gecko/gfx/layers/d3d10/LayerManagerD3D10.cpp

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include <algorithm>

#include "LayerManagerD3D10.h"
#include "LayerManagerD3D10Effect.h"
#include "gfxWindowsPlatform.h"
#include "gfx2DGlue.h"
#include "gfxD2DSurface.h"
#include "gfxFailure.h"
#include "cairo-win32.h"
#include "dxgi.h"

#include "ContainerLayerD3D10.h"
#include "ThebesLayerD3D10.h"
#include "ColorLayerD3D10.h"
#include "CanvasLayerD3D10.h"
#include "ReadbackLayerD3D10.h"
#include "ImageLayerD3D10.h"
#include "mozilla/layers/PLayerChild.h"
#include "mozilla/WidgetUtils.h"

#include "../d3d9/Nv3DVUtils.h"

#include "gfxCrashReporterUtils.h"
#include "nsWindowsHelpers.h"
#ifdef MOZ_METRO
#include "DXGI1_2.h"
#endif

namespace mozilla {
namespace layers {

using namespace std;
using namespace mozilla::gfx;

struct Vertex
{
    float position[2];
};

// {592BF306-0EED-4F76-9D03-A0846450F472}
static const GUID sDeviceAttachments = 
{ 0x592bf306, 0xeed, 0x4f76, { 0x9d, 0x3, 0xa0, 0x84, 0x64, 0x50, 0xf4, 0x72 } };
// {716AEDB1-C9C3-4B4D-8332-6F65D44AF6A8}
static const GUID sLayerManagerCount = 
{ 0x716aedb1, 0xc9c3, 0x4b4d, { 0x83, 0x32, 0x6f, 0x65, 0xd4, 0x4a, 0xf6, 0xa8 } };

LayerManagerD3D10::LayerManagerD3D10(nsIWidget *aWidget)
  : mWidget(aWidget)
  , mDisableSequenceForNextFrame(false)
{
}

struct DeviceAttachments
{
  nsRefPtr<ID3D10Effect> mEffect;
  nsRefPtr<ID3D10InputLayout> mInputLayout;
  nsRefPtr<ID3D10Buffer> mVertexBuffer;
  nsRefPtr<ReadbackManagerD3D10> mReadbackManager;
};

LayerManagerD3D10::~LayerManagerD3D10()
{
  if (mDevice) {
    int referenceCount = 0;
    UINT size = sizeof(referenceCount);
    HRESULT hr = mDevice->GetPrivateData(sLayerManagerCount, &size, &referenceCount);
    NS_ASSERTION(SUCCEEDED(hr), "Reference count not found on device.");
    referenceCount--;
    mDevice->SetPrivateData(sLayerManagerCount, sizeof(referenceCount), &referenceCount);

    if (!referenceCount) {
      DeviceAttachments *attachments;
      size = sizeof(attachments);
      mDevice->GetPrivateData(sDeviceAttachments, &size, &attachments);
      // No LayerManagers left for this device. Clear out interfaces stored which
      // hold a reference to the device.
      mDevice->SetPrivateData(sDeviceAttachments, 0, nullptr);

      delete attachments;
    }
  }

  Destroy();
}

static inline void
SetHRESULT(HRESULT* aHresultPtr, HRESULT aHresult)
{
  if (aHresultPtr) {
    *aHresultPtr = aHresult;
  }
}
 
bool
LayerManagerD3D10::Initialize(bool force, HRESULT* aHresultPtr)
{
  ScopedGfxFeatureReporter reporter("D3D10 Layers", force);

  HRESULT hr = E_UNEXPECTED;

  /* Create an Nv3DVUtils instance */
  if (!mNv3DVUtils) {
    mNv3DVUtils = new Nv3DVUtils();
    if (!mNv3DVUtils) {
      NS_WARNING("Could not create a new instance of Nv3DVUtils.\n");
    }
  }

  /* Initialize the Nv3DVUtils object */
  if (mNv3DVUtils) {
    mNv3DVUtils->Initialize();
  }

  mDevice = gfxWindowsPlatform::GetPlatform()->GetD3D10Device();
  if (!mDevice) {
      SetHRESULT(aHresultPtr, hr);
      return false;
  }

