HitTestAnnotation
Annotations, Interaction
Description
Returns the 1-based index of the topmost annotation at a point on the selected page
The test uses QuadPoints for markup, segment distance for Line, PolyLine and Ink, polygon fill or edges, ellipse geometry for Circle and rectangle geometry for other subtypes
Syntax
Function TPDFlib.HitTestAnnotation(X, Y, Tolerance: Double; Options: Integer): Integer;Parameters
| X, Y | Point in the current document unit and origin convention |
|---|---|
| Tolerance | Additional hit radius in current document units, or 0 for exact geometry |
| Options | Bit 1 includes Invisible, Hidden and NoView annotations; bit 2 includes Popup annotations; bit 4 uses bounding rectangles only |
Return values
The topmost 1-based annotation index, or 0 when no eligible annotation is hit
Remarks
Later entries in the page Annots array are treated as higher Z order and tested first; the rectangle is checked before subtype geometry so sparse pages and misses avoid detailed path work