Re: SVG support(again) ?

[joakim]

address@hidden writes:

> There was a patch for SVG support in Emacs in 2004.
> This patch seems to no longer apply.

I've adapted the SVG patch by Paul Pogonyshev for current emacs CVS.
All I did was find the right place to insert the hunks, since the
emacs source has changed a lot since the original patch.

I tried it briefly on a Fedora 7 box. It seems to work nicely.

What must be done in order for this patch to be applied?

The only odd thing I can see is three lines like:

#if 1 || defined (HAVE_RSVG)

that ought to be the same as:

#if defined (HAVE_RSVG)

which should be ok on any plattform, since HAVE_RSVG will be defined
only if you have librsvg2. I did try the configure script generated by
autoconf once withouth the lib and once with.

I tried making a SVG picture with Inkscape, viewing it in emacs using
image-dired, and then editing it a bit with nxml mode, and it seemed
to work nicely.

? emacs_svg.patch
Index: configure.in
===================================================================
RCS file: /sources/emacs/emacs/configure.in,v
retrieving revision 1.459
diff -r1.459 configure.in
112a113,114
> AC_ARG_WITH(rsvg,
> [  --with-rsvg             use -lrsvg-2 for displaying SVG images])
116c118
< [  --with-pkg-config-prog  Path to pkg-config to use for finding GTK])
---
> [  --with-pkg-config-prog  Path to pkg-config to use for finding GTK and 
> librsvg])
2124a2127,2152
> ### Use -lrsvg-2 if available, unless `--with-rsvg=no' is specified.
> HAVE_RSVG=no
> if test "${HAVE_X11}" = "yes"; then
>   if test "${with_rsvg}" != "no"; then
>     dnl Check if `--with-pkg-config-prog' has been given.
>     if test "X${with_pkg_config_prog}" != X; then
>       PKG_CONFIG="${with_pkg_config_prog}"
>     fi
> 
>     RSVG_REQUIRED=2.0.0
>     RSVG_MODULE="librsvg-2.0 >= $RSVG_REQUIRED"
> 
>     PKG_CHECK_MODULES(RSVG, $RSVG_MODULE, :, :)
>     AC_SUBST(RSVG_CFLAGS)
>     AC_SUBST(RSVG_LIBS)
> 
>     if test ".${RSVG_CFLAGS}" != "."; then
>       HAVE_RSVG=yes
>       AC_DEFINE(HAVE_RSVG, 1, [Define to 1 if using librsvg.])
>       CFLAGS="$CFLAGS $RSVG_CFLAGS"
>       LIBS="$RSVG_LIBS $LIBS"
>     fi
>   fi
> fi
> 
> 
3364a3393
> echo "  Does Emacs use -lrsvg-2?                                ${HAVE_RSVG}"
Index: lisp/image-file.el
===================================================================
RCS file: /sources/emacs/emacs/lisp/image-file.el,v
retrieving revision 1.29
diff -r1.29 image-file.el
42c42
<   '("png" "jpeg" "jpg" "gif" "tiff" "tif" "xbm" "xpm" "pbm" "pgm" "ppm" "pnm")
---
>   '("png" "jpeg" "jpg" "gif" "tiff" "tif" "xbm" "xpm" "pbm" "pgm" "ppm" "pnm" 
> "svg")
Index: lisp/image.el
===================================================================
RCS file: /sources/emacs/emacs/lisp/image.el,v
retrieving revision 1.72
diff -r1.72 image.el
46c46,47
<     ("\\`\xff\xd8" . (image-jpeg-p . jpeg)))
---
>     ("\\`\xff\xd8" . (image-jpeg-p . jpeg))
>     ("\\`<\\?xml " . svg))
Index: src/Makefile.in
===================================================================