  /*
   * Do some post device creation setup
   */
  if (mNv3DVUtils) {
    IUnknown* devUnknown = nullptr;
    if (mDevice) {
      mDevice->QueryInterface(IID_IUnknown, (void **)&devUnknown);
    }
    mNv3DVUtils->SetDeviceInfo(devUnknown);
  }

  int referenceCount = 0;
  UINT size = sizeof(referenceCount);
  // If this isn't there yet it'll fail, count will remain 0, which is correct.
  mDevice->GetPrivateData(sLayerManagerCount, &size, &referenceCount);
  referenceCount++;
  mDevice->SetPrivateData(sLayerManagerCount, sizeof(referenceCount), &referenceCount);

  DeviceAttachments *attachments;
  size = sizeof(DeviceAttachments*);
  if (FAILED(mDevice->GetPrivateData(sDeviceAttachments, &size, &attachments))) {
    attachments = new DeviceAttachments;
    mDevice->SetPrivateData(sDeviceAttachments, sizeof(attachments), &attachments);

    SetLastError(0);
    decltype(D3D10CreateEffectFromMemory)* createEffect =
      (decltype(D3D10CreateEffectFromMemory)*)
        GetProcAddress(LoadLibraryA("d3d10_1.dll"), "D3D10CreateEffectFromMemory");
    if (!createEffect) {
      SetHRESULT(aHresultPtr, HRESULT_FROM_WIN32(GetLastError()));
      return false;
    }

    hr = createEffect((void*)g_main,
                      sizeof(g_main),
                      D3D10_EFFECT_SINGLE_THREADED,
                      mDevice,
                      nullptr,
                      getter_AddRefs(mEffect));
    
    if (FAILED(hr)) {
      SetHRESULT(aHresultPtr, hr);
      return false;
    }

    attachments->mEffect = mEffect;
  
    D3D10_INPUT_ELEMENT_DESC layout[] =
    {
      { "POSITION", 0, DXGI_FORMAT_R32G32_FLOAT, 0, 0, D3D10_INPUT_PER_VERTEX_DATA, 0 },
    };
    D3D10_PASS_DESC passDesc;
    mEffect->GetTechniqueByName("RenderRGBLayerPremul")->GetPassByIndex(0)->
      GetDesc(&passDesc);

    hr = mDevice->CreateInputLayout(layout,
                                    sizeof(layout) / sizeof(D3D10_INPUT_ELEMENT_DESC),
                                    passDesc.pIAInputSignature,
                                    passDesc.IAInputSignatureSize,
                                    getter_AddRefs(mInputLayout));
    
    if (FAILED(hr)) {
      SetHRESULT(aHresultPtr, hr);
      return false;
    }

    attachments->mInputLayout = mInputLayout;
  
    Vertex vertices[] = { {0.0, 0.0}, {1.0, 0.0}, {0.0, 1.0}, {1.0, 1.0} };
    CD3D10_BUFFER_DESC bufferDesc(sizeof(vertices), D3D10_BIND_VERTEX_BUFFER);
    D3D10_SUBRESOURCE_DATA data;
    data.pSysMem = (void*)vertices;

    hr = mDevice->CreateBuffer(&bufferDesc, &data, getter_AddRefs(mVertexBuffer));

    if (FAILED(hr)) {
      SetHRESULT(aHresultPtr, hr);
      return false;
    }

    attachments->mVertexBuffer = mVertexBuffer;
  } else {
    mEffect = attachments->mEffect;
    mVertexBuffer = attachments->mVertexBuffer;
    mInputLayout = attachments->mInputLayout;
  }

  nsRefPtr<IDXGIDevice> dxgiDevice;
  nsRefPtr<IDXGIAdapter> dxgiAdapter;

  mDevice->QueryInterface(dxgiDevice.StartAssignment());
  dxgiDevice->GetAdapter(getter_AddRefs(dxgiAdapter));
  
#ifdef MOZ_METRO
  if (IsRunningInWindowsMetro()) {
    nsRefPtr<IDXGIFactory2> dxgiFactory;
    dxgiAdapter->GetParent(IID_PPV_ARGS(dxgiFactory.StartAssignment()));

    nsIntRect rect;
    mWidget->GetClientBounds(rect);

