C++ (Cpp) IDWriteTextLayout::GetClusterMetrics Examples

Example #1

File: DirectWrite.cpp Project: DBCTRADO/TVTest

int CDirectWriteRenderer::GetFitCharCount(LPCWSTR pText, int Length, int Width, CDirectWriteFont &Font)
{
	if (pText == nullptr || Length == 0)
		return 0;
	if (m_pRenderTarget == nullptr)
		return 0;

	int FitCharCount = 0;

	IDWriteFactory *pFactory = m_System.GetDWriteFactory();

	if (pFactory != nullptr) {
		IDWriteTextFormat *pTextFormat = Font.GetTextFormat();

		if (pTextFormat != nullptr) {
			IDWriteTextLayout *pTextLayout;

			pTextFormat->SetTextAlignment(DWRITE_TEXT_ALIGNMENT_LEADING);
			pTextFormat->SetWordWrapping(DWRITE_WORD_WRAPPING_NO_WRAP);
			if (Length < 0)
				Length = ::lstrlenW(pText);
			HRESULT hr = pFactory->CreateTextLayout(
				pText,
				Length,
				pTextFormat,
				static_cast<float>(Width),
				m_pRenderTarget->GetSize().height,
				&pTextLayout);
			if (SUCCEEDED(hr)) {
				Util::CTempBuffer<DWRITE_CLUSTER_METRICS, 256> ClusterMetrics(Length);
				UINT32 ClusterCount;

				hr = pTextLayout->GetClusterMetrics(ClusterMetrics.GetBuffer(), Length, &ClusterCount);
				if (SUCCEEDED(hr)) {
					float Pos = 0.0f;

					for (UINT32 i = 0; i < ClusterCount; i++) {
						Pos += ClusterMetrics[i].width;
						if (static_cast<int>(std::ceil(Pos)) > Width)
							break;
						FitCharCount += ClusterMetrics[i].length;
					}
				}

				pTextLayout->Release();
			}

			pTextFormat->Release();
		}

		pFactory->Release();
	}

	return FitCharCount;
}