C++ ComPtr::GetMetrics方法代码示例

// Initializes D2D resources used for text rendering.
SampleDebugTextRenderer::SampleDebugTextRenderer(const std::shared_ptr<DX::DeviceResources>& deviceResources) :
Overlay(deviceResources)
{
    ZeroMemory(&m_textMetrics, sizeof(DWRITE_TEXT_METRICS) * XINPUT_MAX_CONTROLLERS);
    ZeroMemory(&m_textMetricsFPS, sizeof(DWRITE_TEXT_METRICS));

    for (unsigned int i = 0; i < 4; i++)
    {
        m_text[i] = L"";
    }
    // Create device-independent resources.
    DX::ThrowIfFailed(
        m_deviceResources->GetDWriteFactory()->CreateTextFormat(
        L"Segoe UI",
        nullptr,
        DWRITE_FONT_WEIGHT_LIGHT,
        DWRITE_FONT_STYLE_NORMAL,
        DWRITE_FONT_STRETCH_NORMAL,
        32.0f,
        L"en-US",
        &m_textFormat
        )
        );

    DX::ThrowIfFailed(
        m_textFormat->SetParagraphAlignment(DWRITE_PARAGRAPH_ALIGNMENT_NEAR)
        );

    DX::ThrowIfFailed(
        m_deviceResources->GetD2DFactory()->CreateDrawingStateBlock(&m_stateBlock)
        );


    // Generate static input text height.
    unsigned int lines = 6; // Increase this if you need to display more than 5 separate action types
    std::wstring inputText = L"";
    for (unsigned int i = 0; i < lines; i++) inputText += L"\n";

    Microsoft::WRL::ComPtr<IDWriteTextLayout> layout;
    DX::ThrowIfFailed(
        m_deviceResources->GetDWriteFactory()->CreateTextLayout(
        inputText.c_str(),
        (uint32) inputText.length(),
        m_textFormat.Get(),
        DEBUG_INPUT_TEXT_MAX_WIDTH,
        DEBUG_INPUT_TEXT_MAX_HEIGHT,
        &layout
        )
        );
    DWRITE_TEXT_METRICS metrics;
    DX::ThrowIfFailed(
        layout->GetMetrics(&metrics)
        );
    m_inputTextHeight = metrics.height;

    CreateDeviceDependentResources();
}

bool CanvasD2D::MeasureTextW(const WCHAR* str, UINT strLen, const TextFormat& format, Gdiplus::RectF& rect)
{
	Microsoft::WRL::ComPtr<IDWriteTextLayout> textLayout;
	HRESULT hr = c_DWFactory->CreateTextLayout(
		str,
		strLen,
		((TextFormatD2D&)format).m_TextFormat.Get(),
		10000,
		10000,
		textLayout.GetAddressOf());
	if (SUCCEEDED(hr))
	{
		DWRITE_TEXT_METRICS metrics;
		textLayout->GetMetrics(&metrics);
		rect.Width = metrics.width + 5.0f;
		rect.Height = metrics.height + 1.0f;  // 1.0f to get same result as GDI+.
		return true;
	}

	return false;
}

DWRITE_TEXT_METRICS TextFormatD2D::GetMetrics(
	const WCHAR* str, UINT strLen, bool gdiEmulation, float maxWidth)
{
	// GDI+ compatibility: If the last character is a newline, GDI+ measurements seem to ignore it.
	bool strippedLastNewLine = false;
	if (strLen > 2 && str[strLen - 1] == L'\n')
	{
		strippedLastNewLine = true;
		--strLen;

		if (str[strLen - 1] == L'\r')
		{
			--strLen;
		}
	}

	DWRITE_TEXT_METRICS metrics = {0};
	Microsoft::WRL::ComPtr<IDWriteTextLayout> textLayout;
	HRESULT hr = CanvasD2D::c_DWFactory->CreateTextLayout(
		str,
		strLen,
		m_TextFormat.Get(),
		maxWidth,
		10000,
		textLayout.GetAddressOf());
	if (SUCCEEDED(hr))
	{
		const float xOffset = m_TextFormat->GetFontSize() / 6.0f;
		if (gdiEmulation)
		{
			Microsoft::WRL::ComPtr<IDWriteTextLayout1> textLayout1;
			textLayout.As(&textLayout1);

			const float emOffset = xOffset / 24.0f;
			const DWRITE_TEXT_RANGE range = {0, strLen};
			textLayout1->SetCharacterSpacing(emOffset, emOffset, 0.0f, range);
		}

		textLayout->GetMetrics(&metrics);
		if (metrics.width > 0.0f)
		{
			if (gdiEmulation)
			{
				metrics.width += xOffset * 2;
				metrics.height += m_ExtraHeight;

				// GDI+ compatibility: If the string contains a newline (even if it is the
				// stripped last character), GDI+ adds the line gap to the overall height.
				if (strippedLastNewLine || wmemchr(str, L'\n', strLen) != nullptr)
				{
					metrics.height += m_LineGap;
				}
			}
			else
			{
				// GDI+ compatibility: With accurate metrics, the line gap needs to be subtracted
				// from the overall height if the string does not contain newlines.
				if (!strippedLastNewLine && wmemchr(str, L'\n', strLen) == nullptr)
				{
					metrics.height -= m_LineGap;
				}
			}
		}
		else
		{
			// GDI+ compatibility: Get rid of the height that DirectWrite assigns to zero-width
			// strings.
			metrics.height = 0.0f;
		}
	}

	return metrics;
}