C++ ContainerLayer::UseIntermediateSurface方法代码示例

nsIntRect
Layer::CalculateScissorRect(const nsIntRect& aCurrentScissorRect,
                            const gfxMatrix* aWorldTransform)
{
  ContainerLayer* container = GetParent();
  NS_ASSERTION(container, "This can't be called on the root!");

  // Establish initial clip rect: it's either the one passed in, or
  // if the parent has an intermediate surface, it's the extents of that surface.
  nsIntRect currentClip;
  if (container->UseIntermediateSurface()) {
    currentClip.SizeTo(container->GetIntermediateSurfaceRect().Size());
  } else {
    currentClip = aCurrentScissorRect;
  }

  const nsIntRect *clipRect = GetEffectiveClipRect();
  if (!clipRect)
    return currentClip;

  if (clipRect->IsEmpty()) {
    // We might have a non-translation transform in the container so we can't
    // use the code path below.
    return nsIntRect(currentClip.TopLeft(), nsIntSize(0, 0));
  }

  nsIntRect scissor = *clipRect;
  if (!container->UseIntermediateSurface()) {
    gfxMatrix matrix;
    DebugOnly<bool> is2D = container->GetEffectiveTransform().Is2D(&matrix);
    // See DefaultComputeEffectiveTransforms below
    NS_ASSERTION(is2D && matrix.PreservesAxisAlignedRectangles(),
                 "Non preserves axis aligned transform with clipped child should have forced intermediate surface");
    gfxRect r(scissor.x, scissor.y, scissor.width, scissor.height);
    gfxRect trScissor = matrix.TransformBounds(r);
    trScissor.Round();
    if (!gfxUtils::GfxRectToIntRect(trScissor, &scissor)) {
      return nsIntRect(currentClip.TopLeft(), nsIntSize(0, 0));
    }

    // Find the nearest ancestor with an intermediate surface
    do {
      container = container->GetParent();
    } while (container && !container->UseIntermediateSurface());
  }
  if (container) {
    scissor.MoveBy(-container->GetIntermediateSurfaceRect().TopLeft());
  } else if (aWorldTransform) {
    gfxRect r(scissor.x, scissor.y, scissor.width, scissor.height);
    gfxRect trScissor = aWorldTransform->TransformBounds(r);
    trScissor.Round();
    if (!gfxUtils::GfxRectToIntRect(trScissor, &scissor))
      return nsIntRect(currentClip.TopLeft(), nsIntSize(0, 0));
  }
  return currentClip.Intersect(scissor);
}

float
Layer::GetEffectiveOpacity()
{
  float opacity = GetLocalOpacity();
  for (ContainerLayer* c = GetParent(); c && !c->UseIntermediateSurface();
       c = c->GetParent()) {
    opacity *= c->GetLocalOpacity();
  }
  return opacity;
}

CompositionOp
Layer::GetEffectiveMixBlendMode()
{
  if(mMixBlendMode != CompositionOp::OP_OVER)
    return mMixBlendMode;
  for (ContainerLayer* c = GetParent(); c && !c->UseIntermediateSurface();
    c = c->GetParent()) {
    if(c->mMixBlendMode != CompositionOp::OP_OVER)
      return c->mMixBlendMode;
  }

  return mMixBlendMode;
}

gfxContext::GraphicsOperator
Layer::GetEffectiveMixBlendMode()
{
  if(mMixBlendMode != gfxContext::OPERATOR_OVER)
    return mMixBlendMode;
  for (ContainerLayer* c = GetParent(); c && !c->UseIntermediateSurface();
    c = c->GetParent()) {
    if(c->mMixBlendMode != gfxContext::OPERATOR_OVER)
      return c->mMixBlendMode;
  }

  return mMixBlendMode;
}

gfxRect
ThebesLayerComposite::GetDisplayPort()
{
  // We use GetTransform instead of GetEffectiveTransform in this function
  // as we want the transform of the shadowable layers and not that of the
  // shadow layers, which may have been modified due to async scrolling/
  // zooming.
  gfx3DMatrix transform = GetTransform();

  // Find out the area of the nearest display-port to invalidate retained
  // tiles.
  gfxRect displayPort;
  gfxSize parentResolution = GetEffectiveResolution();
  for (ContainerLayer* parent = GetParent(); parent; parent = parent->GetParent()) {
    const FrameMetrics& metrics = parent->GetFrameMetrics();
    if (displayPort.IsEmpty()) {
      if (!metrics.mDisplayPort.IsEmpty()) {
          // We use the bounds to cut down on complication/computation time.
          // This will be incorrect when the transform involves rotation, but
          // it'd be quite hard to retain invalid tiles correctly in this
          // situation anyway.
          displayPort = gfxRect(metrics.mDisplayPort.x,
                                metrics.mDisplayPort.y,
                                metrics.mDisplayPort.width,
                                metrics.mDisplayPort.height);
          displayPort.ScaleRoundOut(parentResolution.width, parentResolution.height);
      }
      parentResolution.width /= metrics.mResolution.scale;
      parentResolution.height /= metrics.mResolution.scale;
    }
    if (parent->UseIntermediateSurface()) {
      transform.PreMultiply(parent->GetTransform());
    }
  }

