gecko-dev/gfx/layers/composite/ImageLayerComposite.cpp

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 "ImageLayerComposite.h"
#include "CompositableHost.h"            // for CompositableHost
#include "Layers.h"                      // for WriteSnapshotToDumpFile, etc
#include "gfx2DGlue.h"                   // for ToFilter
#include "gfxEnv.h"                      // for gfxEnv
#include "gfxRect.h"                     // for gfxRect
#include "mozilla/Assertions.h"          // for MOZ_ASSERT, etc
#include "mozilla/gfx/Matrix.h"          // for Matrix4x4
#include "mozilla/gfx/Point.h"           // for IntSize, Point
#include "mozilla/gfx/Rect.h"            // for Rect
#include "mozilla/layers/Compositor.h"   // for Compositor
#include "mozilla/layers/Effects.h"      // for EffectChain
#include "mozilla/layers/ImageHost.h"    // for ImageHost
#include "mozilla/layers/TextureHost.h"  // for TextureHost, etc
#include "mozilla/mozalloc.h"            // for operator delete
#include "nsAString.h"
#include "mozilla/RefPtr.h"   // for nsRefPtr
#include "nsDebug.h"          // for NS_ASSERTION
#include "nsISupportsImpl.h"  // for MOZ_COUNT_CTOR, etc
#include "nsString.h"         // for nsAutoCString

namespace mozilla {
namespace layers {

using namespace mozilla::gfx;

ImageLayerComposite::ImageLayerComposite(LayerManagerComposite* aManager)
    : ImageLayer(aManager, nullptr),
      LayerComposite(aManager),
      mImageHost(nullptr) {
  MOZ_COUNT_CTOR(ImageLayerComposite);
  mImplData = static_cast<LayerComposite*>(this);
}

ImageLayerComposite::~ImageLayerComposite() {
  MOZ_COUNT_DTOR(ImageLayerComposite);
  MOZ_ASSERT(mDestroyed);

  CleanupResources();
}

bool ImageLayerComposite::SetCompositableHost(CompositableHost* aHost) {
  switch (aHost->GetType()) {
    case CompositableType::IMAGE:
      mImageHost = static_cast<ImageHost*>(aHost);
      return true;
    default:
      return false;
  }
}

void ImageLayerComposite::Disconnect() { Destroy(); }

Layer* ImageLayerComposite::GetLayer() { return this; }

void ImageLayerComposite::SetLayerManager(HostLayerManager* aManager) {
  LayerComposite::SetLayerManager(aManager);
  mManager = aManager;
  if (mImageHost) {
    mImageHost->SetTextureSourceProvider(mCompositor);
  }
}

void ImageLayerComposite::RenderLayer(const IntRect& aClipRect,
                                      const Maybe<gfx::Polygon>& aGeometry) {
  if (!mImageHost || !mImageHost->IsAttached()) {
    return;
  }

#ifdef MOZ_DUMP_PAINTING
  if (gfxEnv::DumpCompositorTextures()) {
    RefPtr<gfx::DataSourceSurface> surf = mImageHost->GetAsSurface();
    if (surf) {
      WriteSnapshotToDumpFile(this, surf);
    }
  }
#endif

  mCompositor->MakeCurrent();

  RenderWithAllMasks(this, mCompositor, aClipRect,
                     [&](EffectChain& effectChain, const IntRect& clipRect) {
                       mImageHost->SetTextureSourceProvider(mCompositor);
                       mImageHost->Composite(mCompositor, this, effectChain,
                                             GetEffectiveOpacity(),
                                             GetEffectiveTransformForBuffer(),
                                             GetSamplingFilter(), clipRect);
                     });
  mImageHost->BumpFlashCounter();
}

void ImageLayerComposite::ComputeEffectiveTransforms(
    const gfx::Matrix4x4& aTransformToSurface) {
  gfx::Matrix4x4 local = GetLocalTransform();

  // Snap image edges to pixel boundaries
  gfxRect sourceRect(0, 0, 0, 0);
  if (mImageHost && mImageHost->IsAttached()) {
    IntSize size = mImageHost->GetImageSize();
    sourceRect.SizeTo(size.width, size.height);
  }
  // Snap our local transform first, and snap the inherited transform as well.
  // This makes our snapping equivalent to what would happen if our content
  // was drawn into a PaintedLayer (gfxContext would snap using the local
  // transform, then we'd snap again when compositing the PaintedLayer).
  mEffectiveTransform = SnapTransform(local, sourceRect, nullptr) *
                        SnapTransformTranslation(aTransformToSurface, nullptr);

  if (mScaleMode != ScaleMode::SCALE_NONE && !sourceRect.IsZeroArea()) {
    NS_ASSERTION(mScaleMode == ScaleMode::STRETCH,
                 "No other scalemodes than stretch and none supported yet.");
    local.PreScale(mScaleToSize.width / sourceRect.Width(),
                   mScaleToSize.height / sourceRect.Height(), 1.0);

    mEffectiveTransformForBuffer =
        SnapTransform(local, sourceRect, nullptr) *
        SnapTransformTranslation(aTransformToSurface, nullptr);
  } else {
    mEffectiveTransformForBuffer = mEffectiveTransform;
  }

  ComputeEffectiveTransformForMaskLayers(aTransformToSurface);
}

bool ImageLayerComposite::IsOpaque() {
  if (!mImageHost || !mImageHost->IsAttached()) {
    return false;
  }

  if (mScaleMode == ScaleMode::STRETCH) {
    return mImageHost->IsOpaque();
  }
  return false;
}

nsIntRegion ImageLayerComposite::GetFullyRenderedRegion() {
  if (!mImageHost || !mImageHost->IsAttached()) {
    return GetShadowVisibleRegion().ToUnknownRegion();
  }

  if (mScaleMode == ScaleMode::STRETCH) {
    nsIntRegion shadowVisibleRegion;
    shadowVisibleRegion.And(GetShadowVisibleRegion().ToUnknownRegion(),
                            nsIntRegion(gfx::IntRect(0, 0, mScaleToSize.width,
                                                     mScaleToSize.height)));
    return shadowVisibleRegion;
  }

  return GetShadowVisibleRegion().ToUnknownRegion();
}

CompositableHost* ImageLayerComposite::GetCompositableHost() {
  if (mImageHost && mImageHost->IsAttached()) {
    return mImageHost.get();
  }

  return nullptr;
}

void ImageLayerComposite::CleanupResources() {
  if (mImageHost) {
    mImageHost->CleanupResources();
    mImageHost->Detach(this);
  }
  mImageHost = nullptr;
}

gfx::SamplingFilter ImageLayerComposite::GetSamplingFilter() {
  return mSamplingFilter;
}

void ImageLayerComposite::GenEffectChain(EffectChain& aEffect) {
  aEffect.mLayerRef = this;
  aEffect.mPrimaryEffect = mImageHost->GenEffect(GetSamplingFilter());
}

void ImageLayerComposite::PrintInfo(std::stringstream& aStream,
                                    const char* aPrefix) {
  ImageLayer::PrintInfo(aStream, aPrefix);
  if (mImageHost && mImageHost->IsAttached()) {
    aStream << "\n";
    nsAutoCString pfx(aPrefix);
    pfx += "  ";
    mImageHost->PrintInfo(aStream, pfx.get());
  }
}

}  // namespace layers
}  // namespace mozilla