Re: Initial pen position in freetype?

[Andrew Tomazos]

On Tue, Jul 21, 2020 at 5:48 PM Andrew Tomazos <andrewtomazos@gmail.com>
wrote:

> On Tue, Jul 21, 2020 at 9:59 AM Lawrence D'Oliveiro <
> ldo@geek-central.gen.nz> wrote:
>
>> On Mon, 20 Jul 2020 19:22:01 +1000, Andrew Tomazos wrote:
>>
>> > What I mean by "pen" is the FT_Vector translation vector that is
>> > passed to FT_Set_Transform before each call to FT_Load_Glyph as each
>> > glyph is rendered.
>>
>> That’s not meant to be used as a “pen”.
>>
>
> In FreeType Glyph Conventions / V it says:
>
> <quote>
> Writing simple text strings
>
> 1. Convert the character string into a series of glyph indices.
> 2. Place the pen to the cursor position.
> 3. Get or load the glyph image.
>
> *4. Translate the glyph so that its ‘origin’ matches the pen position.*5.
> Render the glyph to the target device.
> 6. Increment the pen position by the glyph's advance width (in pixels).
> 7. Start over at step 3 for each of the remaining glyphs.
> 8. When all glyphs are done, set the text cursor to the new pen position.
> </quote>
>
> I believe my use of the term "pen" is the same as in the freetype
> documentation, no?  And I thought that FT_Set_Transform is what is intended
> to implement step 4.  Is that not correct?  If not, then how is step 4
> supposed to be implemented?  And why is FT_Set_Transform unsuitable?
>

And also, using FT_Set_Transform and calling the mentioned variable `pen`
is exactly what the example given in the freetype tutorial does:

    https://www.freetype.org/freetype2/docs/tutorial/example1.c

So can you please clarify your statement.  What is not meant to be used as
what exactly?