Portable PixMap reader/writers for texconv (#180)

Texconv/ExtendedBMP.cpp

@@ -0,0 +1,193 @@
+//--------------------------------------------------------------------------------------
+// File: ExtendedBMP.cpp
+//
+// Utilities for reading BMP files including the DXTn unofficial "FS70"
+// extension created for Microsoft flight simulators.
+//
+// http://www.mwgfx.co.uk/programs/dxtbmp.htm
+//
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+//
+// http://go.microsoft.com/fwlink/?LinkId=248926
+//--------------------------------------------------------------------------------------
+
+#pragma warning(push)
+#pragma warning(disable : 4005)
+#define WIN32_LEAN_AND_MEAN
+#define NOMINMAX
+#define NODRAWTEXT
+#define NOMCX
+#define NOSERVICE
+#define NOHELP
+#pragma warning(pop)
+
+#include <Windows.h>
+
+#include <cstdint>
+#include <memory>
+
+#include "DirectXTex.h"
+
+using namespace DirectX;
+
+namespace
+{
+    struct handle_closer { void operator()(HANDLE h) noexcept { if (h) CloseHandle(h); } };
+
+    using ScopedHandle = std::unique_ptr<void, handle_closer>;
+
+    inline HANDLE safe_handle(HANDLE h) noexcept { return (h == INVALID_HANDLE_VALUE) ? nullptr : h; }
+
+    HRESULT ReadData(_In_z_ const wchar_t* szFile, std::unique_ptr<uint8_t[]>& blob, size_t& blobSize)
+    {
+        blob.reset();
+
+#if (_WIN32_WINNT >= _WIN32_WINNT_WIN8)
+        ScopedHandle hFile(safe_handle(CreateFile2(szFile, GENERIC_READ, FILE_SHARE_READ, OPEN_EXISTING, nullptr)));
+#else
+        ScopedHandle hFile(safe_handle(CreateFileW(szFile, GENERIC_READ, FILE_SHARE_READ, nullptr, OPEN_EXISTING,
+            FILE_FLAG_SEQUENTIAL_SCAN, nullptr)));
+#endif
+        if (!hFile)
+        {
+            return HRESULT_FROM_WIN32(GetLastError());
+        }
+
+        // Get the file size
+        FILE_STANDARD_INFO fileInfo;
+        if (!GetFileInformationByHandleEx(hFile.get(), FileStandardInfo, &fileInfo, sizeof(fileInfo)))
+        {
+            return HRESULT_FROM_WIN32(GetLastError());
+        }
+
+        // File is too big for 32-bit allocation, so reject read (4 GB should be plenty large enough)
+        if (fileInfo.EndOfFile.HighPart > 0)
+        {
+            return HRESULT_FROM_WIN32(ERROR_FILE_TOO_LARGE);
+        }
+
+        // Zero-sized files assumed to be invalid
+        if (fileInfo.EndOfFile.LowPart < 1)
+        {
+            return E_FAIL;
+        }
+
+        // Read file
+        blob.reset(new (std::nothrow) uint8_t[fileInfo.EndOfFile.LowPart]);
+        if (!blob)
+        {
+            return E_OUTOFMEMORY;
+        }
+
+        DWORD bytesRead = 0;
+        if (!ReadFile(hFile.get(), blob.get(), fileInfo.EndOfFile.LowPart, &bytesRead, nullptr))
+        {
+            return HRESULT_FROM_WIN32(GetLastError());
+        }
+
+        if (bytesRead != fileInfo.EndOfFile.LowPart)
+        {
+            return E_FAIL;
+        }
+
+        blobSize = fileInfo.EndOfFile.LowPart;
+
+        return S_OK;
+    }
+
+    HRESULT LoadFromExtendedBMPMemory(
+        _In_reads_bytes_(size) const void* pSource,
+        _In_ size_t size,
+        _Out_opt_ TexMetadata* metadata,
+        _Out_ ScratchImage& image)
+    {
+        // This loads from non-standard BMP files that are not supported by WIC
+        image.Release();
+
+        if (size < (sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER)))
+            return E_FAIL;
+
+        // Valid BMP files always start with 'BM' at the top
+        auto filehdr = reinterpret_cast<const BITMAPFILEHEADER*>(pSource);
+        if (filehdr->bfType != 0x4D42)
+            return E_FAIL;
+
+        if (size < filehdr->bfOffBits)
+            return E_FAIL;
+
+        auto header = reinterpret_cast<const BITMAPINFOHEADER*>(reinterpret_cast<const uint8_t*>(pSource) + sizeof(BITMAPFILEHEADER));
+        if (header->biSize != sizeof(BITMAPINFOHEADER))
+            return E_FAIL;
+
+        if (header->biWidth < 1 || header->biHeight < 1 || header->biPlanes != 1 || header->biBitCount != 16)
+        {
+            return HRESULT_FROM_WIN32(ERROR_NOT_SUPPORTED);
+        }
+
+        DXGI_FORMAT format = DXGI_FORMAT_UNKNOWN;
+        switch (header->biCompression)
+        {
+        case 0x31545844: // FourCC "DXT1"
+            format = DXGI_FORMAT_BC1_UNORM;
+            break;
+        case 0x33545844: // FourCC "DXT3"
+            format = DXGI_FORMAT_BC2_UNORM;
+            break;
+        case 0x35545844: // FourCC "DXT5"
+            format = DXGI_FORMAT_BC3_UNORM;
+            break;
+
+        default:
+            return HRESULT_FROM_WIN32(ERROR_NOT_SUPPORTED);
+        }
+
+        HRESULT hr = image.Initialize2D(format, size_t(header->biWidth), size_t(header->biHeight), 1, 1);
+        if (FAILED(hr))
+            return hr;
+
+        if (header->biSizeImage != image.GetPixelsSize())
+            return E_UNEXPECTED;
+
+        size_t remaining = size - filehdr->bfOffBits;
+        if (!remaining)
+            return E_FAIL;
+
+        if (remaining < image.GetPixelsSize())
+            return E_UNEXPECTED;
+
+        auto pixels = reinterpret_cast<const uint8_t*>(pSource) + filehdr->bfOffBits;
+
+        memcpy(image.GetPixels(), pixels, image.GetPixelsSize());
+
+        if (metadata)
+        {
+            *metadata = image.GetMetadata();
+        }
+
+        return S_OK;
+    }
+}
+
+HRESULT __cdecl LoadFromBMPEx(
+    _In_z_ const wchar_t* szFile,
+    _In_ WIC_FLAGS flags,
+    _Out_opt_ TexMetadata* metadata,
+    _Out_ ScratchImage& image) noexcept
+{
+    std::unique_ptr<uint8_t[]> bmpData;
+    size_t bmpSize;
+    HRESULT hr = ReadData(szFile, bmpData, bmpSize);
+    if (FAILED(hr))
+        return hr;
+
+    hr = LoadFromWICMemory(bmpData.get(), bmpSize, flags, metadata, image);
+    if (FAILED(hr))
+        return hr;
+
+    hr = LoadFromExtendedBMPMemory(bmpData.get(), bmpSize, metadata, image);
+    if (FAILED(hr))
+        return hr;
+
+    return S_OK;
+}