    DXGI_SWAP_CHAIN_DESC1 swapDesc = { 0 };
    // Automatically detect the width and the height from the winrt CoreWindow
    swapDesc.Width = rect.width;
    swapDesc.Height = rect.height;
    // This is the most common swapchain format
    swapDesc.Format = DXGI_FORMAT_B8G8R8A8_UNORM;
    swapDesc.Stereo = false; 
    // Don't use multi-sampling
    swapDesc.SampleDesc.Count = 1;
    swapDesc.SampleDesc.Quality = 0;
    swapDesc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
    // Use double buffering to enable flip
    swapDesc.BufferCount = 2;
    swapDesc.Scaling = DXGI_SCALING_NONE;
    // All Metro style apps must use this SwapEffect
    swapDesc.SwapEffect = DXGI_SWAP_EFFECT_FLIP_SEQUENTIAL;
    swapDesc.Flags = 0;

    /**
     * Create a swap chain, this swap chain will contain the backbuffer for
     * the window we draw to. The front buffer is the full screen front
     * buffer.
    */
    nsRefPtr<IDXGISwapChain1> swapChain1;
    hr = dxgiFactory->CreateSwapChainForCoreWindow(
           dxgiDevice, (IUnknown *)mWidget->GetNativeData(NS_NATIVE_ICOREWINDOW),
           &swapDesc, nullptr, getter_AddRefs(swapChain1));
    if (FAILED(hr)) {
      SetHRESULT(aHresultPtr, hr);
      return false;
    }
    mSwapChain = swapChain1;
  } else
#endif
  {
    nsRefPtr<IDXGIFactory> dxgiFactory;
    dxgiAdapter->GetParent(IID_PPV_ARGS(dxgiFactory.StartAssignment()));

    DXGI_SWAP_CHAIN_DESC swapDesc;
    ::ZeroMemory(&swapDesc, sizeof(swapDesc));
    swapDesc.BufferDesc.Width = 0;
    swapDesc.BufferDesc.Height = 0;
    swapDesc.BufferDesc.Format = DXGI_FORMAT_B8G8R8A8_UNORM;
    swapDesc.BufferDesc.RefreshRate.Numerator = 60;
    swapDesc.BufferDesc.RefreshRate.Denominator = 1;
    swapDesc.SampleDesc.Count = 1;
    swapDesc.SampleDesc.Quality = 0;
    swapDesc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
    swapDesc.BufferCount = 1;
    swapDesc.OutputWindow = (HWND)mWidget->GetNativeData(NS_NATIVE_WINDOW);
    swapDesc.Windowed = TRUE;
    // We don't really need this flag, however it seems on some NVidia hardware
    // smaller area windows do not present properly without this flag. This flag
    // should have no negative consequences by itself. See bug 613790. This flag
    // is broken on optimus devices. As a temporary solution we don't set it
    // there, the only way of reliably detecting we're on optimus is looking for
    // the DLL. See Bug 623807.
    if (gfxWindowsPlatform::IsOptimus()) {
      swapDesc.Flags = 0;
    } else {
      swapDesc.Flags = DXGI_SWAP_CHAIN_FLAG_GDI_COMPATIBLE;
    }

    /**
     * Create a swap chain, this swap chain will contain the backbuffer for
     * the window we draw to. The front buffer is the full screen front
     * buffer.
    */
    hr = dxgiFactory->CreateSwapChain(dxgiDevice, &swapDesc, getter_AddRefs(mSwapChain));
    if (FAILED(hr)) {
     return false;
    }

    // We need this because we don't want DXGI to respond to Alt+Enter.
    dxgiFactory->MakeWindowAssociation(swapDesc.OutputWindow, DXGI_MWA_NO_WINDOW_CHANGES);
  }

  reporter.SetSuccessful();
  return true;
}

void
LayerManagerD3D10::Destroy()
{
  if (!IsDestroyed()) {
    if (mRoot) {
      static_cast<LayerD3D10*>(mRoot->ImplData())->LayerManagerDestroyed();
    }
    // XXX need to be careful here about surface destruction
    // racing with share-to-chrome message
  }
  LayerManager::Destroy();
}

void
LayerManagerD3D10::SetRoot(Layer *aRoot)
{
  mRoot = aRoot;
}

void
LayerManagerD3D10::BeginTransaction()
{
  mInTransaction = true;

