HPDFRenderHeadlessPagePNG

function HPDFRenderHeadlessPagePNG(const Access: THPDFHeadlessRenderAccess;
  Destination: TStream; const Options: THPDFHeadlessRenderOptions):
  THPDFHeadlessRenderResult;

Declared in HPDFHeadlessCairoDevice; renders one borrowed loaded page to an RGB PNG on a white image surface

Access must provide valid page/resources and object, stream, font, and permission callbacks; the document and its optional cancellation token remain caller-owned and must stay alive and unchanged for the call

Destination is a required caller-owned writable stream; the function writes at its current position and neither closes nor clears it

Rendering, budget validation, and PNG encoding finish in private storage before destination writes begin, so those failures preserve existing destination bytes

A final destination I/O failure can leave bytes accepted by the stream; use the file overload when atomic file publication is required

Options control scale, appearances, and resource limits; returned counters describe the successful render

See Native Linux Cairo renderer for dependencies, supported content, conservative font admission, and failure boundaries

Supported annotations without a normal appearance use temporary annotation appearances without modifying the source graph