C# Geometry.GetAsPathGeometry方法代码示例

        /// <summary>
        /// The constructor takes the geometry to hit test with.
        /// </summary>
        public GeometryHitTestParameters(Geometry geometry) : base()
        {
            // This ctor guarantees that we are initialized in the following way:
            //
            //  1.  The geometry provided by the user is unmodified
            //  2.  _hitGeometryInternal is a PathGeometry equivilent to the supplied geometry
            //  3.  _hitGeometryInternal.Tranform is a MatrixTransform equivilent to the supplied
            //      geometry.Transform
            //  4.  _origBounds is the untransformed bounds of the _hitGeometryInternal (inner space).
            //  5.  _bounds is the transformed bounds of the _hitGeometryInternal (outer space).
            //  6.  _matrixStack is an empty stack.            

            if (geometry == null)
            {                
                throw new ArgumentNullException("geometry");
            }
            
            // Convert the Geometry to an equivilent PathGeometry up front to prevent
            // conversion on every call to DoesContainWithDetail.  If the geometry is
            // animate this also has the side effect of eliminating animation interplay.
            _hitGeometryInternal = geometry.GetAsPathGeometry();

            // If GetAsPathGeometry was a no-op, force the copy because we do not
            // went to modify the user's Geometry.
            if (object.ReferenceEquals(_hitGeometryInternal, geometry))
            {
                _hitGeometryInternal = _hitGeometryInternal.Clone();
            }
            
            // Convert _hitGeometryInternal.Transform to an equivilent MatrixTransform
            // so that we can aggregate in PushMatrix/PopMatrix without building a
            // TransformCollection.
            Transform origTransform = _hitGeometryInternal.Transform;            
            MatrixTransform newTransform = new MatrixTransform();

            _hitGeometryInternal.Transform = newTransform;

            // Before we initialize MatrixTransform.Matrix, cache the bounds of this
            // geometry without any transforms.
            _origBounds = _hitGeometryInternal.Bounds;

            // If we had a non-Identity transform, update our MatrixTransform.Matrix
            // with its Value.  (Note that when GetAsPathGeometry *isn't* a no-op
            // it applies the transform to the figures and returns with a Geometry
            // with an identity Transform.)
            if (origTransform != null && !origTransform.IsIdentity)
            {
                newTransform.Matrix = origTransform.Value;
            }
            
            // Initialize the current transformed bounds of this Geometry
            _bounds = _hitGeometryInternal.Bounds;
            _matrixStack = new MatrixStack();
        }

        /// <summary>
        /// Static "CreateFromGeometry" method which creates a new PathGeometry from the Geometry specified.
        /// </summary>
        /// <param name="geometry"> 
        /// Geometry - The Geometry which will be used as the basis for the newly created
        /// PathGeometry.  The new Geometry will be based on the current value of all properties.
        /// </param>
        public static PathGeometry CreateFromGeometry(Geometry geometry)
        {
            if (geometry == null)
            {
                return null;
            }

            return geometry.GetAsPathGeometry();
        }