#ifdef MOZ_LAYERS_HAVE_LOG
  MOZ_LAYERS_LOG(("[----- BeginTransaction"));
  Log();
#endif
}

void
LayerManagerD3D10::BeginTransactionWithTarget(gfxContext* aTarget)
{
  mInTransaction = true;
  mTarget = aTarget;
}

bool
LayerManagerD3D10::EndEmptyTransaction(EndTransactionFlags aFlags)
{
  mInTransaction = false;

  if (!mRoot)
    return false;

  EndTransaction(nullptr, nullptr, aFlags);
  return true;
}

void
LayerManagerD3D10::EndTransaction(DrawThebesLayerCallback aCallback,
                                  void* aCallbackData,
                                  EndTransactionFlags aFlags)
{
  mInTransaction = false;

  if (mRoot && !(aFlags & END_NO_IMMEDIATE_REDRAW)) {
    mCurrentCallbackInfo.Callback = aCallback;
    mCurrentCallbackInfo.CallbackData = aCallbackData;

    if (aFlags & END_NO_COMPOSITE) {
      // Apply pending tree updates before recomputing effective
      // properties.
      mRoot->ApplyPendingUpdatesToSubtree();
    }

    // The results of our drawing always go directly into a pixel buffer,
    // so we don't need to pass any global transform here.
    mRoot->ComputeEffectiveTransforms(Matrix4x4());

#ifdef MOZ_LAYERS_HAVE_LOG
    MOZ_LAYERS_LOG(("  ----- (beginning paint)"));
    Log();
#endif

    Render(aFlags);
    mCurrentCallbackInfo.Callback = nullptr;
    mCurrentCallbackInfo.CallbackData = nullptr;
  }

#ifdef MOZ_LAYERS_HAVE_LOG
  Log();
  MOZ_LAYERS_LOG(("]----- EndTransaction"));
#endif

  mTarget = nullptr;
}

already_AddRefed<ThebesLayer>
LayerManagerD3D10::CreateThebesLayer()
{
  nsRefPtr<ThebesLayer> layer = new ThebesLayerD3D10(this);
  return layer.forget();
}

already_AddRefed<ContainerLayer>
LayerManagerD3D10::CreateContainerLayer()
{
  nsRefPtr<ContainerLayer> layer = new ContainerLayerD3D10(this);
  return layer.forget();
}

already_AddRefed<ImageLayer>
LayerManagerD3D10::CreateImageLayer()
{
  nsRefPtr<ImageLayer> layer = new ImageLayerD3D10(this);
  return layer.forget();
}

already_AddRefed<ColorLayer>
LayerManagerD3D10::CreateColorLayer()
{
  nsRefPtr<ColorLayer> layer = new ColorLayerD3D10(this);
  return layer.forget();
}

already_AddRefed<CanvasLayer>
LayerManagerD3D10::CreateCanvasLayer()
{
  nsRefPtr<CanvasLayer> layer = new CanvasLayerD3D10(this);
  return layer.forget();
}

already_AddRefed<ReadbackLayer>
LayerManagerD3D10::CreateReadbackLayer()
{
  nsRefPtr<ReadbackLayer> layer = new ReadbackLayerD3D10(this);
  return layer.forget();
}

TemporaryRef<DrawTarget>
LayerManagerD3D10::CreateOptimalDrawTarget(const IntSize &aSize,
                                           SurfaceFormat aFormat)
{
  if ((aFormat != SurfaceFormat::B8G8R8X8 &&
       aFormat != SurfaceFormat::B8G8R8A8)) {
    return LayerManager::CreateOptimalDrawTarget(aSize, aFormat);
  }

  nsRefPtr<ID3D10Texture2D> texture;
  
  CD3D10_TEXTURE2D_DESC desc(DXGI_FORMAT_B8G8R8A8_UNORM, aSize.width, aSize.height, 1, 1);
  desc.BindFlags = D3D10_BIND_RENDER_TARGET | D3D10_BIND_SHADER_RESOURCE;
  desc.MiscFlags = D3D10_RESOURCE_MISC_GDI_COMPATIBLE;
  
  HRESULT hr = device()->CreateTexture2D(&desc, nullptr, getter_AddRefs(texture));

  if (FAILED(hr)) {
    NS_WARNING("Failed to create new texture for CreateOptimalDrawTarget!");
    return LayerManager::CreateOptimalDrawTarget(aSize, aFormat);
  }

