PressureFactor Property

Gets or sets the pressure factor of the stylus on the screen.

XAML
<StylusPoint PressureFactor="Double" .../>
Scripting
value = object.PressureFactor
object.PressureFactor = value

Property Value

Double

The pressure factor of the stylus on the screen.

This property is read/write. The default value is 0.5.

Remarks

The allowed range is 0 to 1.0. Values obtained from input will always be within this range. Setting the value to outside this range throws an error.

The value is a percentage of the total possible pressure.

The typical scenario for this property is to modify the DrawingAttributes on the basis of the PressureFactor captured in a StylusPoint obtained from user input, although note that while PressureFactor comes from individual points, DrawingAttributes must apply to an entire Stroke.

Examples

The following example uses the PressureFactor property to determine the size of a stroke. The PressureFactor is obtained from the first StylusPoint of each stroke, then the stroke Width and Height is calculated by multiplying the PressureFactor by 20.

JavaScript
var agCtrl;
var inkPresenter; // Corresponds to InkPresenter element in xaml
var newStroke = null; // The Stroke variable we'll use here in mouse handlers
var daWidth;
var daHeight;
function root_Loaded(sender, args) 
{
    // Get the html object which contains the Silverlight plug-in
    agCtrl = sender.GetHost();
    inkPresenter = sender.findname("inkPresenterElement");
}
// Capture mouse movement when the left button is pressed then create the stroke.
function InkPresenterMouseDown(sender,args)
{
   inkPresenter.CaptureMouse();
   newStroke = agCtrl.content.createFromXaml('<Stroke/>');
   
   // Get the DeviceType
   if(args.GetStylusInfo().deviceType == "Stylus")
   {
     var sps = args.GetStylusPoints(inkPresenter);
     SetStylusStrokeSize(sps);
   }
   // If the device type is not a stylus then use the default stroke height and width.
   else
   {
     daWidth = 3;
     daHeight = 3;
   }
   
   // Set the drawing attributes properties
   newStroke.DrawingAttributes.Width = daWidth;
   newStroke.DrawingAttributes.Height = daHeight;
   newStroke.DrawingAttributes.Color = "Blue";
   newStroke.DrawingAttributes.OutlineColor = "Orange";
   
   newStroke.StylusPoints.AddStylusPoints(args.GetStylusPoints(inkPresenter));
   inkPresenter.Strokes.Add(newStroke);
}
// Add the new points to the Stroke we're working with
function InkPresenterMouseMove(sender,args)
{
   if (newStroke != null)
   {
      newStroke.StylusPoints.AddStylusPoints(args.GetStylusPoints(inkPresenter));
   }
}
// Release the mouse
function InkPresenterMouseUp(sender,args)
{
   newStroke = null;
}
// Set the size of the stroke based on the initial pressureFactor of the stroke.
function SetStylusStrokeSize(sps)
{
    var p;
    // Set variable p to the first StylusPoint in the Stroke
    p = sps.getItem(0).pressureFactor;
    daWidth = p * 20.0;
    daHeight = p * 20.0;
}

Applies To

StylusPoint

See Also

Ink Support In Microsoft Silverlight
StylusPoint Object