Re: [ft-devel] Updates for gf driver.

[Parth Wazurkar]

[commit f7a27bf38847b4531164f042088535604d3cd2ec]

> I am attaching the example program I am using for checking output,
> its the same `example1.c' program but with some slight modifications
> to see the num_glyphs allocated.

Some comments.

* Your `ftexample.c' can't work correctly.  In function `draw_bitmap'
  there is the following comment:

    /* for simplicity, we assume that `bitmap->pixel_mode' */
    /* is `FT_PIXEL_MODE_GRAY' (i.e., not a bitmap font)   */

  Surprise, surprise!  GF *is* a bitmap font, where
  `bitmap->pixel_mode' is FT_PIXEL_MODE_MONO...

  In other words, you have to adapt both `draw_bitmap' and
  `show_image' to handle the mono format, having 1bit per pixel.

  Honestly spoken, it's kind of disappointing that you completely
  ignored this comment while modifying `ftexample.c'.

Uh Oh, Really sorry, It was an oversight.

* Irrespective of that, there are big memory leaks.  Calling

    FT2_DEBUG=any:7 \
    valgrind --leak-check=full \
      ./ftexample cmr10.600gf 0 \
      2> ftexample.log

  gives the attached log (using a `make devel; make' compilation).

I think this is because of the `gf_free_font' function which certainly has,
some problems I am working on a patch, and will work it out soon.
 

* The next peculiarity is the size of the created bitmap.  I'm not
  sure what glyph gets displayed at index 48 (the charcode value of
  `0' as used in the command above), but the height of the resulting
  bitmap size, 4x7, looks far too small.

Ok. I'll check this.

* Showing `bitmap' at begin of `draw_bitmap' with the debugger, I see

    (gdb) p *bitmap
    $1 = {
      rows = 7,
      width = 4,
      pitch = 5,
      buffer = 0x76f440 "",
      num_grays = 0,
      pixel_mode = 1 '\001',
      palette_mode = 0 '\000',
      palette = 0x0
    }

  which is also strange: A pitch of 5 implies at least a width of

    4 * 8 + 1 = 33

  pixels (since we have 8 pixels per byte).  However, `width' has
  value 4...

 

I'll fix this.

* If I display the 7 rows bit-wise, I get this:

    0000000000000011111110000000000000000000
    0000000000011111111111110000000000000000
    0000000001111110000011111100000000000000
    0000000011111000000000111110000000000000
    0000001111100000000000001111100000000000
    0000001111000000000000000111100000000000
    0000011111000000000000000111110000000000

  Whatever this is, it looks cut off.

I don't know how to display such bit-wise rows, can you please

share the code for this?

Please fix these issues ASAP!

Yes! I will :-)

Thank you

Parth