  RefPtr<DrawTarget> dt =
    Factory::CreateDrawTargetForD3D10Texture(texture, aFormat);

  if (!dt) {
    return LayerManager::CreateOptimalDrawTarget(aSize, aFormat);
  }

  return dt;
}


TemporaryRef<DrawTarget>
LayerManagerD3D10::CreateOptimalMaskDrawTarget(const IntSize &aSize)
{
  return CreateOptimalDrawTarget(aSize, SurfaceFormat::B8G8R8A8);
}


TemporaryRef<DrawTarget>
LayerManagerD3D10::CreateDrawTarget(const IntSize &aSize,
                                    SurfaceFormat aFormat)
{
  if ((aFormat != SurfaceFormat::B8G8R8A8 &&
       aFormat != SurfaceFormat::B8G8R8X8) ||
       gfxPlatform::GetPlatform()->GetPreferredCanvasBackend() != BackendType::DIRECT2D) {
    return LayerManager::CreateDrawTarget(aSize, aFormat);
  }

  nsRefPtr<ID3D10Texture2D> texture;
  
  CD3D10_TEXTURE2D_DESC desc(DXGI_FORMAT_B8G8R8A8_UNORM, aSize.width, aSize.height, 1, 1);
  desc.BindFlags = D3D10_BIND_RENDER_TARGET | D3D10_BIND_SHADER_RESOURCE;
  
  HRESULT hr = device()->CreateTexture2D(&desc, nullptr, getter_AddRefs(texture));

  if (FAILED(hr)) {
    NS_WARNING("Failed to create new texture for CreateOptimalDrawTarget!");
    return LayerManager::CreateDrawTarget(aSize, aFormat);
  }

  RefPtr<DrawTarget> surface =
    Factory::CreateDrawTargetForD3D10Texture(texture, aFormat);

  if (!surface) {
    return LayerManager::CreateDrawTarget(aSize, aFormat);
  }
  
  return surface;
}

ReadbackManagerD3D10*
LayerManagerD3D10::readbackManager()
{
  EnsureReadbackManager();
  return mReadbackManager;
}

void
LayerManagerD3D10::SetViewport(const nsIntSize &aViewport)
{
  mViewport = aViewport;

  D3D10_VIEWPORT viewport;
  viewport.MaxDepth = 1.0f;
  viewport.MinDepth = 0;
  viewport.Width = aViewport.width;
  viewport.Height = aViewport.height;
  viewport.TopLeftX = 0;
  viewport.TopLeftY = 0;

  mDevice->RSSetViewports(1, &viewport);

  gfx3DMatrix projection;
  /*
   * Matrix to transform to viewport space ( <-1.0, 1.0> topleft,
   * <1.0, -1.0> bottomright)
   */
  projection._11 = 2.0f / aViewport.width;
  projection._22 = -2.0f / aViewport.height;
  projection._33 = 0.0f;
  projection._41 = -1.0f;
  projection._42 = 1.0f;
  projection._44 = 1.0f;

  HRESULT hr = mEffect->GetVariableByName("mProjection")->
    SetRawValue(&projection._11, 0, 64);

  if (FAILED(hr)) {
    NS_WARNING("Failed to set projection matrix.");
  }
}

void
LayerManagerD3D10::SetupInputAssembler()
{
  mDevice->IASetInputLayout(mInputLayout);

  UINT stride = sizeof(Vertex);
  UINT offset = 0;
  ID3D10Buffer *buffer = mVertexBuffer;
  mDevice->IASetVertexBuffers(0, 1, &buffer, &stride, &offset);
  mDevice->IASetPrimitiveTopology(D3D10_PRIMITIVE_TOPOLOGY_TRIANGLESTRIP);
}

void
LayerManagerD3D10::SetupPipeline()
{
  VerifyBufferSize();
  UpdateRenderTarget();

  nsIntRect rect;
  mWidget->GetClientBounds(rect);

  HRESULT hr;

  hr = mEffect->GetVariableByName("vTextureCoords")->AsVector()->
    SetFloatVector(ShaderConstantRectD3D10(0, 0, 1.0f, 1.0f));

  if (FAILED(hr)) {
    NS_WARNING("Failed to set Texture Coordinates.");
    return;
  }

