DirectWrite space char wrapping - direct2d

Question

First of all sorry for my bad English. But i can't solve my problem for the last few days. I am working on a simple text editor that use DirectWrite to render text. When i render my buffer, that contains a text, direct2d wraps my words, but this doesn't work when i type space chars ' ' or tabs '\t'. My cursor is going outside the editor's window and doesn't "jumt" to the new line.
int RenderSystem::Init(
Settings* set,
HWND hwnd
)
{
if (system_is_init)
return 0;
settings = set;
D2D1CreateFactory(
D2D1_FACTORY_TYPE_SINGLE_THREADED,
&factory
);
DWriteCreateFactory(
DWRITE_FACTORY_TYPE_SHARED,
__uuidof(IDWriteFactory),
(IUnknown**)(&write_factory)
);
LoadFontCollection(L"Fonts/liberation-mono/liberation-mono.ttf");
write_factory->CreateTextFormat(
L"Liberation Mono",
font_collection,
DWRITE_FONT_WEIGHT_REGULAR,
DWRITE_FONT_STYLE_NORMAL,
DWRITE_FONT_STRETCH_NORMAL,
(float)settings->font_size,
L"en-us",
&text_format
);
text_format->SetWordWrapping(
DWRITE_WORD_WRAPPING_WRAP
);
text_renderer = new BasicTextRenderer();
return 0;
}
void RenderSystem::Render(
ID2D1HwndRenderTarget* render_target,
Buffer* buffer
)
{
render_target->CreateSolidColorBrush(
settings->text_foreground_color,
&text_foreground_brush
);
render_target->CreateSolidColorBrush(
settings->cursor_background_color,
&cursor_background_brush
);
render_target->CreateSolidColorBrush(
settings->cursor_foreground_colot,
&cursor_foreground_brush
);
D2D1_SIZE_U render_target_size = render_target->GetPixelSize();
IDWriteTextLayout* text_layout;
UINT size;
WCHAR* text = buffer->GetData(size); //Here i get text from my buffer
write_factory->CreateTextLayout(
text,
size,
text_format,
(float)render_target_size.width,
(float)render_target_size.height,
&text_layout
);
delete[] text;
DrawingContext* drawing_context = new DrawingContext(
render_target,
text_foreground_brush
);
DrawingEffect* cursor_effect = new DrawingEffect(
cursor_foreground_brush,
cursor_background_brush
);
DWRITE_TEXT_RANGE text_range;
text_range.startPosition = buffer->GetCursorPos();
text_range.length = 1;
text_layout->SetDrawingEffect(
cursor_effect,
text_range
);
render_target->BeginDraw();
render_target->Clear(settings->background_color);
text_layout->Draw(
drawing_context,
text_renderer,
0,
0
);
render_target->EndDraw();
text_layout->Release();
text_foreground_brush->Release();
cursor_background_brush->Release();
cursor_foreground_brush->Release();
delete drawing_context;
}
I hope someone will understand what my problem is... Thank you for any help.

Answer 1

I don't think it's necessarily wrong. It's just the way DirectWrite treats trailing spacing characters - they do not contribute to wrapping line width. You can try different wrapping modes, but what you probably need is to implement layout logic yourself, using cluster metrics and line breaking positions from DirectWrite API.
DirectWrite text layout formatting capabilities are enough for general UI text rendering, anything more complicated requires lower level DirectWrite API (text analyzer) and more complicated logic at application side.