add framework for an svg:cairo loadimage plugin using librsvg2

diff --git a/plugin/rsvg/Makefile.am b/plugin/rsvg/Makefile.am
new file mode 100644 (file)
index 0000000..ad6bae0
--- /dev/null
+++ b/plugin/rsvg/Makefile.am
@@ -0,0 +1,28 @@
+# $Id$ $Revision$
+## Process this file with automake to produce Makefile.in
+
+AM_CPPFLAGS = \
+       -I$(top_srcdir) \
+       -I$(top_srcdir)/lib/common \
+       -I$(top_srcdir)/lib/pathplan \
+       -I$(top_srcdir)/lib/gvc \
+       -I$(top_srcdir)/lib/graph \
+       -I$(top_srcdir)/lib/cdt \
+       $(RSVG_CFLAGS) $(PANGOCAIRO_CFLAGS)
+
+if WITH_RSVG
+noinst_LTLIBRARIES = libgvplugin_rsvg_C.la
+pkglib_LTLIBRARIES = libgvplugin_rsvg.la
+endif
+
+libgvplugin_rsvg_C_la_SOURCES = \
+       gvplugin_rsvg.c \
+       gvloadimage_rsvg.c
+
+libgvplugin_rsvg_la_LDFLAGS = -version-info @GVPLUGIN_VERSION_INFO@
+libgvplugin_rsvg_la_SOURCES = $(libgvplugin_rsvg_C_la_SOURCES)
+libgvplugin_rsvg_la_LIBADD = \
+       $(top_builddir)/lib/gvc/libgvc.la @RSVG_LIBS@ @PANGOCAIRO_LIBS@
+
+EXTRA_DIST = Makefile.old
+

diff --git a/plugin/rsvg/gvloadimage_rsvg.c b/plugin/rsvg/gvloadimage_rsvg.c
new file mode 100644 (file)
index 0000000..17164eb
--- /dev/null
+++ b/plugin/rsvg/gvloadimage_rsvg.c
@@ -0,0 +1,115 @@
+/* $Id$ $Revision$ */
+/* vim:set shiftwidth=4 ts=8: */
+
+/**********************************************************
+*      This software is part of the graphviz package      *
+*                http://www.graphviz.org/                 *
+*                                                         *
+*            Copyright (c) 1994-2004 AT&T Corp.           *
+*                and is licensed under the                *
+*            Common Public License, Version 1.0           *
+*                      by AT&T Corp.                      *
+*                                                         *
+*        Information and Software Systems Research        *
+*              AT&T Research, Florham Park NJ             *
+**********************************************************/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdlib.h>
+
+#include "gvplugin_loadimage.h"
+
+#ifdef HAVE_PANGOCAIRO
+#ifdef HAVE_RSVG
+#include <librsvg/rsvg.h>
+#include <librsvg/rsvg-cairo.h>
+
+typedef enum {
+    FORMAT_SVG_CAIRO,
+} format_type;
+
+static cairo_status_t
+reader (void *closure, unsigned char *data, unsigned int length)
+{
+    if (length == fread(data, 1, length, (FILE *)closure)
+     || feof((FILE *)closure))
+        return CAIRO_STATUS_SUCCESS;
+    return CAIRO_STATUS_READ_ERROR;
+}
+
+static void cairo_freeimage(usershape_t *us)
+{
+    cairo_destroy((cairo_t*)us->data);
+}
+
+static cairo_surface_t* cairo_loadimage(GVJ_t * job, usershape_t *us)
+{
+    cairo_surface_t *surface = NULL; /* source surface */
+
+    assert(job);
+    assert(us);
+    assert(us->name);
+    assert(us->f);
+
+    if (us->data) {
+        if (us->datafree == cairo_freeimage)
+             surface = (cairo_surface_t*)(us->data); /* use cached data */
+        else {
+             us->datafree(us);        /* free incompatible cache data */
+             us->data = NULL;
+        }
+    }
+    if (!surface) { /* read file into cache */
+        fseek(us->f, 0, SEEK_SET);
+        switch (us->type) {
+#ifdef CAIRO_HAS_PNG_FUNCTIONS
+            case FT_PNG:
+                surface = cairo_image_surface_create_from_png_stream(reader, us->f);
+                cairo_surface_reference(surface);
+                break;
+#endif
+            default:
+                surface = NULL;
+        }
+        if (surface) {
+            us->data = (void*)surface;
+            us->datafree = cairo_freeimage;
+        }
+    }
+    return surface;
+}
+
+static void rsvg_loadimage_cairo(GVJ_t * job, usershape_t *us, boxf b, boolean filled)
+{
+    cairo_t *cr = (cairo_t *) job->context; /* target context */
+    cairo_surface_t *surface;   /* source surface */
+
+    surface = cairo_loadimage(job, us);
+    if (surface) {
+        cairo_save(cr);
+        cairo_translate(cr, ROUND(b.LL.x), ROUND(-b.UR.y));
+        cairo_scale(cr, (b.UR.x - b.LL.x) / us->w,
+                        (b.UR.y - b.LL.y) / us->h);
+        cairo_set_source_surface (cr, surface, 0, 0);
+        cairo_paint (cr);
+        cairo_restore(cr);
+    }
+}
+
+static gvloadimage_engine_t engine_cairo = {
+    rsvg_loadimage_cairo
+};
+#endif
+#endif
+
+gvplugin_installed_t gvloadimage_rsvg_types[] = {
+#ifdef HAVE_PANGOCAIRO
+#ifdef HAVE_RSVG
+    {FORMAT_SVG_CAIRO, "svg:cairo", 1, &engine_cairo, NULL},
+#endif
+#endif
+    {0, NULL, 0, NULL, NULL}
+};