Initial version of native image API support for MS-Windows

* src/w32image.c: New file.
* src/w32term.h: Add prototypes of 'w32_load_image',
'w32_gdiplus_startup', 'w32_gdiplus_shutdown', and
'w32_query_frame_background_color'.
* src/w32term.c (w32_query_frame_background_color): No longer
static.
* src/w32.c (term_ntproc) [HAVE_GDIPLUS]: Call
'w32_gdiplus_shutdown'.
* src/image.c (struct image_type) <valid_p>: Accept an additional
argument, the image type.  All implementations changed.
(init_native_image_functions, native_image_p, native_image_load)
[HAVE_NATIVE_IMAGE_API]: New methods for "native image type".
(initialize_image_type) [HAVE_NATIVE_IMAGE_API]: Call
'init_native_image_functions'.
(image_types) [HAVE_NATIVE_IMAGE_API]: Add settings for native
image API.
(lookup_image_type) [HAVE_NATIVE_IMAGE_API]: Initialize native
functions if needed.

* lisp/term/w32-win.el (dynamic-library-alist): Add gdiplus and
shlwapi.

* etc/NEWS: Announce the new feature.

* configure.ac (native-image-api): New option, OFF by default.
(HAVE_NATIVE_IMAGE_API): If native-image-api is selected, add
w32image.o to W32_OBJ.

