# Copyright (c) 2025-2026 Gigasoft, Inc. All rights reserved.
=== ProEssentials Printing (knowledge rev 4) & Export ===

ProEssentials provides programmatic printing and image export through
PeFunction methods and PeUserInterface.Allow/Dialog properties.

SIMPLE PRINTING:
  PeFunction.PrintGraph(parentHandle, titleString, orientation)
  Shows print dialog, prints the chart. Orientation via DefOrientation enum.
  After printing, ALWAYS call PeFunction.ResetImage(0, 0) to restore screen.

CUSTOM PRINTING (multi-chart per page):
  Use PrintGraphEx for precise layout control with a PrintDocument.
  1. Create PrintDocument, handle PrintPage event
  2. In PrintPage: get Graphics hDC from e.Graphics
  3. Call PeFunction.PrintGraphEx(hDC, x, y, width, height, ...) per chart
  4. After all printing: PeFunction.ResetImage(0, 0)
  Query: pe_query.py function "PrintGraphEx"

IMAGE EXPORT:
  PeFunction.Image provides export to various formats:
  Methods on PeFunction.Image: PngToStream, JpgToStream, etc.
  Call with desired width/height in pixels.
  After export: PeFunction.ResetImage(0, 0) to restore screen rendering.

DPI CONTROL:
  ExportImageDpi controls the resolution for export operations.
  PrintDpi affects printer output resolution.
  For high-quality print: set DPI before printing, reset after.

EXPORT DIALOGS:
  PeUserInterface.Allow.Exporting -- let users export via right-click menu.
  PeUserInterface.Menu.ExportDialog -- show export dialog programmatically.

EMF EXPORT:
  EmfType and EmfDC properties control Enhanced Metafile output.
  Use for vector graphics (scalable, editable in Illustrator/Visio).

PRINT STYLE:
  PrintStyleControl -- adjust line weights and sizes for print vs. screen.
  Typically print needs heavier lines than screen display.

CRITICAL PATTERN -- ALWAYS RESET:
  ANY printing or export operation temporarily modifies the chart's
  rendering target. You MUST call PeFunction.ResetImage(0, 0) afterward
  or the on-screen chart will not render correctly.

  Known anomaly: HObject documentation references this pattern. The
  HObject property (PeSpecial.HObject) provides the Win32 handle needed
  for advanced DLL-level printing operations.

KEY: pe_query.py function "PrintGraph"
  pe_query.py search "export image"
  pe_query.py recipe "printing"