/// <summary>
/// Appends the entire input DrawingCollection, while only firing a single set of
/// public events. If an exception is thrown from the public events, the
/// Append operation is rolled back.
/// </summary>
internal void TransactionalAppend(DrawingCollection collectionToAppend)
{
// Use appendCount to avoid inconsistencies & runaway loops when
// this == collectionToAppend, and to ensure collectionToAppend.Count
// is only evaluated once.
int appendCount = collectionToAppend.Count;
// First, append the collection
for (int i = 0; i < appendCount; i++)
{
AddWithoutFiringPublicEvents(collectionToAppend.Internal_GetItem(i));
}
// Fire the public Changed event after all the elements have been added.
//
// If an exception is thrown, then the Append operation is rolled-back without
// firing additional events.
try
{
FireChanged();
}
catch (Exception)
{
// Compute the number of elements that existed before the append
int beforeAppendCount = Count - appendCount;
// Remove the appended elements in reverse order without firing Changed events.
for (int i = Count - 1; // Start at the current last index
i >= beforeAppendCount; // Until the previous last index
i-- // Move to the preceding index
)
{
RemoveAtWithoutFiringPublicEvents(i);
}
// Avoid firing WritePostscript events (e.g., OnChanged) after rolling-back
// the current operation.
//
// This ensures that only a single set of events is fired for both exceptional &
// typical cases, and it's likely that firing events would cause another exception.
throw;
}
}
internal override DUCE.ResourceHandle AddRefOnChannelCore(DUCE.Channel channel)
{
if (_duceResource.CreateOrAddRefOnChannel(this, channel, System.Windows.Media.Composition.DUCE.ResourceType.TYPE_DRAWINGGROUP))
{
Geometry vClipGeometry = ClipGeometry;
if (vClipGeometry != null)
{
((DUCE.IResource)vClipGeometry).AddRefOnChannel(channel);
}
Brush vOpacityMask = OpacityMask;
if (vOpacityMask != null)
{
((DUCE.IResource)vOpacityMask).AddRefOnChannel(channel);
}
Transform vTransform = Transform;
if (vTransform != null)
{
((DUCE.IResource)vTransform).AddRefOnChannel(channel);
}
GuidelineSet vGuidelineSet = GuidelineSet;
if (vGuidelineSet != null)
{
((DUCE.IResource)vGuidelineSet).AddRefOnChannel(channel);
}
DrawingCollection vChildren = Children;
if (vChildren != null)
{
int count = vChildren.Count;
for (int i = 0; i < count; i++)
{
((DUCE.IResource)vChildren.Internal_GetItem(i)).AddRefOnChannel(channel);
}
}
AddRefOnChannelAnimations(channel);
UpdateResource(channel, true /* skip "on channel" check - we already know that we're on channel */);
}
return(_duceResource.GetHandle(channel));
}
internal override void ReleaseOnChannelCore(DUCE.Channel channel)
{
Debug.Assert(_duceResource.IsOnChannel(channel));
if (_duceResource.ReleaseOnChannel(channel))
{
Geometry vClipGeometry = ClipGeometry;
if (vClipGeometry != null)
{
((DUCE.IResource)vClipGeometry).ReleaseOnChannel(channel);
}
Brush vOpacityMask = OpacityMask;
if (vOpacityMask != null)
{
((DUCE.IResource)vOpacityMask).ReleaseOnChannel(channel);
}
Transform vTransform = Transform;
if (vTransform != null)
{
((DUCE.IResource)vTransform).ReleaseOnChannel(channel);
}
GuidelineSet vGuidelineSet = GuidelineSet;
if (vGuidelineSet != null)
{
((DUCE.IResource)vGuidelineSet).ReleaseOnChannel(channel);
}
DrawingCollection vChildren = Children;
if (vChildren != null)
{
int count = vChildren.Count;
for (int i = 0; i < count; i++)
{
((DUCE.IResource)vChildren.Internal_GetItem(i)).ReleaseOnChannel(channel);
}
}
ReleaseOnChannelAnimations(channel);
}
}
/// <summary>
/// Calls methods on the DrawingContext that are equivalent to the
/// Drawing with the Drawing's current value.
/// </summary>
internal override void WalkCurrentValue(DrawingContextWalker ctx)
{
int popCount = 0;
// We avoid unneccessary ShouldStopWalking checks based on assumptions
// about when ShouldStopWalking is set. Guard that assumption with an
// assertion.
//
// ShouldStopWalking is currently only set during a hit-test walk after
// an object has been hit. Because a DrawingGroup can't be hit until after
// the first Drawing is tested, this method doesn't check ShouldStopWalking
// until after the first child.
//
// We don't need to add this check to other Drawing subclasses for
// the same reason -- if the Drawing being tested isn't a DrawingGroup,
// they are always the 'first child'.