  ID3D10RenderTargetView *view = mRTView;
  mDevice->OMSetRenderTargets(1, &view, nullptr);

  SetupInputAssembler();

  SetViewport(nsIntSize(rect.width, rect.height));
}

void
LayerManagerD3D10::UpdateRenderTarget()
{
  if (mRTView || !mSwapChain) {
    return;
  }

  HRESULT hr;

  nsRefPtr<ID3D10Texture2D> backBuf;
  hr = mSwapChain->GetBuffer(0, __uuidof(ID3D10Texture2D), (void**)backBuf.StartAssignment());
  if (FAILED(hr)) {
    return;
  }
  mDevice->CreateRenderTargetView(backBuf, nullptr, getter_AddRefs(mRTView));
}

void
LayerManagerD3D10::VerifyBufferSize()
{
  nsIntRect rect;
  mWidget->GetClientBounds(rect);

  if (mSwapChain) {
    DXGI_SWAP_CHAIN_DESC swapDesc;
    mSwapChain->GetDesc(&swapDesc);

    if (swapDesc.BufferDesc.Width == rect.width &&
        swapDesc.BufferDesc.Height == rect.height) {
      return;
    }

    mRTView = nullptr;
    if (IsRunningInWindowsMetro()) {
      mSwapChain->ResizeBuffers(2, rect.width, rect.height,
                                DXGI_FORMAT_B8G8R8A8_UNORM,
                                0);
      mDisableSequenceForNextFrame = true;
    } else if (gfxWindowsPlatform::IsOptimus()) {
      mSwapChain->ResizeBuffers(1, rect.width, rect.height,
                                DXGI_FORMAT_B8G8R8A8_UNORM,
                                0);
    } else {
      mSwapChain->ResizeBuffers(1, rect.width, rect.height,
                                DXGI_FORMAT_B8G8R8A8_UNORM,
                                DXGI_SWAP_CHAIN_FLAG_GDI_COMPATIBLE);
    }
  }
}

void
LayerManagerD3D10::EnsureReadbackManager()
{
  if (mReadbackManager) {
    return;
  }

  DeviceAttachments *attachments;
  UINT size = sizeof(DeviceAttachments*);
  if (FAILED(mDevice->GetPrivateData(sDeviceAttachments, &size, &attachments))) {
    // Strange! This shouldn't happen ... return a readback manager for this
    // layer manager only.
    mReadbackManager = new ReadbackManagerD3D10();
    gfx::LogFailure(NS_LITERAL_CSTRING("Couldn't get device attachments for device."));
    return;
  }

  if (attachments->mReadbackManager) {
    mReadbackManager = attachments->mReadbackManager;
    return;
  }

  mReadbackManager = new ReadbackManagerD3D10();
  attachments->mReadbackManager = mReadbackManager;
}

void
LayerManagerD3D10::Render(EndTransactionFlags aFlags)
{
  static_cast<LayerD3D10*>(mRoot->ImplData())->Validate();

  if (aFlags & END_NO_COMPOSITE) {
    return;
  }

  SetupPipeline();

  float black[] = { 0, 0, 0, 0 };
  device()->ClearRenderTargetView(mRTView, black);

  nsIntRect rect;
  mWidget->GetClientBounds(rect);

  const nsIntRect *clipRect = mRoot->GetClipRect();
  D3D10_RECT r;
  if (clipRect) {
    r.left = (LONG)clipRect->x;
    r.top = (LONG)clipRect->y;
    r.right = (LONG)(clipRect->x + clipRect->width);
    r.bottom = (LONG)(clipRect->y + clipRect->height);
  } else {
    r.left = r.top = 0;
    r.right = rect.width;
    r.bottom = rect.height;
  }
  device()->RSSetScissorRects(1, &r);

  static_cast<LayerD3D10*>(mRoot->ImplData())->RenderLayer();

  if (!mRegionToClear.IsEmpty()) {
    float color[4] = { 0.0f, 0.0f, 0.0f, 0.0f };
    gfx::Matrix4x4 transform;
    effect()->GetVariableByName("mLayerTransform")->SetRawValue(&transform, 0, 64);
    effect()->GetVariableByName("fLayerColor")->AsVector()->SetFloatVector(color);

