/// <summary>
/// DrawDrawing -
/// Draw a Drawing by appending a sub-Drawing to the current Drawing.
/// </summary>
/// <param name="drawing"> The drawing to draw. </param>
public override void DrawDrawing(
Drawing drawing)
{
if (drawing != null)
{
drawing.WalkCurrentValue(this);
}
}
/// <summary>
/// Determines whether or not a point exists in a Drawing
/// </summary>
/// <param name="drawing"> Drawing to hit-test</param>
/// <param name="point"> Point to hit-test for </param>
/// <returns>
/// 'true' if the point exists within the drawing, 'false' otherwise
/// </returns>
internal static bool HitTestPoint(Drawing drawing, Point point)
{
if (drawing != null)
{
HitTestDrawingContextWalker ctx = new HitTestWithPointDrawingContextWalker(point);
drawing.WalkCurrentValue(ctx);
return ctx.IsHit;
}
else
{
return false;
}
}
/// <summary>
/// Determines whether or not a point exists in a Drawing
/// </summary>
/// <param name="drawing"> Drawing to hit-test</param>
/// <param name="point"> Point to hit-test for </param>
/// <returns>
/// 'true' if the point exists within the drawing, 'false' otherwise
/// </returns>
internal static bool HitTestPoint(Drawing drawing, Point point)
{
if (drawing != null)
{
HitTestDrawingContextWalker ctx = new HitTestWithPointDrawingContextWalker(point);
drawing.WalkCurrentValue(ctx);
return(ctx.IsHit);
}
else
{
return(false);
}
}
/// <summary>
/// Hit-tests a Drawing against a PathGeometry
/// </summary>
/// <param name="drawing"> The drawing to hit test against </param>
/// <param name="geometry"> The geometry (in local coordinate space) to hit test. </param>
/// <returns>
/// IntersectionDetail that describes the hit result
/// </returns>
internal static IntersectionDetail HitTestGeometry(Drawing drawing, PathGeometry geometry)
{
if (drawing != null)
{
HitTestDrawingContextWalker ctx =
new HitTestWithGeometryDrawingContextWalker(geometry);
drawing.WalkCurrentValue(ctx);
return ctx.IntersectionDetail;
}
else
{
return IntersectionDetail.Empty;
}
}
/// <summary>
/// Hit-tests a Drawing against a PathGeometry
/// </summary>
/// <param name="drawing"> The drawing to hit test against </param>
/// <param name="geometry"> The geometry (in local coordinate space) to hit test. </param>
/// <returns>
/// IntersectionDetail that describes the hit result
/// </returns>
internal static IntersectionDetail HitTestGeometry(Drawing drawing, PathGeometry geometry)
{
if (drawing != null)
{
HitTestDrawingContextWalker ctx =
new HitTestWithGeometryDrawingContextWalker(geometry);
drawing.WalkCurrentValue(ctx);
return(ctx.IntersectionDetail);
}
else
{
return(IntersectionDetail.Empty);
}
}
/// <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();
}
}
/// <summary>
/// DrawDrawing -
/// Draw a Drawing by appending a sub-Drawing to the current Drawing.
/// </summary>
/// <param name="drawing"> The drawing to draw. </param>
public override void DrawDrawing(
Drawing drawing)
{
if (drawing != null)
{
drawing.WalkCurrentValue(this);
}
}
