HitTest (StrokeCollection)
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Returns a collection of strokes that are intersected by the points in a specified StylusPointCollection.
retval = object.HitTest(stylusPoints)
Arguments
stylusPoints |
The collection of stylus points used to check for intersection with the StrokeCollection. |
Return Value
Type: StrokeCollection
A collection of strokes that are intersected by the points in the specified StylusPointCollection.
Remarks
For a StrokeCollectionsc that contains strokes S0 - S2, and a StylusPointCollectionspc that contains points P0 - P3, the following HitTest call:
sc.HitTest(spc)
returns a StrokeCollection that containing S1 and S2.
Hit-test results
.png "Hit-Test for StrokeCollection")
Example
// Add the new points to the Stroke we're working with
// or delete strokes if we are in erase mode.
function inkPresenterMouseMove(sender, args)
{
var stylusPoints = args.getStylusPoints(sender);
// Erase Mode?
if (lastErasePoint != null)
{
// Connect the point from previous mouse event
// to the current collection of stylus points.
stylusPoints.insert(0, lastErasePoint);
var hitStrokes = sender.strokes.hitTest(stylusPoints);
// Remove the strokes that were intersected above.
for (var i = 0; i < hitStrokes.Count; i++)
{
sender.strokes.remove(hitStrokes.getItem(i));
}
// Update the cached last erase point.
lastErasePoint = stylusPoints.getItem(stylusPoints.count-1);
}
// Ink Mode?
if (newStroke != null)
{
newStroke.stylusPoints.addStylusPoints(stylusPoints);
}
}