C++ (Cpp) CValue::isValid示例

	Ptr<ISubtitlesItem> CPangoCairoRenderer::render(Ptr<ISubtitlesItem> i_item)
	{
		Ptr<CSubtitlesTextItem> text = i_item;

		if (text.isNull() || i_item->getType() != SUBTITLES_TYPE_TEXT)
		{
			return Ptr<ISubtitlesItem>();
		}

		Ptr<CCairoSurface> surface = new CCairoSurface(m_displaySize.Height, m_displaySize.Width, SURFACE_FORMAT_ARGB32);

		cairo_t * cairo = cairo_create(surface->getSurface());
		
		cairo_set_source_rgba(cairo, 0.0, 0.0, 0.0, 0.0);
		cairo_paint(cairo);
		
		PangoLayout * layout = pango_cairo_create_layout(cairo);

		pango_layout_set_width(layout, m_displaySize.Width*PANGO_SCALE);
		pango_layout_set_wrap(layout, PANGO_WRAP_WORD);
		pango_layout_set_alignment(layout, PANGO_ALIGN_CENTER);
		pango_layout_set_text(layout, text->getText().c_str(), -1);

		PangoFontDescription * font = pango_font_description_from_string(m_font.c_str());
		pango_layout_set_font_description(layout, font);
		pango_font_description_free(font);

		cairo_set_source_rgb(cairo, 1.0, 1.0, 1.0);

		pango_cairo_update_layout(cairo, layout);
		pango_cairo_show_layout(cairo, layout);

		CValue<CRectangle> rect = getPixelRectangle(layout);
		
		cairo_destroy(cairo);

		g_object_unref(layout);

		if (rect.isValid())
		{

			Ptr<CCairoSurface> textSurface = new CCairoSurface(*surface, rect.getValue()); 
			
			CSize size = rect.getValue().Size;
			CPoint position = computePosition(size);
			CRectangle newRect(position, size);
			
			return new CSubtitlesGraphicsItem(textSurface, newRect, text->getBeginTime(), text->getEndTime());
		}

		return Ptr<ISubtitlesItem>();
	}