1 files changed, 306 insertions, 0 deletions

diff --git a/src/w32image.c b/src/w32image.c
new file mode 100644
index 00000000000..fe32660f712
--- /dev/null
+++ b/src/w32image.c
@@ -0,0 +1,306 @@
+/* Implementation of MS-Windows native image API via the GDI+ library.
+
+Copyright (C) 2020 Free Software Foundation, Inc.
+
+This file is part of GNU Emacs.
+
+GNU Emacs is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or (at
+your option) any later version.
+
+GNU Emacs is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
+
+/* Written by Juan Jose Garcia-Ripoll <juanjose.garciaripoll@gmail.com>.  */
+
+#include <config.h>
+#include "lisp.h"
+#include "dispextern.h"
+#define COBJMACROS
+#include <objidl.h>
+#include <wtypes.h>
+#include <gdiplus.h>
+#include <shlwapi.h>
+#include "w32common.h"
+#include "w32term.h"
+#include "frame.h"
+#include "coding.h"
+
+/*#define LINK_GDIPLUS_STATICALLY 1*/
+
+#ifndef LINK_GDIPLUS_STATICALLY
+DEF_DLL_FN (GpStatus, GdiplusStartup, (ULONG_PTR *, GdiplusStartupInput *, GdiplusStartupOutput *));
+DEF_DLL_FN (VOID, GdiplusShutdown, (ULONG_PTR));
+DEF_DLL_FN (GpStatus, GdipGetPropertyItemSize, (GpImage *, PROPID, UINT *));
+DEF_DLL_FN (GpStatus, GdipGetPropertyItem, (GpImage *, PROPID, UINT, PropertyItem *));
+DEF_DLL_FN (GpStatus, GdipImageGetFrameDimensionsCount, (GpImage *, UINT *));
+DEF_DLL_FN (GpStatus, GdipImageGetFrameDimensionsList, (GpImage *, GUID *, UINT));
+DEF_DLL_FN (GpStatus, GdipImageGetFrameCount, (GpImage *, GDIPCONST GUID *, UINT *));
+DEF_DLL_FN (GpStatus, GdipImageSelectActiveFrame, (GpImage*, GDIPCONST GUID *, UINT));
+DEF_DLL_FN (GpStatus, GdipCreateBitmapFromFile, (WCHAR *, GpBitmap **));
+DEF_DLL_FN (GpStatus, GdipCreateBitmapFromStream, (IStream *, GpBitmap **));
+DEF_DLL_FN (IStream *, SHCreateMemStream, (const BYTE *pInit, UINT cbInit));
+DEF_DLL_FN (GpStatus, GdipCreateHBITMAPFromBitmap, (GpBitmap *, HBITMAP *, ARGB));
+DEF_DLL_FN (GpStatus, GdipDisposeImage, (GpImage *));
+DEF_DLL_FN (GpStatus, GdipGetImageHeight, (GpImage *, UINT *));
+DEF_DLL_FN (GpStatus, GdipGetImageWidth, (GpImage *, UINT *));
+#endif
+
+static int gdip_initialized = 0;
+static ULONG_PTR token;
+static GdiplusStartupInput input;
+static GdiplusStartupOutput output;
+
+bool
+w32_gdiplus_startup (void)
+{
+  HANDLE gdiplus_lib, shlwapi_lib;
+  GpStatus status;
+
+  if (gdip_initialized < 0)
+      return 0;
+  else if (gdip_initialized)
+      return 1;
+
+#ifndef LINK_GDIPLUS_STATICALLY
+  DEFSYM (Qgdiplus, "gdiplus");
+  DEFSYM (Qshlwapi, "shlwapi");
+  if (!(gdiplus_lib = w32_delayed_load (Qgdiplus))) {
+    gdip_initialized = -1;
+    return 0;
+  }
+  if (!(shlwapi_lib = w32_delayed_load (Qshlwapi))) {
+    gdip_initialized = -1;
+    return 0;
+  }
+
+  LOAD_DLL_FN (gdiplus_lib, GdiplusStartup);
+  LOAD_DLL_FN (gdiplus_lib, GdiplusShutdown);
+  LOAD_DLL_FN (gdiplus_lib, GdipGetPropertyItemSize);
+  LOAD_DLL_FN (gdiplus_lib, GdipGetPropertyItem);
+  LOAD_DLL_FN (gdiplus_lib, GdipImageGetFrameDimensionsCount);
+  LOAD_DLL_FN (gdiplus_lib, GdipImageGetFrameDimensionsList);
+  LOAD_DLL_FN (gdiplus_lib, GdipImageGetFrameCount);
+  LOAD_DLL_FN (gdiplus_lib, GdipImageSelectActiveFrame);
+  LOAD_DLL_FN (gdiplus_lib, GdipCreateBitmapFromFile);
+  LOAD_DLL_FN (gdiplus_lib, GdipCreateBitmapFromStream);
+  LOAD_DLL_FN (gdiplus_lib, GdipCreateHBITMAPFromBitmap);
+  LOAD_DLL_FN (gdiplus_lib, GdipDisposeImage);
+  LOAD_DLL_FN (gdiplus_lib, GdipGetImageHeight);
+  LOAD_DLL_FN (gdiplus_lib, GdipGetImageWidth);
+  LOAD_DLL_FN (shlwapi_lib, SHCreateMemStream);
+
+# define GdiplusStartup fn_GdiplusStartup
+# define GdiplusShutdown fn_GdiplusShutdown
+# define GdipGetPropertyItemSize fn_GdipGetPropertyItemSize
+# define GdipGetPropertyItem fn_GdipGetPropertyItem
+# define GdipImageGetFrameDimensionsCount fn_GdipImageGetFrameDimensionsCount
+# define GdipImageGetFrameDimensionsList fn_GdipImageGetFrameDimensionsList
+# define GdipImageGetFrameCount fn_GdipImageGetFrameCount
+# define GdipImageSelectActiveFrame fn_GdipImageSelectActiveFrame
+# define GdipCreateBitmapFromFile fn_GdipCreateBitmapFromFile
+# define GdipCreateBitmapFromStream fn_GdipCreateBitmapFromStream
+# define SHCreateMemStream fn_SHCreateMemStream
+# define GdipCreateHBITMAPFromBitmap fn_GdipCreateHBITMAPFromBitmap
+# define GdipDisposeImage fn_GdipDisposeImage
+# define GdipGetImageHeight fn_GdipGetImageHeight
+# define GdipGetImageWidth fn_GdipGetImageWidth
+#endif
+
+  input.GdiplusVersion = 1;
+  input.DebugEventCallback = NULL;
+  input.SuppressBackgroundThread = FALSE;
+  input.SuppressExternalCodecs = FALSE;
+
+  status = GdiplusStartup (&token, &input, &output);
+  if (status == Ok)
+    {
+      gdip_initialized = 1;
+      return 1;
+    }
+  else
+    {
+      gdip_initialized = -1;
+      return 0;
+    }
+}
+
+void
+w32_gdiplus_shutdown (void)
+{
+  GdiplusShutdown (token);
+}
+
+
+static double
+w32_frame_delay (GpBitmap *pBitmap, int frame)
+{
+  UINT size;
+  PropertyItem *propertyItem;