    ID3D10EffectTechnique *technique = effect()->GetTechniqueByName("RenderClearLayer");

    nsIntRegionRectIterator iter(mRegionToClear);
    const nsIntRect *r;
    while ((r = iter.Next())) {
      effect()->GetVariableByName("vLayerQuad")->AsVector()->SetFloatVector(
        ShaderConstantRectD3D10(
        (float)r->x,
        (float)r->y,
        (float)r->width,
        (float)r->height)
        );

      technique->GetPassByIndex(0)->Apply(0);
      device()->Draw(4, 0);
    }
  }

  // See bug 630197 - we have some reasons to believe if an earlier call
  // returned an error, the upcoming present call may raise an exception.
  // This will check if any of the calls done recently has returned an error
  // and bails on composition. On the -next- frame we will then abandon
  // hardware acceleration from gfxWindowsPlatform::VerifyD2DDevice.
  // This might not be the 'optimal' solution but it will help us assert
  // whether our thoughts of the causes of the issues are correct.
  if (FAILED(mDevice->GetDeviceRemovedReason())) {
    return;
  }

  if (mTarget) {
    PaintToTarget();
  } else {
    mSwapChain->Present(0, mDisableSequenceForNextFrame ? DXGI_PRESENT_DO_NOT_SEQUENCE : 0);
    mDisableSequenceForNextFrame = false;
  }
  RecordFrame();
  PostPresent();
}

void
LayerManagerD3D10::PaintToTarget()
{
  nsRefPtr<ID3D10Texture2D> backBuf;
  
  mSwapChain->GetBuffer(0, __uuidof(ID3D10Texture2D), (void**)backBuf.StartAssignment());

  D3D10_TEXTURE2D_DESC bbDesc;
  backBuf->GetDesc(&bbDesc);

  CD3D10_TEXTURE2D_DESC softDesc(bbDesc.Format, bbDesc.Width, bbDesc.Height);
  softDesc.MipLevels = 1;
  softDesc.CPUAccessFlags = D3D10_CPU_ACCESS_READ;
  softDesc.Usage = D3D10_USAGE_STAGING;
  softDesc.BindFlags = 0;

  nsRefPtr<ID3D10Texture2D> readTexture;

  HRESULT hr = device()->CreateTexture2D(&softDesc, nullptr, getter_AddRefs(readTexture));
  if (FAILED(hr)) {
    ReportFailure(NS_LITERAL_CSTRING("LayerManagerD3D10::PaintToTarget(): Failed to create texture"),
                  hr);
    return;
  }

  device()->CopyResource(readTexture, backBuf);

  D3D10_MAPPED_TEXTURE2D map;
  readTexture->Map(0, D3D10_MAP_READ, 0, &map);

  nsRefPtr<gfxImageSurface> tmpSurface =
    new gfxImageSurface((unsigned char*)map.pData,
                        gfxIntSize(bbDesc.Width, bbDesc.Height),
                        map.RowPitch,
                        gfxImageFormat::ARGB32);

  mTarget->SetSource(tmpSurface);
  mTarget->SetOperator(gfxContext::OPERATOR_OVER);
  mTarget->Paint();

  readTexture->Unmap(0);
}

void
LayerManagerD3D10::ReportFailure(const nsACString &aMsg, HRESULT aCode)
{
  // We could choose to abort here when hr == E_OUTOFMEMORY.
  nsCString msg;
  msg.Append(aMsg);
  msg.AppendLiteral(" Error code: ");
  msg.AppendInt(uint32_t(aCode));
  NS_WARNING(msg.BeginReading());

  gfx::LogFailure(msg);
}

LayerD3D10::LayerD3D10(LayerManagerD3D10 *aManager)
  : mD3DManager(aManager)
{
}

