshot.

Even when I ask DWriteCore itself to give me the glyph indices using GetGlyphIndices, it tells me space is glyph index 1. But when layed out it gives me 3. This results in situations like this, where with Open Sans it gives the correct result:

but when I switch to the offending font, it shifts it 2 indices to the right:

Steps to reproduce the bug

1. Since i cannot attach font files, 1 font that definitely does not work is the AppleStorm font.
2. Use that file to the retrieve some glyph indices using GetGlyphIndices, like space with codepoint 32.
3. See that it returns glyph index 1 for space.
4. Then layout text and see that the glyph index it has given (in this font) is 3.

Expected behavior

DWriteCore returns the correct glyph indices for the given codepoints. The same it also returns in GetGlyphIndices.

Screenshots

No response

NuGet package version

None

Packaging type

Unpackaged

Windows version

Windows 11 version 22H2 (22621, 2022 Update)

IDE

Visual Studio 2022

Additional context

No response