RCS file: /sources/emacs/emacs/src/Makefile.in,v
retrieving revision 1.346
diff -r1.346 Makefile.in
284c284
< ALL_CFLAGS=-Demacs -DHAVE_CONFIG_H $(TOOLKIT_DEFINES) $(MYCPPFLAGS) -I. 
-I${srcdir} C_SWITCH_MACHINE C_SWITCH_SYSTEM C_SWITCH_SITE C_SWITCH_X_SITE 
C_SWITCH_X_MACHINE C_SWITCH_X_SYSTEM C_SWITCH_SYSTEM_TEMACS ${CFLAGS_SOUND} 
${CFLAGS}
---
> ALL_CFLAGS=-Demacs -DHAVE_CONFIG_H $(TOOLKIT_DEFINES) $(MYCPPFLAGS) -I. 
> -I${srcdir} C_SWITCH_MACHINE C_SWITCH_SYSTEM C_SWITCH_SITE @RSVG_CFLAGS@ 
> C_SWITCH_X_SITE C_SWITCH_X_MACHINE C_SWITCH_X_SYSTEM C_SWITCH_SYSTEM_TEMACS 
> ${CFLAGS_SOUND} ${CFLAGS}
453c453
< LIBX= $(LIBXMENU) $(X11_LDFLAGS) $(LIBXT) LIBTIFF LIBJPEG LIBPNG LIBGIF 
LIBXPM LIB_X11_LIB LIBX11_MACHINE LIBX11_SYSTEM $(XFT_LIBS)
---
> LIBX= $(LIBXMENU) $(X11_LDFLAGS) $(LIBXT) LIBTIFF LIBJPEG LIBPNG LIBGIF 
> LIBXPM @RSVG_LIBS@ LIB_X11_LIB LIBX11_MACHINE LIBX11_SYSTEM $(XFT_LIBS)
Index: src/image.c
===================================================================
RCS file: /sources/emacs/emacs/src/image.c,v
retrieving revision 1.77
diff -r1.77 image.c
8201a8202,8474
>  
> /***********************************************************************
>                                SVG
>  ***********************************************************************/
> 
> #if 1 || defined (HAVE_RSVG)
> 
> /* Function prototypes.  */
> 
> static int svg_image_p P_ ((Lisp_Object object));
> static int svg_load P_ ((struct frame *f, struct image *img));
> 
> static int svg_load_image P_ ((struct frame *, struct image *,
>                              unsigned char *, unsigned int));
> 
> /* The symbol `svg' identifying images of this type. */
> 
> Lisp_Object Qsvg;
> 
> /* Indices of image specification fields in svg_format, below.  */
> 
> enum svg_keyword_index
> {
>   SVG_TYPE,
>   SVG_DATA,
>   SVG_FILE,
>   SVG_ASCENT,
>   SVG_MARGIN,
>   SVG_RELIEF,
>   SVG_ALGORITHM,
>   SVG_HEURISTIC_MASK,
>   SVG_MASK,
>   SVG_BACKGROUND,
>   SVG_LAST
> };
> 
> /* Vector of image_keyword structures describing the format
>    of valid user-defined image specifications.  */
> 
> static struct image_keyword svg_format[SVG_LAST] =
> {
>   {":type",           IMAGE_SYMBOL_VALUE,                     1},
>   {":data",           IMAGE_STRING_VALUE,                     0},
>   {":file",           IMAGE_STRING_VALUE,                     0},
>   {":ascent",         IMAGE_ASCENT_VALUE,                     0},
>   {":margin",         IMAGE_POSITIVE_INTEGER_VALUE_OR_PAIR,   0},
>   {":relief",         IMAGE_INTEGER_VALUE,                    0},
>   {":conversion",     IMAGE_DONT_CHECK_VALUE_TYPE,            0},
>   {":heuristic-mask", IMAGE_DONT_CHECK_VALUE_TYPE,            0},
>   {":mask",           IMAGE_DONT_CHECK_VALUE_TYPE,            0},
>   {":background",     IMAGE_STRING_OR_NIL_VALUE,              0}
> };
> 
> /* Structure describing the image type `svg'.  */
> 
> static struct image_type svg_type =
> {
>   &Qsvg,
>   svg_image_p,
>   svg_load,
>   x_clear_image,
>   NULL
> };
> 
> 
> /* Return non-zero if OBJECT is a valid SVG image specification.  */
