Renders a caller-owned bitmap for one TPdfPageDifference returned by CompareWith
function RenderDiffOverlay(Other: TPdf; const Difference: TPdfPageDifference; const Options: TPdfDocumentDiffOptions): TBitmap;
The bitmap uses the selected RenderWidth and RenderHeight, marks modified or deleted content in red, inserted content in green and moved pages in blue
Visual regions use pixel coordinates in the comparison rendering; use the same options and unchanged input documents as the comparison, and free the returned bitmap after exporting or displaying it
Both current page selections are restored; invalid indices and render sizes raise an exception