[vtkusers] vtkTextSource vtkfont_bits generation

[David Lonie]

To add: vtkTextMapper, vtkTextActor, and vtkTextActor3D all share the
same rendering engine, and support the most functionality (including
non-english characters when supplied with an appropriate font file).
Any other text objects likely do not.

On Fri, Aug 19, 2016 at 8:53 AM, David Lonie <david.lonie at kitware.com> wrote:
> I'm not sure about vtkfont_bits, I've never had to use it before.
>
> And no, vtkVectorText cannot use characters outside of ASCII codepoints 33-126.
>
> vtkTextActor3D can use any characters desired when supplied with a
> vtkTextProperty that has FontFamily=VTK_FONT_FILE and FontFile set to
> a font file with the desired characters. See
> Rendering/FreeType/TestFreeTypeTextMapperNoMath.cxx:
>
>   // UTF-8 freetype handling:
>   vtkNew<vtkTextMapper> mapper10;
>   vtkNew<vtkActor2D> actor10;
>   actor10->SetMapper(mapper10.GetPointer());
>   mapper10->GetTextProperty()->SetFontFile(uncodeFontFile.c_str());
>   mapper10->GetTextProperty()->SetFontFamily(VTK_FONT_FILE);
>   mapper10->GetTextProperty()->SetJustificationToCentered();
>   mapper10->GetTextProperty()->SetVerticalJustificationToCentered();
>   mapper10->GetTextProperty()->SetFontSize(18);
>   mapper10->GetTextProperty()->SetColor(0.0, 1.0, 0.7);
>   mapper10->SetInput("UTF-8 FreeType:
> \xce\xa8\xd2\x94\xd2\x96\xd1\x84\xd2\xbe");
>   actor10->SetPosition(300, 110);
>
> That uses a vtkTextMapper, but the underlying font rendering uses the
> same backend as vtkTextActor3D, and renders the non-english characters
> in the UTF-8 string set via SetInput (see attached).
>
> Dave
>
> On Thu, Aug 18, 2016 at 4:43 PM, Шагит Зиганшин
> <ziganshinshagit at hotmail.com> wrote:
>> And how to use no english characters in vtkVectorText? I'm not sure that
>> vtkVectorText3D can use them.
>>
>>
>> 18 авг. 2016 г. 23:34 пользователь "David Lonie" <david.lonie at kitware.com>
>> написал:
>>>
>>> So, do you or someone knows how to vtkfont_bits?
>>>
>>>
>>> 18 авг. 2016 г. 23:34 пользователь "David Lonie" <david.lonie at kitware.com>
>>> написал:
>>>>
>>>> On Thu, Aug 18, 2016 at 4:29 PM, David Lonie <david.lonie at kitware.com>
>>>> wrote:
>>>> > vtkVectorText only supports a very limited set of fonts and
>>>> > characters. I'm not sure how the polydata it uses was generated.
>>>>
>>>> To elaborate a bit: vtkVectorText does not use the vtkfont_bits, as
>>>> far as I'm aware. See vtkVectorText.cxx -- it contains a large number
>>>> of static arrays containing polygon descriptions of the glyphs. If you
>>>> wish to extend it, you'll need to add more glyphs to this file.