  // If no display port was found, use the widget size from the layer manager.
  if (displayPort.IsEmpty()) {
    LayerManagerComposite* manager = static_cast<LayerManagerComposite*>(Manager());
    const nsIntSize& widgetSize = manager->GetWidgetSize();
    displayPort.width = widgetSize.width;
    displayPort.height = widgetSize.height;
  }

  // Transform the display port into layer space.
  displayPort = transform.Inverse().TransformBounds(displayPort);

  return displayPort;
}

void
ClientTiledThebesLayer::BeginPaint()
{
  if (ClientManager()->IsRepeatTransaction()) {
    return;
  }

  mPaintData.mLowPrecisionPaintCount = 0;
  mPaintData.mPaintFinished = false;

  // Calculate the transform required to convert screen space into layer space
  mPaintData.mTransformScreenToLayer = GetEffectiveTransform();
  // XXX Not sure if this code for intermediate surfaces is correct.
  //     It rarely gets hit though, and shouldn't have terrible consequences
  //     even if it is wrong.
  for (ContainerLayer* parent = GetParent(); parent; parent = parent->GetParent()) {
    if (parent->UseIntermediateSurface()) {
      mPaintData.mTransformScreenToLayer.PreMultiply(parent->GetEffectiveTransform());
    }
  }
  mPaintData.mTransformScreenToLayer.Invert();

  // Compute the critical display port in layer space.
  mPaintData.mLayerCriticalDisplayPort.SetEmpty();
  const gfx::Rect& criticalDisplayPort = GetParent()->GetFrameMetrics().mCriticalDisplayPort;
  if (!criticalDisplayPort.IsEmpty()) {
    gfxRect transformedCriticalDisplayPort =
      mPaintData.mTransformScreenToLayer.TransformBounds(
        gfxRect(criticalDisplayPort.x, criticalDisplayPort.y,
                criticalDisplayPort.width, criticalDisplayPort.height));
    transformedCriticalDisplayPort.RoundOut();
    mPaintData.mLayerCriticalDisplayPort = nsIntRect(transformedCriticalDisplayPort.x,
                                             transformedCriticalDisplayPort.y,
                                             transformedCriticalDisplayPort.width,
                                             transformedCriticalDisplayPort.height);
  }

  // Calculate the frame resolution.
  mPaintData.mResolution.SizeTo(1, 1);
  for (ContainerLayer* parent = GetParent(); parent; parent = parent->GetParent()) {
    const FrameMetrics& metrics = parent->GetFrameMetrics();
    mPaintData.mResolution.width *= metrics.mResolution.width;
    mPaintData.mResolution.height *= metrics.mResolution.height;
  }

  // Calculate the scroll offset since the last transaction, and the
  // composition bounds.
  mPaintData.mCompositionBounds.SetEmpty();
  mPaintData.mScrollOffset.MoveTo(0, 0);
  Layer* primaryScrollable = ClientManager()->GetPrimaryScrollableLayer();
  if (primaryScrollable) {
    const FrameMetrics& metrics = primaryScrollable->AsContainerLayer()->GetFrameMetrics();
    mPaintData.mScrollOffset = metrics.mScrollOffset;
    gfxRect transformedViewport = mPaintData.mTransformScreenToLayer.TransformBounds(
      gfxRect(metrics.mCompositionBounds.x, metrics.mCompositionBounds.y,
              metrics.mCompositionBounds.width, metrics.mCompositionBounds.height));
    transformedViewport.RoundOut();
    mPaintData.mCompositionBounds =
      nsIntRect(transformedViewport.x, transformedViewport.y,
                transformedViewport.width, transformedViewport.height);
  }
}

/* static */ void
LayerManagerComposite::ComputeRenderIntegrityInternal(Layer* aLayer,
                                                      nsIntRegion& aScreenRegion,
                                                      nsIntRegion& aLowPrecisionScreenRegion,
                                                      const Matrix4x4& aTransform)
{
  if (aLayer->GetOpacity() <= 0.f ||
      (aScreenRegion.IsEmpty() && aLowPrecisionScreenRegion.IsEmpty())) {
    return;
  }

  // If the layer's a container, recurse into all of its children
  ContainerLayer* container = aLayer->AsContainerLayer();
  if (container) {
    // Accumulate the transform of intermediate surfaces
    Matrix4x4 transform = aTransform;
    if (container->UseIntermediateSurface()) {
      transform = aLayer->GetEffectiveTransform();
      transform = aTransform * transform;
    }
    for (Layer* child = aLayer->GetFirstChild(); child;
         child = child->GetNextSibling()) {
      ComputeRenderIntegrityInternal(child, aScreenRegion, aLowPrecisionScreenRegion, transform);
    }
    return;
  }

