Fixes

src/runtime/text/FontAtlasImageLoader.cpp

@@ -0,0 +1,111 @@
+#include "FontAtlasBuilder.h"
+
+#include <wincodec.h>
+#include <wrl/client.h>
+#include <windows.h>
+
+namespace RenderCadenceCompositor
+{
+namespace
+{
+struct ComThreadGuard
+{
+	~ComThreadGuard()
+	{
+		if (initialized)
+			CoUninitialize();
+	}
+
+	bool Initialize()
+	{
+		const HRESULT result = CoInitializeEx(nullptr, COINIT_MULTITHREADED);
+		initialized = SUCCEEDED(result);
+		return SUCCEEDED(result) || result == RPC_E_CHANGED_MODE;
+	}
+
+	bool initialized = false;
+};
+}
+
+bool FontAtlasBuilder::LoadAtlasImage(FontAtlasBuildOutput& output, std::string& error) const
+{
+	ComThreadGuard comGuard;
+	if (!comGuard.Initialize())
+	{
+		error = "Could not initialize COM for font atlas PNG loading.";
+		return false;
+	}
+
+	Microsoft::WRL::ComPtr<IWICImagingFactory> factory;
+	HRESULT result = CoCreateInstance(
+		CLSID_WICImagingFactory,
+		nullptr,
+		CLSCTX_INPROC_SERVER,
+		IID_PPV_ARGS(factory.GetAddressOf()));
+	if (FAILED(result))
+	{
+		error = "Could not create WIC imaging factory for font atlas PNG loading.";
+		return false;
+	}
+
+	Microsoft::WRL::ComPtr<IWICBitmapDecoder> decoder;
+	result = factory->CreateDecoderFromFilename(
+		output.imagePath.wstring().c_str(),
+		nullptr,
+		GENERIC_READ,
+		WICDecodeMetadataCacheOnLoad,
+		decoder.GetAddressOf());
+	if (FAILED(result))
+	{
+		error = "Could not decode font atlas PNG: " + output.imagePath.string();
+		return false;
+	}
+
+	Microsoft::WRL::ComPtr<IWICBitmapFrameDecode> frame;
+	result = decoder->GetFrame(0, frame.GetAddressOf());
+	if (FAILED(result))
+	{
+		error = "Could not read font atlas PNG frame: " + output.imagePath.string();
+		return false;
+	}
+
+	Microsoft::WRL::ComPtr<IWICFormatConverter> converter;
+	result = factory->CreateFormatConverter(converter.GetAddressOf());
+	if (FAILED(result))
+	{
+		error = "Could not create WIC format converter for font atlas PNG.";
+		return false;
+	}
+
+	result = converter->Initialize(
+		frame.Get(),
+		GUID_WICPixelFormat32bppRGBA,
+		WICBitmapDitherTypeNone,
+		nullptr,
+		0.0,
+		WICBitmapPaletteTypeCustom);
+	if (FAILED(result))
+	{
+		error = "Could not convert font atlas PNG to RGBA.";
+		return false;
+	}
+
+	UINT width = 0;
+	UINT height = 0;
+	converter->GetSize(&width, &height);
+	output.width = static_cast<unsigned>(width);
+	output.height = static_cast<unsigned>(height);
+	output.rgbaPixels.assign(static_cast<std::size_t>(output.width) * output.height * 4u, 0);
+
+	const UINT stride = width * 4u;
+	result = converter->CopyPixels(nullptr, stride, static_cast<UINT>(output.rgbaPixels.size()), output.rgbaPixels.data());
+	if (FAILED(result))
+	{
+		error = "Could not copy font atlas PNG pixels.";
+		return false;
+	}
+
+	error.clear();
+	return true;
+}
+}