Make use of MS-Windows native image API be selectable at run time

* configure.ac: Minor cleanup in how w32image.o is added to the
build when native image APIs are requested.

* src/w32gui.h (w32_load_image, w32_can_use_native_image_api)
(w32_gdiplus_shutdown): Move prototypes from w32term.h here, since
w32.c doesn't include w32term.h.
* src/image.c (struct image_type): No need to pass TYPE to the
'valid_p' method.  All callers changed.
(initialize_image_type) [HAVE_NATIVE_IMAGE_API]: Call
'image_can_use_native_api' before trying image-specific methods.
(image_can_use_native_api): New function.
(image_types): Remove the native_image_type parts.
(syms_of_image): New symbol 'native-image'.
(parse_image_spec): Accept native-image "type" for any image type.
* src/w32term.c (syms_of_w32term): New variable
'w32-use-native-image-API'.
* src/w32image.c: (w32_can_use_native_image_api): New function.
(gdiplus_init): Rename from w32_gdiplus_startup. Simplify code.
Move the call to GdiplusStartup to a separate function.  Use
ordinal number for SHCreateMemStream if cannot load it by name.
(w32_load_image): Ignore Win32Error status from
w32_select_active_frame.
Move DEFSYMs from here...
* src/image.c (syms_of_image) [HAVE_NATIVE_IMAGE_API]: ...to here.

* etc/NEWS: Update the entry about native image API use.

1 files changed, 9 insertions, 7 deletions

diff --git a/configure.ac b/configure.ac
index 41a1860493a..b0a2cc466b9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -433,7 +433,7 @@ OPTION_DEFAULT_ON([libsystemd],[don't compile with libsystemd support])
 OPTION_DEFAULT_ON([cairo],[don't compile with Cairo drawing])
 OPTION_DEFAULT_ON([xml2],[don't compile with XML parsing support])
 OPTION_DEFAULT_OFF([imagemagick],[compile with ImageMagick image support])
-OPTION_DEFAULT_OFF([native-image-api], [use native API's (GDI+ on Windows) for JPEG/TIFF/GIFF/PNG])
+OPTION_DEFAULT_ON([native-image-api], [use native image APIs (GDI+ on Windows)])
 OPTION_DEFAULT_ON([json], [don't compile with native JSON support])
 
 OPTION_DEFAULT_ON([xft],[don't use XFT for anti aliased fonts])
@@ -2127,7 +2127,7 @@ LIB_WSOCK32=
 NTLIB=
 CM_OBJ="cm.o"
 XARGS_LIMIT=
-HAVE_NATIVE_IMAGE_API=no
+NATIVE_IMAGE_API=no
 if test "${HAVE_W32}" = "yes"; then
   AC_DEFINE(HAVE_NTGUI, 1, [Define to use native MS Windows GUI.])
   if test "$with_toolkit_scroll_bars" = "no"; then
@@ -2156,12 +2156,14 @@ if test "${HAVE_W32}" = "yes"; then
     # the rc file), not a linker script.
     W32_RES_LINK="-Wl,emacs.res"
   else
+    W32_OBJ="$W32_OBJ w32.o w32console.o w32heap.o w32inevt.o w32proc.o"
+    dnl FIXME: This should probably be supported for Cygwin/w32 as
+    dnl well, but the Cygwin build needs to link against -lgdiplus
     if test "${with_native_image_api}" = yes; then
-      AC_DEFINE(HAVE_NATIVE_IMAGE_API, 1, [Define to use MS Windows GDI+ for images.])
-      HAVE_NATIVE_IMAGE_API=yes
-      W32_NATIVE_IMAGE_API="w32image.o"
+      AC_DEFINE(HAVE_NATIVE_IMAGE_API, 1, [Define to use native OS APIs for images.])
+      NATIVE_IMAGE_API="yes (w32)"
+      W32_OBJ="$W32_OBJ w32image.o"
     fi
-    W32_OBJ="$W32_OBJ w32.o w32console.o w32heap.o w32inevt.o w32proc.o $W32_NATIVE_IMAGE_API"
     W32_LIBS="$W32_LIBS -lwinmm -lusp10 -lgdi32 -lcomdlg32"
     W32_LIBS="$W32_LIBS -lmpr -lwinspool -lole32 -lcomctl32"
     W32_RES_LINK="\$(EMACSRES)"
@@ -5710,7 +5712,7 @@ AS_ECHO(["  Does Emacs use -lXaw3d?                                 ${HAVE_XAW3D
   Does Emacs use cairo?                                   ${HAVE_CAIRO}
   Does Emacs use -llcms2?                                 ${HAVE_LCMS2}
   Does Emacs use imagemagick?                             ${HAVE_IMAGEMAGICK}
-  Does Emacs use native API for images?                   ${HAVE_NATIVE_IMAGE_API}
+  Does Emacs use native APIs for images?                  ${NATIVE_IMAGE_API}
   Does Emacs support sound?                               ${HAVE_SOUND}
   Does Emacs use -lgpm?                                   ${HAVE_GPM}
   Does Emacs use -ldbus?                                  ${HAVE_DBUS}