Define behaviors of FPDF_RenderPageBitmap_Retail and FPDF_FFLDraw.

public/fpdfview.h

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 // NOTE: External docs refer to this file as "fpdfview.h", so do not rename
 // despite lack of consistency with other public files.
 
 #ifndef PUBLIC_FPDFVIEW_H_
@@ skipping 577 matching lines @@
 //          start_y     -   Top pixel position of the display area in bitmap
 //                          coordinates.
 //          size_x      -   Horizontal size (in pixels) for displaying the page.
 //          size_y      -   Vertical size (in pixels) for displaying the page.
 //          rotate      -   Page orientation:
 //                            0 (normal)
 //                            1 (rotated 90 degrees clockwise)
 //                            2 (rotated 180 degrees)
 //                            3 (rotated 90 degrees counter-clockwise)
 //          flags       -   0 for normal display, or combination of flags
-//                          defined above.
+//                          defined above. With FPDF_ANNOT flag, it renders all
+//                          annotations that does not require user-interaction,
+//                          which are all annotations except widget and popup
+//                          annotations.
 // Return value:
 //          None.
 DLLEXPORT void STDCALL FPDF_RenderPageBitmap(FPDF_BITMAP bitmap,
                                              FPDF_PAGE page,
                                              int start_x,
                                              int start_y,
                                              int size_x,
                                              int size_y,
                                              int rotate,
                                              int flags);
@@ skipping 360 matching lines @@
 // Function: FPDF_BStr_Clear
 //          Helper function to clear a byte string.
 DLLEXPORT FPDF_RESULT STDCALL FPDF_BStr_Clear(FPDF_BSTR* str);
 #endif  // PDF_ENABLE_XFA
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif  // PUBLIC_FPDFVIEW_H_