Re: [ft-devel] rendering differences between 2.2.x, 2.3.x and CVS

[Pierre]

Bonjour David :)

Thanks for your quick reply!

On 4/26/07, David Turner <address@hidden> wrote:
> Bonjour Pierre,
>
> the difference in text height is explained by the fact that, until recently,
> a value of 0 for y_dpi in a call to FT_Set_Char_Size was incorrectly 
> interpreted as
> the default resolution of 72dpi, instead of meaning "same as the horizontal 
> resolution"
>
> this means your code was doing FT_Set_Char_Size(face, size, size, 100, 72) in 
> 2.2.x
> and FT_Set_Char_Size(face, size, size, 100, 100) in 2.3.4 and later

Thanks, I did not notice this change. I updated the example (maybe you
should update the examples in the tutorial part 1&2 as well?) and it
works as expected.

> the Ubuntu version uses the bytecode interpreter, hence the difference with the
> release version of 2.2.1
>
> the 2.3.4 and CVS version should have identical rendering. I think that the 
> image
> shown on the bottom right corner is incorrect, it looks like the one from 16pt 
> instead
> of 20pt

You are right, it is now the correct image.

Having yet a working and simple example, I was finally able to
reproduce the initial bug. A rotated text (axis aligned) have
different sizes.

I added a 96dpi (which is the default in PHP/gd) and a 100dpi:
http://pierre.libgd.org/ft2/96dpi/
http://pierre.libgd.org/ft2/100dpi/

I suppose there is little to do to fix this problem but to increase
the default resolution?

In the worst case, I can simply expose the dpi option (I can't really
change the default one without breaking tons of apps out there).

> Hope this helps,

It definitively does. This kind of details helps me a lot to clean the
libgd code and to significantly improve it (it is quite old...). I
hope I can start to add the new features soon (like what is described
in the ftdiff demo or other new options).

--Pierre