Files
UnrealEngineUWP/Engine/Source/Developer/ImageWrapper/Private/PngImageWrapper.h
Robert Jones dcc9d7c02e #ttp 309441 - TPS: make sure that libpng allocates memory via engine allocator
#proj Editor.UnrealEd
#branch UE4
#summary libPNG allocations now routing via FMemory correctly
#change Swapped from png_create_read_struct to png_create_read_struct_2 and supplied (wrapped) calls to FMemory::malloc/free

[CL 2068182 by Robert Jones in Main branch]
2014-05-09 11:02:17 -04:00

88 lines
2.1 KiB
C++

// Copyright 1998-2014 Epic Games, Inc. All Rights Reserved.
/*=============================================================================
PngImageWrapper.h: Declares the FPngImageWrapper class.
=============================================================================*/
#pragma once
#if WITH_UNREALPNG
#include "ThirdParty/zlib/zlib-1.2.5/Inc/zlib.h"
#include "ThirdParty/libPNG/libPNG-1.5.2/png.h"
#include "ThirdParty/libPNG/libPNG-1.5.2/pnginfo.h"
/**
* PNG implementation of the helper class
*/
class FPngImageWrapper
: public FImageWrapperBase
{
public:
/**
* Default Constructor.
*/
FPngImageWrapper();
public:
// Begin FImageWrapper Interface
virtual void Compress( int32 Quality ) OVERRIDE;
virtual void Reset( ) OVERRIDE;
virtual bool SetCompressed( const void* InCompressedData, int32 InCompressedSize ) OVERRIDE;
virtual void Uncompress( const ERGBFormat::Type InFormat, int32 InBitDepth ) OVERRIDE;
// End FImageWrapper Interface
/**
* Query whether this is a valid PNG type.
*
* @return true if data a PNG
*/
bool IsPNG() const;
/**
* Load the header information, returns true if successful.
*
* @return true if successful
*/
bool LoadPNGHeader();
/** Helper function used to uncompress PNG data from a buffer */
void UncompressPNGData( const ERGBFormat::Type InFormat, const int32 InBitDepth );
protected:
// Callbacks for the pnglibs
static void user_read_compressed( png_structp png_ptr, png_bytep data, png_size_t length );
static void user_write_compressed( png_structp png_ptr, png_bytep data, png_size_t length );
static void user_flush_data( png_structp png_ptr );
static void user_error_fn( png_structp png_ptr, png_const_charp error_msg );
static void user_warning_fn( png_structp png_ptr, png_const_charp warning_msg );
static void* user_malloc( png_structp png_ptr, png_size_t size);
static void user_free(png_structp png_ptr, png_voidp struct_ptr );
private:
// The read offset into our array.
int32 ReadOffset;
// The color type as defined in the header.
int32 ColorType;
// The number of channels.
uint8 Channels;
};
#endif //WITH_UNREALPNG