UMG - Kerning whilst zooming is terrible on kerned pairs?

Development Programming & Scripting UI
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4

You can’t really merge it because the font cache was re-organised between 4.10 and 4.11 to support shaped text, however you should be able to remake the changes in FFreeTypeInterface::GetKerning (FontCache.cpp).

Replace this:

FT_Error Error = FT_Set_Char_Size( FontFace, 0, InSize*64, FontCacheConstants::HorizontalDPI, FontCacheConstants::VerticalDPI  );

if( InScale != 1.0f )
{
	FT_Matrix ScaleMatrix;
	ScaleMatrix.xy = 0;
	ScaleMatrix.xx = (FT_Fixed)(InScale * 65536);
	ScaleMatrix.yy = (FT_Fixed)(InScale * 65536);
	ScaleMatrix.yx = 0;
	FT_Set_Transform( FontFace, &ScaleMatrix, nullptr );
}
else
{
	FT_Set_Transform( FontFace, nullptr, nullptr );
}

With this:

FT_Error Error = FT_Set_Char_Size( FontFace, 0, InSize*64, FontCacheConstants::HorizontalDPI, FontCacheConstants::VerticalDPI  );
FT_Set_Transform( FontFace, nullptr, nullptr );

Replace this:

// Return pixel sizes
Kerning = KerningVec.x / 64;

With this:

// Return pixel sizes
Kerning = FT_MulFix(KerningVec.x, InScale * 65536) / 64;