Support display of BMP images on MS-Windows

* src/w32image.c (w32_can_use_native_image_api): Support BMP
images.
* src/image.c (syms_of_image) <Qbmp>: New symbol.
[HAVE_NTGUI]: Add 'bmp' to list of supported image types.

* doc/lispref/display.texi (Image Formats): Document built-in
support for BMP images.

* etc/NEWS: Announce the change.

doc/lispref/display.texi

@@ -5507,6 +5507,12 @@ symbol}.  The symbols for the above formats are, respectively,
 @code{pbm}, @code{xbm}, @code{xpm}, @code{gif}, @code{jpeg},
 @code{tiff}, @code{png}, @code{svg}, and @code{webp}.
 
+  On some platforms, the built-in image support that doesn't require
+any optional libraries includes BMP images.@footnote{
+On MS-Windows, this requires @code{w32-use-native-image-API} to be set
+non-@code{nil}.
+}
+
   Furthermore, if you build Emacs with ImageMagick
 (@code{libMagickWand}) support, Emacs can display any image format
 that ImageMagick can.  @xref{ImageMagick Images}.  All images

etc/NEWS

@@ -1821,6 +1821,11 @@ follow the system's dark mode: GUI frames use the appropriate light or
 dark title bar and scroll bars, based on the user's Windows-wide color
 settings.
 
++++
+*** Emacs now supports display of BMP images using native image APIs.
+When 'w32-use-native-image-API' is non-nil, Emacs on MS-Windows now
+has built-in support for displaying BMP images.
+
 
 ----------------------------------------------------------------------
 This file is part of GNU Emacs.

src/image.c

@@ -11558,6 +11558,8 @@ non-numeric, there is no explicit limit on the size of images.  */);
 # ifdef HAVE_NTGUI
   DEFSYM (Qgdiplus, "gdiplus");
   DEFSYM (Qshlwapi, "shlwapi");
+  DEFSYM (Qbmp, "bmp");
+  add_image_type (Qbmp);
 # endif
 #endif
 

src/w32image.c

@@ -253,6 +253,7 @@ w32_can_use_native_image_api (Lisp_Object type)
 	|| EQ (type, Qpng)
 	|| EQ (type, Qgif)
 	|| EQ (type, Qtiff)
+	|| EQ (type, Qbmp)
 	|| EQ (type, Qnative_image)))
     {
       /* GDI+ can also display BMP, Exif, ICON, WMF, and EMF images.