//
// If this assumption is ever broken then the ShouldStopWalking
// check should be done on the first child -- including in the
// WalkCurrentValue method of other Drawing subclasses.
Debug.Assert(!ctx.ShouldStopWalking);
//
// Draw the transform property
//
// Avoid calling PushTransform if the base value is set to the default and
// no animations have been set on the property.
if (!IsBaseValueDefault(DrawingGroup.TransformProperty) ||
(null != AnimationStorage.GetStorage(this, DrawingGroup.TransformProperty)))
{
ctx.PushTransform(Transform);
popCount++;
}
//
// Draw the clip property
//
// Avoid calling PushClip if the base value is set to the default and
// no animations have been set on the property.
if (!IsBaseValueDefault(DrawingGroup.ClipGeometryProperty) ||
(null != AnimationStorage.GetStorage(this, DrawingGroup.ClipGeometryProperty)))
{
ctx.PushClip(ClipGeometry);
popCount++;
}
//
// Draw the opacity property
//
// Avoid calling PushOpacity if the base value is set to the default and
// no animations have been set on the property.
if (!IsBaseValueDefault(DrawingGroup.OpacityProperty) ||
(null != AnimationStorage.GetStorage(this, DrawingGroup.OpacityProperty)))
{
// Push the current value of the opacity property, which
// is what Opacity returns.
ctx.PushOpacity(Opacity);
popCount++;
}
// Draw the opacity mask property
//
if (OpacityMask != null)
{
ctx.PushOpacityMask(OpacityMask);
popCount++;
}
//
// Draw the effect property
//
// Push the current value of the effect property, which
// is what BitmapEffect returns.
if (BitmapEffect != null)
{
// Disable warning about obsolete method. This code must remain active
// until we can remove the public BitmapEffect APIs.
#pragma warning disable 0618
ctx.PushEffect(BitmapEffect, BitmapEffectInput);
#pragma warning restore 0618
popCount++;
}
//
// Draw the Children collection
//
// Get the current value of the children collection
DrawingCollection collection = Children;
// Call Walk on each child
if (collection != null)
{
for (int i = 0; i < collection.Count; i++)
{
Drawing drawing = collection.Internal_GetItem(i);
if (drawing != null)
{
drawing.WalkCurrentValue(ctx);
// Don't visit the remaining children if the previous
// child caused us to stop walking.
if (ctx.ShouldStopWalking)
{
break;
}
}
}
}
//
// Call Pop() for every Push
//
// Avoid placing this logic in a finally block because if an exception is
// thrown, the Walk is simply aborted. There is no requirement to Walk
// through Pop instructions when an exception is thrown.
//
for (int i = 0; i < popCount; i++)
{
ctx.Pop();
}
}
//------------------------------------------------------
//
// Public Properties
//
//------------------------------------------------------
private static void ChildrenPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
// The first change to the default value of a mutable collection property (e.g. GeometryGroup.Children)
// will promote the property value from a default value to a local value. This is technically a sub-property
// change because the collection was changed and not a new collection set (GeometryGroup.Children.
// Add versus GeometryGroup.Children = myNewChildrenCollection). However, we never marshalled
// the default value to the compositor. If the property changes from a default value, the new local value
// needs to be marshalled to the compositor. We detect this scenario with the second condition
// e.OldValueSource != e.NewValueSource. Specifically in this scenario the OldValueSource will be
// Default and the NewValueSource will be Local.
if (e.IsASubPropertyChange &&
(e.OldValueSource == e.NewValueSource))
{
return;
}
DrawingGroup target = ((DrawingGroup)d);
// If this is both non-null and mutable, we need to unhook the Changed event.
DrawingCollection oldCollection = null;
DrawingCollection newCollection = null;
if ((e.OldValueSource != BaseValueSourceInternal.Default) || e.IsOldValueModified)
{
oldCollection = (DrawingCollection)e.OldValue;
if ((oldCollection != null) && !oldCollection.IsFrozen)
{
oldCollection.ItemRemoved -= target.ChildrenItemRemoved;
oldCollection.ItemInserted -= target.ChildrenItemInserted;
}
}
// If this is both non-null and mutable, we need to hook the Changed event.
