#include <decompressed_image.h>

Public Types
enum class	Format { kInvalid , kGrey , kGreyAlpha , kRGB , kRGBA }

Public Member Functions
	DecompressedImage ()

	DecompressedImage (ISize size, Format format, std::shared_ptr< const fml::Mapping > allocation)

	~DecompressedImage ()

const ISize &	GetSize () const

bool	IsValid () const

Format	GetFormat () const

const std::shared_ptr< const fml::Mapping > &	GetAllocation () const

DecompressedImage	ConvertToRGBA () const

Detailed Description

Definition at line 15 of file decompressed_image.h.

Member Enumeration Documentation

◆ Format

enum impeller::DecompressedImage::Format

strong

Enumerator
kInvalid
kGrey
kGreyAlpha
kRGB
kRGBA

Definition at line 17 of file decompressed_image.h.

                     {
     kInvalid,
     kGrey,
     kGreyAlpha,
     kRGB,
     kRGBA,
   };

Constructor & Destructor Documentation

◆ DecompressedImage() [1/2]

impeller::DecompressedImage::DecompressedImage ( )

default

◆ DecompressedImage() [2/2]

impeller::DecompressedImage::DecompressedImage	(	ISize	size,
		Format	format,
		std::shared_ptr< const fml::Mapping >	allocation
	)

Definition at line 16 of file decompressed_image.cc.

     : size_(size), format_(format), allocation_(std::move(allocation)) {
   if (!allocation_ || size.IsEmpty() || format_ == Format::kInvalid) {
     return;
   }
   is_valid_ = true;
 }

◆ ~DecompressedImage()

impeller::DecompressedImage::~DecompressedImage ( )

default

Member Function Documentation

◆ ConvertToRGBA()

DecompressedImage impeller::DecompressedImage::ConvertToRGBA ( ) const

Definition at line 62 of file decompressed_image.cc.

                                                          {
   if (!is_valid_) {
     return {};
   }
  
   if (format_ == Format::kRGBA) {
     return DecompressedImage{size_, format_, allocation_};
   }
  
   const auto bpp = GetBytesPerPixel(format_);
   const auto source_byte_size = size_.Area() * bpp;
   if (allocation_->GetSize() < source_byte_size) {
     return {};
   }
  
   auto rgba_allocation = std::make_shared<Allocation>();
   if (!rgba_allocation->Truncate(Bytes{size_.Area() * 4u}, false)) {
     return {};
   }
  
   const uint8_t* source = allocation_->GetMapping();
   uint8_t* dest = rgba_allocation->GetBuffer();
  
   for (size_t i = 0, j = 0; i < source_byte_size; i += bpp, j += 4u) {
     switch (format_) {
       case DecompressedImage::Format::kGrey:
         dest[j + 0] = source[i];
         dest[j + 1] = source[i];
         dest[j + 2] = source[i];
         dest[j + 3] = std::numeric_limits<uint8_t>::max();
         break;
       case DecompressedImage::Format::kGreyAlpha:
         dest[j + 0] = std::numeric_limits<uint8_t>::max();
         dest[j + 1] = std::numeric_limits<uint8_t>::max();
         dest[j + 2] = std::numeric_limits<uint8_t>::max();
         dest[j + 3] = source[i];
         break;
       case DecompressedImage::Format::kRGB:
         dest[j + 0] = source[i + 0];
         dest[j + 1] = source[i + 1];
         dest[j + 2] = source[i + 2];
         dest[j + 3] = std::numeric_limits<uint8_t>::max();
         break;
       case DecompressedImage::Format::kInvalid:
       case DecompressedImage::Format::kRGBA:
         // Should never happen. The necessary checks have already been
         // performed.
         FML_CHECK(false);
         break;
     }
   }
  
   return DecompressedImage{
       size_, Format::kRGBA,
       std::make_shared<fml::NonOwnedMapping>(
           rgba_allocation->GetBuffer(),                //
           rgba_allocation->GetLength().GetByteSize(),  //
           [rgba_allocation](auto, auto) {})            //
   };
 }

References impeller::TSize< T >::Area(), impeller::GetBytesPerPixel(), kGrey, kGreyAlpha, kInvalid, kRGB, and kRGBA.

◆ GetAllocation()

const std::shared_ptr< const fml::Mapping > & impeller::DecompressedImage::GetAllocation ( ) const

Definition at line 41 of file decompressed_image.cc.

           {
   return allocation_;
 }

Referenced by impeller::CreateTextureForDecompressedImage().

◆ GetFormat()

DecompressedImage::Format impeller::DecompressedImage::GetFormat ( ) const

Definition at line 37 of file decompressed_image.cc.

                                                            {
   return format_;
 }

◆ GetSize()

const ISize & impeller::DecompressedImage::GetSize ( ) const

Definition at line 33 of file decompressed_image.cc.

                                               {
   return size_;
 }