ID3D10EffectTechnique*
LayerD3D10::SelectShader(uint8_t aFlags)
{
  switch (aFlags) {
  case (SHADER_RGBA | SHADER_NON_PREMUL | SHADER_LINEAR | SHADER_MASK):
    return effect()->GetTechniqueByName("RenderRGBALayerNonPremulMask");
  case (SHADER_RGBA | SHADER_NON_PREMUL | SHADER_LINEAR | SHADER_NO_MASK):
    return effect()->GetTechniqueByName("RenderRGBALayerNonPremul");
  case (SHADER_RGBA | SHADER_NON_PREMUL | SHADER_POINT | SHADER_NO_MASK):
    return effect()->GetTechniqueByName("RenderRGBALayerNonPremulPoint");
  case (SHADER_RGBA | SHADER_NON_PREMUL | SHADER_POINT | SHADER_MASK):
    return effect()->GetTechniqueByName("RenderRGBALayerNonPremulPointMask");
  case (SHADER_RGBA | SHADER_PREMUL | SHADER_LINEAR | SHADER_MASK_3D):
    return effect()->GetTechniqueByName("RenderRGBALayerPremulMask3D");
  case (SHADER_RGBA | SHADER_PREMUL | SHADER_LINEAR | SHADER_MASK):
    return effect()->GetTechniqueByName("RenderRGBALayerPremulMask");
  case (SHADER_RGBA | SHADER_PREMUL | SHADER_LINEAR | SHADER_NO_MASK):
    return effect()->GetTechniqueByName("RenderRGBALayerPremul");
  case (SHADER_RGBA | SHADER_PREMUL | SHADER_POINT | SHADER_MASK):
    return effect()->GetTechniqueByName("RenderRGBALayerPremulPointMask");
  case (SHADER_RGBA | SHADER_PREMUL | SHADER_POINT | SHADER_NO_MASK):
    return effect()->GetTechniqueByName("RenderRGBALayerPremulPoint");
  case (SHADER_RGB | SHADER_PREMUL | SHADER_POINT | SHADER_MASK):
    return effect()->GetTechniqueByName("RenderRGBLayerPremulPointMask");
  case (SHADER_RGB | SHADER_PREMUL | SHADER_POINT | SHADER_NO_MASK):
    return effect()->GetTechniqueByName("RenderRGBLayerPremulPoint");
  case (SHADER_RGB | SHADER_PREMUL | SHADER_LINEAR | SHADER_MASK):
    return effect()->GetTechniqueByName("RenderRGBLayerPremulMask");
  case (SHADER_RGB | SHADER_PREMUL | SHADER_LINEAR | SHADER_NO_MASK):
    return effect()->GetTechniqueByName("RenderRGBLayerPremul");
  case (SHADER_SOLID | SHADER_MASK):
    return effect()->GetTechniqueByName("RenderSolidColorLayerMask");
  case (SHADER_SOLID | SHADER_NO_MASK):
    return effect()->GetTechniqueByName("RenderSolidColorLayer");
  case (SHADER_COMPONENT_ALPHA | SHADER_MASK):
    return effect()->GetTechniqueByName("RenderComponentAlphaLayerMask");
  case (SHADER_COMPONENT_ALPHA | SHADER_NO_MASK):
    return effect()->GetTechniqueByName("RenderComponentAlphaLayer");
  case (SHADER_YCBCR | SHADER_MASK):
    return effect()->GetTechniqueByName("RenderYCbCrLayerMask");
  case (SHADER_YCBCR | SHADER_NO_MASK):
    return effect()->GetTechniqueByName("RenderYCbCrLayer");
  default:
    NS_ERROR("Invalid shader.");
    return nullptr;
  }
}

uint8_t
LayerD3D10::LoadMaskTexture()
{
  if (Layer* maskLayer = GetLayer()->GetMaskLayer()) {
    IntSize size;
    nsRefPtr<ID3D10ShaderResourceView> maskSRV =
      static_cast<LayerD3D10*>(maskLayer->ImplData())->GetAsTexture(&size);
  
    if (!maskSRV) {
      return SHADER_NO_MASK;
    }

    Matrix maskTransform;
    Matrix4x4 effectiveTransform = maskLayer->GetEffectiveTransform();
    bool maskIs2D = effectiveTransform.CanDraw2D(&maskTransform);
    NS_ASSERTION(maskIs2D, "How did we end up with a 3D transform here?!");
    Rect bounds = Rect(Point(), Size(size));
    bounds = maskTransform.TransformBounds(bounds);

    effect()->GetVariableByName("vMaskQuad")->AsVector()->SetFloatVector(
      ShaderConstantRectD3D10(
        (float)bounds.x,
        (float)bounds.y,
        (float)bounds.width,
        (float)bounds.height)
      );

    effect()->GetVariableByName("tMask")->AsShaderResource()->SetResource(maskSRV);
    return SHADER_MASK;
  }

  return SHADER_NO_MASK;
}

}
}