Measure Method

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Measure Method

Calculates the rectangle on the device context that would contain a collection of strokes if the strokes were drawn with the InkRenderer object using the DrawStroke method.

Declaration

[C++]

HRESULT Measure (
    [in] IInkStrokes* strokes,
    [out, retval] IInkRectangle **Rectangle
);

[Microsoft® Visual Basic® 6.0]

Public Function Measure( _
    strokes As InkStrokes _
) As InkRectangle

Parameters

strokes

[in] The collection of strokes to measure.

Rectangle

[out] Returns the rectangle on the device context that would contain the strokes if they were drawn with the DrawStroke method of the InkRenderer object. The strokes must contain x- and y-coordinates to calculate the rectangle. Otherwise, the method returns an empty rectangle.

Return Value

HRESULT value Description
S_OK Success.
E_POINTER A parameter contained an invalid pointer.
E_INVALIDARG Invalid display handle.
E_INK_INCOMPATIBLE_OBJECT The strokes parameter does not point to a valid object.
E_INK_MISMATCHED_INK_OBJECT The strokes parameter is associated with a different InkDisp object.
E_INK_EXCEPTION An exception occurred inside the method.
E_UNEXPECTED Unexpected parameter or property type.

Remarks

This is accurate only if you pass the same arguments to both Measure and DrawStroke.

Since the bounding box is affected by the pen width, this width is scaled appropriately for the InkRenderer's view transform. To do this, the pen width is multiplied by the square root of the determinant of the view transform. The height and width of the bounding box are expanded by half this amount in each direction, and the right and bottom sides are incremented by one.

For example, consider that the pen width is originally 53, the square root of the determinant of the view transform is 50, and the bounding box is (0, 0, 1000, 1000). The pen width adjustment to the bounding box in each direction is calculated as (53 * 50) / 2, and the right and bottom sides are incremented by one. This results in a rendered bounding box of (-1325, -1325, 2326, 2326).

Example

[Visual Basic 6.0]

This Visual Basic 6.0 example gets the bounding rectangle for the strokes in the InkCollector, theInkCollector.

Dim theMeasure As InkRectangle
Set theMeasure = theInkCollector.Renderer.Measure(theInkCollector.Ink.Strokes)

Applies To