  // Only painted layers can be incomplete
  PaintedLayer* paintedLayer = aLayer->AsPaintedLayer();
  if (!paintedLayer) {
    return;
  }

  // See if there's any incomplete rendering
  nsIntRegion incompleteRegion = aLayer->GetEffectiveVisibleRegion();
  incompleteRegion.Sub(incompleteRegion, paintedLayer->GetValidRegion());

  if (!incompleteRegion.IsEmpty()) {
    // Calculate the transform to get between screen and layer space
    Matrix4x4 transformToScreen = aLayer->GetEffectiveTransform();
    transformToScreen = aTransform * transformToScreen;

    SubtractTransformedRegion(aScreenRegion, incompleteRegion, transformToScreen);

    // See if there's any incomplete low-precision rendering
    TiledContentHost* composer = nullptr;
    LayerComposite* shadow = aLayer->AsLayerComposite();
    if (shadow) {
      composer = shadow->GetCompositableHost()->AsTiledContentHost();
      if (composer) {
        incompleteRegion.Sub(incompleteRegion, composer->GetValidLowPrecisionRegion());
        if (!incompleteRegion.IsEmpty()) {
          SubtractTransformedRegion(aLowPrecisionScreenRegion, incompleteRegion, transformToScreen);
        }
      }
    }

    // If we can't get a valid low precision region, assume it's the same as
    // the high precision region.
    if (!composer) {
      SubtractTransformedRegion(aLowPrecisionScreenRegion, incompleteRegion, transformToScreen);
    }
  }
}

void
ClientTiledThebesLayer::BeginPaint()
{
  if (ClientManager()->IsRepeatTransaction()) {
    return;
  }

  mPaintData.mLowPrecisionPaintCount = 0;
  mPaintData.mPaintFinished = false;

  // Get the metrics of the nearest scroll container.
  ContainerLayer* scrollParent = nullptr;
  for (ContainerLayer* parent = GetParent(); parent; parent = parent->GetParent()) {
    const FrameMetrics& metrics = parent->GetFrameMetrics();
    if (metrics.mScrollId != FrameMetrics::NULL_SCROLL_ID) {
      scrollParent = parent;
      break;
    }
  }

  if (!scrollParent) {
    // XXX I don't think this can happen, but if it does, warn and set the
    //     composition bounds to empty so that progressive updates are disabled.
    NS_WARNING("Tiled Thebes layer with no scrollable container parent");
    mPaintData.mCompositionBounds.SetEmpty();
    return;
  }

  const FrameMetrics& metrics = scrollParent->GetFrameMetrics();

  // Calculate the transform required to convert screen space into transformed
  // layout device space.
  gfx::Matrix4x4 effectiveTransform = GetEffectiveTransform();
  for (ContainerLayer* parent = GetParent(); parent; parent = parent->GetParent()) {
    if (parent->UseIntermediateSurface()) {
      effectiveTransform = effectiveTransform * parent->GetEffectiveTransform();
    }
  }
  gfx3DMatrix layoutToScreen;
  gfx::To3DMatrix(effectiveTransform, layoutToScreen);
  layoutToScreen.ScalePost(metrics.mCumulativeResolution.scale,
                           metrics.mCumulativeResolution.scale,
                           1.f);

  mPaintData.mTransformScreenToLayout = layoutToScreen.Inverse();

  // Compute the critical display port in layer space.
  mPaintData.mLayoutCriticalDisplayPort.SetEmpty();
  if (!metrics.mCriticalDisplayPort.IsEmpty()) {
    // Convert the display port to screen space first so that we can transform
    // it into layout device space.
    const ScreenRect& criticalDisplayPort = metrics.mCriticalDisplayPort * metrics.mZoom;
    LayoutDeviceRect transformedCriticalDisplayPort =
      ApplyScreenToLayoutTransform(mPaintData.mTransformScreenToLayout, criticalDisplayPort);
    mPaintData.mLayoutCriticalDisplayPort =
      LayoutDeviceIntRect::ToUntyped(RoundedOut(transformedCriticalDisplayPort));
  }

  // Calculate the frame resolution. Because this is Gecko-side, before any
  // async transforms have occurred, we can use mZoom for this.
  mPaintData.mResolution = metrics.mZoom;

  // Calculate the scroll offset since the last transaction, and the
  // composition bounds.
  mPaintData.mCompositionBounds.SetEmpty();
  mPaintData.mScrollOffset.MoveTo(0, 0);
  Layer* primaryScrollable = ClientManager()->GetPrimaryScrollableLayer();
  if (primaryScrollable) {
    const FrameMetrics& metrics = primaryScrollable->AsContainerLayer()->GetFrameMetrics();
    mPaintData.mScrollOffset = metrics.mScrollOffset * metrics.mZoom;
    mPaintData.mCompositionBounds =
      ApplyScreenToLayoutTransform(mPaintData.mTransformScreenToLayout,
                                   ScreenRect(metrics.mCompositionBounds));
  }
}