> 
> static int
> svg_image_p (object)
>      Lisp_Object object;
> {
>   struct image_keyword fmt[SVG_LAST];
>   bcopy (svg_format, fmt, sizeof fmt);
> 
>   if (!parse_image_spec (object, fmt, SVG_LAST, Qsvg))
>     return 0;
> 
>   /* Must specify either the :data or :file keyword.  */
>   return fmt[SVG_FILE].count + fmt[SVG_DATA].count == 1;
> }
> 
> #include <librsvg/rsvg.h>
> 
> /* DEF_IMGLIB_FN() here? */
> 
> #define fn_rsvg_handle_new            rsvg_handle_new
> #define fn_rsvg_handle_set_size_callback rsvg_handle_set_size_callback
> #define fn_rsvg_handle_write          rsvg_handle_write
> #define fn_rsvg_handle_close          rsvg_handle_close
> #define fn_rsvg_handle_get_pixbuf     rsvg_handle_get_pixbuf
> #define fn_rsvg_handle_free           rsvg_handle_free
> 
> #define fn_gdk_pixbuf_get_width               gdk_pixbuf_get_width
> #define fn_gdk_pixbuf_get_height      gdk_pixbuf_get_height
> #define fn_gdk_pixbuf_get_pixels      gdk_pixbuf_get_pixels
> #define fn_gdk_pixbuf_get_rowstride   gdk_pixbuf_get_rowstride
> #define fn_gdk_pixbuf_get_colorspace  gdk_pixbuf_get_colorspace
> #define fn_gdk_pixbuf_get_n_channels  gdk_pixbuf_get_n_channels
> #define fn_gdk_pixbuf_get_has_alpha   gdk_pixbuf_get_has_alpha
> #define fn_gdk_pixbuf_get_bits_per_sample gdk_pixbuf_get_bits_per_sample
> 
> 
> /* Load SVG image IMG for use on frame F.  Value is non-zero if
>    successful.  */
> 
> static int
> svg_load (f, img)
>      struct frame *f;
>      struct image *img;
> {
>   int success_p = 0;
>   Lisp_Object file_name;
> 
>   /* If IMG->spec specifies a file name, create a non-file spec from it.  */
>   file_name = image_spec_value (img->spec, QCfile, NULL);
>   if (STRINGP (file_name))
>     {
>       Lisp_Object file;
>       unsigned char *contents;
>       int size;
>       struct gcpro gcpro1;
> 
>       file = x_find_image_file (file_name);
>       GCPRO1 (file);
>       if (!STRINGP (file))
>       {
>         image_error ("Cannot find image file `%s'", file_name, Qnil);
>         UNGCPRO;
>         return 0;
>       }
> 
>       contents = slurp_file (SDATA (file), &size);
>       if (contents == NULL)
>       {
>         image_error ("Error loading SVG image `%s'", img->spec, Qnil);
>         UNGCPRO;
>         return 0;
>       }
> 
>       success_p = svg_load_image (f, img, contents, size);
>       xfree (contents);
>       UNGCPRO;
>     }
>   else
>     {
>       Lisp_Object data;
> 
>       data = image_spec_value (img->spec, QCdata, NULL);
>       success_p = svg_load_image (f, img, SDATA (data), SBYTES (data));
>     }
> 
>   return success_p;
> }
> 
> 
> static int
> svg_load_image (f, img, contents, size)
>      struct frame *f;
>      struct image *img;
>      unsigned char *contents;
>      unsigned int size;
> {
>   RsvgHandle *rsvg_handle;
>   GError *error = NULL;
>   GdkPixbuf *pixbuf;
>   int width;
>   int height;
>   const guint8 *pixels;
>   int rowstride;
>   XImagePtr ximg;
>   XColor background;
>   int x;
>   int y;
> 
>   g_type_init ();
