impeller::SwapchainTransientsMTL Class Reference

A cache for the onscreen texture attachments used in surface_mtl. More...

#include <swapchain_transients_mtl.h>

Public Member Functions
	SwapchainTransientsMTL (const std::shared_ptr< Allocator > &allocator)
	~SwapchainTransientsMTL ()
void	SetSizeAndFormat (ISize size, PixelFormat format)
	Update the size and pixel format of the onscreens.
std::shared_ptr< Texture >	GetResolveTexture ()
	Retrieve the resolve texture, creating one if needed.
std::shared_ptr< Texture >	GetMSAATexture ()
	Retrieve the MSAA texture, creating one if needed.
std::shared_ptr< Texture >	GetDepthStencilTexture ()
	Retrieve the depth+stencil texture, creating one if needed.

Detailed Description

A cache for the onscreen texture attachments used in surface_mtl.

Typically the onscreen resolve texture is created from a Metal drawable and this cache is only used for the MSAA texture and the depth+stencil attachment. When partial repaint is active, this class also provides a cache for an offscreen resolve texture that is blitted to the real onscreen during present.

Definition at line 25 of file swapchain_transients_mtl.h.

Constructor & Destructor Documentation

SwapchainTransientsMTL()

impeller::SwapchainTransientsMTL::SwapchainTransientsMTL ( const std::shared_ptr< Allocator > &  allocator )

explicit

Definition at line 12 of file swapchain_transients_mtl.mm.

    : allocator_(allocator) {}

~SwapchainTransientsMTL()

impeller::SwapchainTransientsMTL::~SwapchainTransientsMTL ( )

default

Member Function Documentation

GetDepthStencilTexture()

std::shared_ptr< Texture > impeller::SwapchainTransientsMTL::GetDepthStencilTexture

(

)

Retrieve the depth+stencil texture, creating one if needed.

Definition at line 71 of file swapchain_transients_mtl.mm.

                                                                      {
  if (!depth_stencil_tex_) {
    TextureDescriptor desc;
    desc.size = size_;
    desc.sample_count = SampleCount::kCount4;
    desc.format = PixelFormat::kD32FloatS8UInt;
    desc.storage_mode = StorageMode::kDeviceTransient;
    desc.usage = TextureUsage::kRenderTarget;
    desc.type = TextureType::kTexture2DMultisample;
 
    depth_stencil_tex_ = allocator_->CreateTexture(desc);
    if (!depth_stencil_tex_) {
      VALIDATION_LOG << "Failed to allocate depth-stencil texture.";
      return nullptr;
    }
    depth_stencil_tex_->SetLabel("ImpellerOnscreenDepth+Stencil");
  }
 
  return depth_stencil_tex_;
}

References impeller::TextureDescriptor::format, impeller::kCount4, impeller::kD32FloatS8UInt, impeller::kDeviceTransient, impeller::kRenderTarget, impeller::kTexture2DMultisample, impeller::TextureDescriptor::sample_count, impeller::TextureDescriptor::size, impeller::TextureDescriptor::storage_mode, impeller::TextureDescriptor::type, impeller::TextureDescriptor::usage, and VALIDATION_LOG.

GetMSAATexture()

std::shared_ptr< Texture > impeller::SwapchainTransientsMTL::GetMSAATexture

(

)

Retrieve the MSAA texture, creating one if needed.

Definition at line 50 of file swapchain_transients_mtl.mm.

                                                              {
  if (!msaa_tex_) {
    TextureDescriptor desc;
    desc.size = size_;
    desc.sample_count = SampleCount::kCount4;
    desc.format = format_;
    desc.storage_mode = StorageMode::kDeviceTransient;
    desc.usage = TextureUsage::kRenderTarget;
    desc.type = TextureType::kTexture2DMultisample;
 
    msaa_tex_ = allocator_->CreateTexture(desc);
    if (!msaa_tex_) {
      VALIDATION_LOG << "Failed to allocate MSAA texture.";
      return nullptr;
    }
    msaa_tex_->SetLabel("ImpellerOnscreenMSAA");
  }
 
  return msaa_tex_;
}

References impeller::TextureDescriptor::format, impeller::kCount4, impeller::kDeviceTransient, impeller::kRenderTarget, impeller::kTexture2DMultisample, impeller::TextureDescriptor::sample_count, impeller::TextureDescriptor::size, impeller::TextureDescriptor::storage_mode, impeller::TextureDescriptor::type, impeller::TextureDescriptor::usage, and VALIDATION_LOG.

GetResolveTexture()

std::shared_ptr< Texture > impeller::SwapchainTransientsMTL::GetResolveTexture

(

)

Retrieve the resolve texture, creating one if needed.

Definition at line 28 of file swapchain_transients_mtl.mm.

                                                                 {
  if (!resolve_tex_) {
    TextureDescriptor desc;
    desc.size = size_;
    desc.sample_count = SampleCount::kCount1;
    desc.format = format_;
    desc.storage_mode = StorageMode::kDevicePrivate;
    desc.usage = TextureUsage::kShaderRead | TextureUsage::kRenderTarget;
    desc.compression_type = CompressionType::kLossy;
    desc.type = TextureType::kTexture2D;
 
    resolve_tex_ = allocator_->CreateTexture(desc);
    if (!resolve_tex_) {
      VALIDATION_LOG << "Failed to allocate resolve texture.";
      return nullptr;
    }
    resolve_tex_->SetLabel("ImpellerOnscreenResolve");
  }
 
  return resolve_tex_;
}

References impeller::TextureDescriptor::compression_type, impeller::TextureDescriptor::format, impeller::kCount1, impeller::kDevicePrivate, impeller::kLossy, impeller::kRenderTarget, impeller::kShaderRead, impeller::kTexture2D, impeller::TextureDescriptor::sample_count, impeller::TextureDescriptor::size, impeller::TextureDescriptor::storage_mode, impeller::TextureDescriptor::type, impeller::TextureDescriptor::usage, and VALIDATION_LOG.

SetSizeAndFormat()

void impeller::SwapchainTransientsMTL::SetSizeAndFormat	(	ISize	size,
		PixelFormat	format
	)

Update the size and pixel format of the onscreens.

Note: this will invalidate any cached textures if either property changes.

Definition at line 18 of file swapchain_transients_mtl.mm.

                                                                            {
  if (size != size_ || format != format_) {
    resolve_tex_ = nullptr;
    msaa_tex_ = nullptr;
    depth_stencil_tex_ = nullptr;
  }
  size_ = size;
  format_ = format;
}

References format.

---

The documentation for this class was generated from the following files:

• impeller/renderer/backend/metal/swapchain_transients_mtl.h
• impeller/renderer/backend/metal/swapchain_transients_mtl.mm