THPDFViewer Region Snapshots

Renders a selected PDF page rectangle so memory use depends on the region rather than the whole page

Declarations

function CreatePageRegionSnapshot(PageIndex: Integer; const PageRect: THPDFRectangle; DPI: Integer= 150): TBitmap;
function CreateCurrentPageRegionSnapshot(const PageRect: THPDFRectangle; DPI: Integer= 150): TBitmap;

Region handling

• The input rectangle uses PDF points and a lower-left origin
• Reversed left/right or bottom/top values are ordered automatically
• The region is intersected with the page MediaBox before rendering
• An empty intersection or invalid page returns nil
• DPI values are clamped from 12 through 2400
• The returned bitmap includes both the PDF page rotation and current ViewRotation

Example

Region.Left := 72;
Region.Bottom := 72;
Region.Right := 288;
Region.Top := 216;
Bitmap := Model.CreateCurrentPageRegionSnapshot(Region, 300);