if ((e.NewValueSource != BaseValueSourceInternal.Default) || e.IsNewValueModified)
{
newCollection = (DrawingCollection)e.NewValue;
if ((newCollection != null) && !newCollection.IsFrozen)
{
newCollection.ItemInserted += target.ChildrenItemInserted;
newCollection.ItemRemoved += target.ChildrenItemRemoved;
}
}
if (oldCollection != newCollection && target.Dispatcher != null)
{
using (CompositionEngineLock.Acquire())
{
DUCE.IResource targetResource = (DUCE.IResource)target;
int channelCount = targetResource.GetChannelCount();
for (int channelIndex = 0; channelIndex < channelCount; channelIndex++)
{
DUCE.Channel channel = targetResource.GetChannel(channelIndex);
Debug.Assert(!channel.IsOutOfBandChannel);
Debug.Assert(!targetResource.GetHandle(channel).IsNull);
// resource shouldn't be null because
// 1) If the field is one of our collections, we don't allow null elements
// 2) Codegen already made sure the collection contains DUCE.IResources
// ... so we'll Assert it
if (newCollection != null)
{
int count = newCollection.Count;
for (int i = 0; i < count; i++)
{
DUCE.IResource resource = newCollection.Internal_GetItem(i) as DUCE.IResource;
Debug.Assert(resource != null);
resource.AddRefOnChannel(channel);
}
}
if (oldCollection != null)
{
int count = oldCollection.Count;
for (int i = 0; i < count; i++)
{
DUCE.IResource resource = oldCollection.Internal_GetItem(i) as DUCE.IResource;
Debug.Assert(resource != null);
resource.ReleaseOnChannel(channel);
}
}
}
}
}
target.PropertyChanged(ChildrenProperty);
}
//------------------------------------------------------
//
// Internal Methods
//
//------------------------------------------------------
#region Internal Methods
internal override void UpdateResource(DUCE.Channel channel, bool skipOnChannelCheck)
{
// If we're told we can skip the channel check, then we must be on channel
Debug.Assert(!skipOnChannelCheck || _duceResource.IsOnChannel(channel));
if (skipOnChannelCheck || _duceResource.IsOnChannel(channel))
{
base.UpdateResource(channel, skipOnChannelCheck);
// Read values of properties into local variables
DrawingCollection vChildren = Children;
Geometry vClipGeometry = ClipGeometry;
Brush vOpacityMask = OpacityMask;
Transform vTransform = Transform;
GuidelineSet vGuidelineSet = GuidelineSet;
// Obtain handles for properties that implement DUCE.IResource
DUCE.ResourceHandle hClipGeometry = vClipGeometry != null ? ((DUCE.IResource)vClipGeometry).GetHandle(channel) : DUCE.ResourceHandle.Null;
DUCE.ResourceHandle hOpacityMask = vOpacityMask != null ? ((DUCE.IResource)vOpacityMask).GetHandle(channel) : DUCE.ResourceHandle.Null;
DUCE.ResourceHandle hTransform;
if (vTransform == null ||
Object.ReferenceEquals(vTransform, Transform.Identity)
)
{
hTransform = DUCE.ResourceHandle.Null;
}
else
{
hTransform = ((DUCE.IResource)vTransform).GetHandle(channel);
}
DUCE.ResourceHandle hGuidelineSet = vGuidelineSet != null ? ((DUCE.IResource)vGuidelineSet).GetHandle(channel) : DUCE.ResourceHandle.Null;
// Obtain handles for animated properties
DUCE.ResourceHandle hOpacityAnimations = GetAnimationResourceHandle(OpacityProperty, channel);
// Store the count of this resource's contained collections in local variables.
int ChildrenCount = (vChildren == null) ? 0 : vChildren.Count;
// Pack & send command packet
DUCE.MILCMD_DRAWINGGROUP data;
unsafe
{
data.Type = MILCMD.MilCmdDrawingGroup;
data.Handle = _duceResource.GetHandle(channel);
data.ChildrenSize = (uint)(sizeof(DUCE.ResourceHandle) * ChildrenCount);
data.hClipGeometry = hClipGeometry;
if (hOpacityAnimations.IsNull)
{
data.Opacity = Opacity;
}
data.hOpacityAnimations = hOpacityAnimations;
data.hOpacityMask = hOpacityMask;
data.hTransform = hTransform;
data.hGuidelineSet = hGuidelineSet;
data.EdgeMode = (EdgeMode)GetValue(RenderOptions.EdgeModeProperty);
data.bitmapScalingMode = (BitmapScalingMode)GetValue(RenderOptions.BitmapScalingModeProperty);
data.ClearTypeHint = (ClearTypeHint)GetValue(RenderOptions.ClearTypeHintProperty);
channel.BeginCommand(
(byte *)&data,
sizeof(DUCE.MILCMD_DRAWINGGROUP),
(int)(data.ChildrenSize)
);
// Copy this collection's elements (or their handles) to reserved data
for (int i = 0; i < ChildrenCount; i++)
{
DUCE.ResourceHandle resource = ((DUCE.IResource)vChildren.Internal_GetItem(i)).GetHandle(channel);;
channel.AppendCommandData(
(byte *)&resource,
sizeof(DUCE.ResourceHandle)
);
}
channel.EndCommand();
}
}
}