[Devel] Inconsistent use of FT_Set_Pixel_Sizes in winFNT driver

[Huw D M Davies]

Hi,

I'm comparing the use of FT_Set_Pixel_Sizes across bitmap font
formats.  So with pcf, bdf and bitmap only sfnt you should use the
x_ppem and y_ppem members from the available_sizes array as arguments
to FT_Set_Pixel_Sizes.  That seems to make sense.  However with a
winFNT font, the values of x_ppem and y_ppem are known to be
unreliable because in the app850.fon font (and others) the
nominal_point_size value can be bogus.  So to use FT_Set_Pixel_Sizes
on a winFNT you currently need to use the height and width members of
the available sizes array, which is different from any other bitmap
font.

Could I suggest that for winFNT fonts instead of calculating the
x_ppem and y_ppem values from the point size (and hence sometimes
producing a useless value), we simply use the pixel_width and
pixel_height values and then change the test in FNT_Size_Set_Pixels to
compare the available_sizes->y_ppem.  See the attached patch for what
I mean.

Comments?

Thanks,
Huw.

winfnt2.diff
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