C++ Matrix4x4::ProjectTo2D方法代码示例

void
ContainerLayer::DefaultComputeEffectiveTransforms(const Matrix4x4& aTransformToSurface)
{
  Matrix residual;
  Matrix4x4 idealTransform = GetLocalTransform() * aTransformToSurface;
  idealTransform.ProjectTo2D();
  mEffectiveTransform = SnapTransformTranslation(idealTransform, &residual);

  bool useIntermediateSurface;
  if (GetMaskLayer() ||
      GetForceIsolatedGroup()) {
    useIntermediateSurface = true;
#ifdef MOZ_DUMP_PAINTING
  } else if (gfxUtils::sDumpPainting) {
    useIntermediateSurface = true;
#endif
  } else {
    float opacity = GetEffectiveOpacity();
    CompositionOp blendMode = GetEffectiveMixBlendMode();
    if ((opacity != 1.0f || blendMode != CompositionOp::OP_OVER) && HasMultipleChildren()) {
      useIntermediateSurface = true;
    } else {
      useIntermediateSurface = false;
      gfx::Matrix contTransform;
      if (!mEffectiveTransform.Is2D(&contTransform) ||
#ifdef MOZ_GFX_OPTIMIZE_MOBILE
        !contTransform.PreservesAxisAlignedRectangles()) {
#else
        gfx::ThebesMatrix(contTransform).HasNonIntegerTranslation()) {
#endif
        for (Layer* child = GetFirstChild(); child; child = child->GetNextSibling()) {
          const nsIntRect *clipRect = child->GetEffectiveClipRect();
          /* We can't (easily) forward our transform to children with a non-empty clip
           * rect since it would need to be adjusted for the transform. See
           * the calculations performed by CalculateScissorRect above.
           * Nor for a child with a mask layer.
           */
          if ((clipRect && !clipRect->IsEmpty() && !child->GetVisibleRegion().IsEmpty()) ||
              child->GetMaskLayer()) {
            useIntermediateSurface = true;
            break;
          }
        }
      }
    }
  }

  mUseIntermediateSurface = useIntermediateSurface;
  if (useIntermediateSurface) {
    ComputeEffectiveTransformsForChildren(Matrix4x4::From2D(residual));
  } else {
    ComputeEffectiveTransformsForChildren(idealTransform);
  }

  if (idealTransform.CanDraw2D()) {
    ComputeEffectiveTransformForMaskLayer(aTransformToSurface);
  } else {
    ComputeEffectiveTransformForMaskLayer(Matrix4x4());
  }
}

void
BasicContainerLayer::ComputeEffectiveTransforms(const Matrix4x4& aTransformToSurface)
{
  // We push groups for container layers if we need to, which always
  // are aligned in device space, so it doesn't really matter how we snap
  // containers.
  Matrix residual;
  Matrix4x4 idealTransform = GetLocalTransform() * aTransformToSurface;
  idealTransform.ProjectTo2D();

  if (!idealTransform.CanDraw2D()) {
    mEffectiveTransform = idealTransform;
    ComputeEffectiveTransformsForChildren(Matrix4x4());
    ComputeEffectiveTransformForMaskLayer(Matrix4x4());
    mUseIntermediateSurface = true;
    return;
  }

  mEffectiveTransform = SnapTransformTranslation(idealTransform, &residual);
  // We always pass the ideal matrix down to our children, so there is no
  // need to apply any compensation using the residual from SnapTransformTranslation.
  ComputeEffectiveTransformsForChildren(idealTransform);

  ComputeEffectiveTransformForMaskLayer(aTransformToSurface);

  Layer* child = GetFirstChild();
  bool hasSingleBlendingChild = false;
  if (!HasMultipleChildren() && child) {
    hasSingleBlendingChild = child->GetMixBlendMode() != CompositionOp::OP_OVER;
  }

  /* If we have a single childand it is not blending,, it can just inherit our opacity,
   * otherwise we need a PushGroup and we need to mark ourselves as using
   * an intermediate surface so our children don't inherit our opacity
   * via GetEffectiveOpacity.
   * Having a mask layer always forces our own push group
   * Having a blend mode also always forces our own push group
   */
  mUseIntermediateSurface =
    GetMaskLayer() ||
    GetForceIsolatedGroup() ||
    (GetMixBlendMode() != CompositionOp::OP_OVER && HasMultipleChildren()) ||
    (GetEffectiveOpacity() != 1.0 && (HasMultipleChildren() || hasSingleBlendingChild));
}

void
BasicContainerLayer::ComputeEffectiveTransforms(const Matrix4x4& aTransformToSurface)
{
  // We push groups for container layers if we need to, which always
  // are aligned in device space, so it doesn't really matter how we snap
  // containers.
  Matrix residual;
  Matrix4x4 idealTransform = GetLocalTransform() * aTransformToSurface;
  if (!Extend3DContext() && !Is3DContextLeaf()) {
    // For 3D transform leaked from extended parent layer.
    idealTransform.ProjectTo2D();
  }

  if (!idealTransform.CanDraw2D()) {
    if (!Extend3DContext() ||
        (!idealTransform.Is2D() && Creates3DContextWithExtendingChildren())) {
      if (!Creates3DContextWithExtendingChildren()) {
        idealTransform.ProjectTo2D();
      }
      mEffectiveTransform = idealTransform;
      ComputeEffectiveTransformsForChildren(Matrix4x4());
      ComputeEffectiveTransformForMaskLayers(Matrix4x4());
      mUseIntermediateSurface = true;
      return;
    }

    mEffectiveTransform = idealTransform;
    ComputeEffectiveTransformsForChildren(idealTransform);
    ComputeEffectiveTransformForMaskLayers(idealTransform);
    mUseIntermediateSurface = false;
    return;
  }

  // With 2D transform or extended 3D context.

  Layer* child = GetFirstChild();
  bool hasSingleBlendingChild = false;
  if (!HasMultipleChildren() && child) {
    hasSingleBlendingChild = child->GetMixBlendMode() != CompositionOp::OP_OVER;
  }

  /* If we have a single childand it is not blending,, it can just inherit our opacity,
   * otherwise we need a PushGroup and we need to mark ourselves as using
   * an intermediate surface so our children don't inherit our opacity
   * via GetEffectiveOpacity.
   * Having a mask layer always forces our own push group
   * Having a blend mode also always forces our own push group
   */
  mUseIntermediateSurface =
    GetMaskLayer() ||
    GetForceIsolatedGroup() ||
    (GetMixBlendMode() != CompositionOp::OP_OVER && HasMultipleChildren()) ||
    (GetEffectiveOpacity() != 1.0 && (HasMultipleChildren() || hasSingleBlendingChild));

  if (!Extend3DContext()) {
    idealTransform.ProjectTo2D();
  }
  mEffectiveTransform =
    !mUseIntermediateSurface ?
    idealTransform : SnapTransformTranslation(idealTransform, &residual);
  Matrix4x4 childTransformToSurface =
    (!mUseIntermediateSurface ||
     (mUseIntermediateSurface && !Extend3DContext() /* 2D */)) ?
    idealTransform : Matrix4x4::From2D(residual);
  ComputeEffectiveTransformsForChildren(childTransformToSurface);

  ComputeEffectiveTransformForMaskLayers(aTransformToSurface);
}