>   rsvg_handle = fn_rsvg_handle_new ();
> 
>   fn_rsvg_handle_write (rsvg_handle, contents, size, &error);
>   if (error)
>     goto rsvg_error;
> 
>   fn_rsvg_handle_close (rsvg_handle, &error);
>   if (error)
>     goto rsvg_error;
> 
>   pixbuf = fn_rsvg_handle_get_pixbuf (rsvg_handle);
>   eassert (pixbuf);
> 
>   width     = fn_gdk_pixbuf_get_width (pixbuf);
>   height    = fn_gdk_pixbuf_get_height (pixbuf);
>   pixels    = fn_gdk_pixbuf_get_pixels (pixbuf);
>   rowstride = fn_gdk_pixbuf_get_rowstride (pixbuf);
> 
>   eassert (fn_gdk_pixbuf_get_colorspace (pixbuf) == GDK_COLORSPACE_RGB);
>   eassert (fn_gdk_pixbuf_get_n_channels (pixbuf) == 4);
>   eassert (fn_gdk_pixbuf_get_has_alpha (pixbuf));
>   eassert (fn_gdk_pixbuf_get_bits_per_sample (pixbuf) == 8);
> 
>   if (!x_create_x_image_and_pixmap (f, width, height, 0, &ximg, 
> &img->pixmap)) {
>     g_object_unref (pixbuf);
>     return 0;
>   }
> 
>   init_color_table ();
> 
> #ifdef HAVE_X_WINDOWS
> 
>   background.pixel = FRAME_BACKGROUND_PIXEL (f);
>   x_query_color (f, &background);
> 
>   background.red   >>= 8;
>   background.green >>= 8;
>   background.blue  >>= 8;
> 
> #else /* not HAVE_X_WINDOWS */
> #error FIXME
> #endif
> 
>   for (y = 0; y < height; ++y)
>     {
>       for (x = 0; x < width; ++x)
>       {
>         unsigned red;
>         unsigned green;
>         unsigned blue;
>         unsigned opacity;
> 
>         red     = *pixels++;
>         green   = *pixels++;
>         blue    = *pixels++;
>         opacity = *pixels++;
> 
>         red   = ((red * opacity)
>                  + (background.red * ((1 << 8) - opacity)));
>         green = ((green * opacity)
>                  + (background.green * ((1 << 8) - opacity)));
>         blue  = ((blue * opacity)
>                  + (background.blue * ((1 << 8) - opacity)));
> 
>         XPutPixel (ximg, x, y, lookup_rgb_color (f, red, green, blue));
>       }
> 
>       pixels += rowstride - 4 * width;
>     }
> 
> #ifdef COLOR_TABLE_SUPPORT
>   /* Remember colors allocated for this image.  */
>   img->colors = colors_in_color_table (&img->ncolors);
>   free_color_table ();
> #endif /* COLOR_TABLE_SUPPORT */
> 
>   g_object_unref (pixbuf);
> 
>   /* Put the image into the pixmap, then free the X image and its buffer. */
>   x_put_x_image (f, ximg, img->pixmap, width, height);
>   x_destroy_x_image (ximg);
> 
>   img->width  = width;
>   img->height = height;
> 
>   return 1;
> 
>  rsvg_error:
>   /* FIXME: Use error->message. */
>   image_error ("Error parsing SVG image `%s'", img->spec, Qnil);
>   g_error_free (error);
>   return 0;
> }
> 
> #endif        /* defined (HAVE_RSVG) */
> 
> 
> 
8593a8867,8871
> #if 1 || defined (HAVE_RSVG)
>   if (EQ (type, Qsvg))
>     return CHECK_LIB_AVAILABLE (&svg_type, init_svg_functions, libraries);
> #endif
>   
8735a9014,9020
> #if 1 || defined (HAVE_RSVG)
>   Qsvg = intern ("svg");
>   staticpro (&Qsvg);
>   ADD_IMAGE_TYPE(Qsvg);
> #endif
> 
>   

>
> Has anyone adopted it for the current tree? If so, coculd it be
> applied?
>
> -- 
> Joakim Verona

-- 
Joakim Verona