The ANNPOINTEROPTIONS structure contains information about the pointer options of an ANNOBJECT_POINTER or ANNOBJECT_AUTOMATION object.
For an ANNOBJECT_POINTER object, the length of the head is determined as a linear function of the line width of the object as follow:
LengthOfHead = LineWidth * nPointerHeadM + nPointerHeadB
Setting nPointerHeadM to 1 or more causes the pointer head length to change as the line width changes. Setting nPointerHeadM to 0, and nPointerHeadB to a non-zero value causes the pointer head length to stay constant, regardless of the line width.
When you create an ANNOBJECT_POINTER object in the automation mode, the values for nPointerHeadM and nPointerHeadB are being obtained from the automation object.
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