+  double delay = 0.0;
+
+  /* Assume that the image has a property item of type PropertyItemEquipMake.
+     Get the size of that property item.  */
+  GdipGetPropertyItemSize (pBitmap, PropertyTagFrameDelay, &size);
+
+  /* Allocate a buffer to receive the property item.  */
+  propertyItem = (PropertyItem*)malloc (size);
+  if (propertyItem != NULL)
+    {
+      /* Get the property item.  */
+      GdipGetPropertyItem (pBitmap, PropertyTagFrameDelay, size, propertyItem);
+      delay = ((double)propertyItem[frame].length) / 100;
+      if (delay == 0)
+        {
+          /* In GIF files, unfortunately, delay is only specified for the first
+             frame.  */
+          delay = ((double)propertyItem[0].length) / 100;
+        }
+      free (propertyItem);
+    }
+  return delay;
+}
+
+static UINT
+w32_select_active_frame (GpBitmap *pBitmap, int frame, int *nframes, double *delay)
+{
+  UINT count, frameCount;
+  GUID pDimensionIDs[1];
+  GpStatus status = Ok;
+
+  status = GdipImageGetFrameDimensionsCount (pBitmap, &count);
+  frameCount = *nframes = 0;
+  *delay = 0.0;
+  if (count)
+    {
+      status = GdipImageGetFrameDimensionsList (pBitmap, pDimensionIDs, 1);
+      status = GdipImageGetFrameCount (pBitmap, &pDimensionIDs[0], &frameCount);
+      if ((status == Ok) && (frameCount > 1))
+        {
+          if (frame < 0 || frame >= frameCount)
+            {
+              status = GenericError;
+            }
+          else
+            {
+              status = GdipImageSelectActiveFrame (pBitmap, &pDimensionIDs[0], frame);
+              *delay = w32_frame_delay (pBitmap, frame);
+              *nframes = frameCount;
+            }
+        }
+    }
+  return status;
+}
+
+static ARGB
+w32_image_bg_color (struct frame *f, struct image *img)
+{
+  /* png_color_16 *image_bg; */
+  Lisp_Object specified_bg
+    = Fplist_get (XCDR (img->spec), QCbackground);
+  Emacs_Color color;
+
+  /* If the user specified a color, try to use it; if not, use the
+     current frame background, ignoring any default background
+     color set by the image.  */
+  if (STRINGP (specified_bg)
+      ? w32_defined_color (f, SSDATA (specified_bg), &color, false, false)
+      : (w32_query_frame_background_color (f, &color), true))
+    /* The user specified `:background', use that.  */
+    {
+      DWORD red = (((DWORD) color.red) & 0xff00) << 8;
+      DWORD green = ((DWORD) color.green) & 0xff00;
+      DWORD blue = ((DWORD) color.blue) >> 8;
+      return red | green | blue;
+    }
+  return ((DWORD) 0xff000000);
+}
+
+int
+w32_load_image (struct frame *f, struct image *img,
+                Lisp_Object spec_file, Lisp_Object spec_data)
+{
+  Emacs_Pixmap pixmap;
+  GpStatus status = GenericError;
+  GpBitmap *pBitmap;
+  wchar_t filename[MAX_PATH];
+  ARGB bg_color;
+  Lisp_Object lisp_index, metadata;
+  unsigned int index, nframes;
+  double delay;
+
+  eassert (valid_image_p (img->spec));
+
+  /* This function only gets called if init_w32_gdiplus () was invoked. We have
+     a valid token and GDI+ is active.  */
+  if (STRINGP (spec_file))
+    {
+      if (w32_unicode_filenames)
+        {
+          filename_to_utf16 (SSDATA (spec_file) , filename);
+          status = GdipCreateBitmapFromFile (filename, &pBitmap);
+        }
+      else
+        {
+          add_to_log ("GDI+ requires w32-unicode-filenames to be T");
+          status = GenericError;
+        }
+    }
+  else if (STRINGP (spec_data))
+    {
+      IStream *pStream = SHCreateMemStream ((BYTE *) SSDATA (spec_data),
+                                            SBYTES (spec_data));
+      if (pStream != NULL)
+        {
+          status = GdipCreateBitmapFromStream (pStream, &pBitmap);
+          IStream_Release (pStream);
+        }
+    }
+
+  metadata = Qnil;
+  if (status == Ok)
+    {
+      /* In multiframe pictures, select the first one */
+      lisp_index = Fplist_get (XCDR (img->spec), QCindex);
+      index = FIXNUMP (lisp_index) ? XFIXNAT (lisp_index) : 0;
+      status = w32_select_active_frame (pBitmap, index, &nframes, &delay);
+      if ((status == Ok))
+        {
+          if (nframes > 1)
+            metadata = Fcons (Qcount, Fcons (make_fixnum (nframes), metadata));
+          if (delay)
+            metadata = Fcons (Qdelay, Fcons (make_float (delay), metadata));
+        }
+    }
+
+  if (status == Ok)
+    {
+      bg_color = w32_image_bg_color (f, img);
+      status = GdipCreateHBITMAPFromBitmap (pBitmap, &pixmap, bg_color);
+      if (status == Ok)
+        {
+          UINT width, height;
+          GdipGetImageWidth (pBitmap, &width);
+          GdipGetImageHeight (pBitmap, &height);
+          img->width = width;
+          img->height = height;
+          img->pixmap = pixmap;
+          img->lisp_data = metadata;
+        }
+
+      GdipDisposeImage (pBitmap);
+    }
+
+  if (status != Ok)
+    {
+      add_to_log ("Unable to load image %s", img->spec);
+      return 0;
+    }
+  return 1;
+}