[lasem] render: allows to give an element to render

[Emmanuel Pacaud <emmanuel src gnome org>]

commit 449c86f8ae73b272a2b70d64b3f3a1b329cd20da
Author: Emmanuel Pacaud <emmanuel gnome org>
Date:   Tue Jun 28 20:55:51 2016 +0200

    render: allows to give an element to render
    
    Only SVG is supported for now. It only hides other elements and doesn't
    affect the rendered image size.

 src/lasemrender.c |   48 +++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 47 insertions(+), 1 deletions(-)
---
diff --git a/src/lasemrender.c b/src/lasemrender.c
index de2ca2f..f797277 100644
--- a/src/lasemrender.c
+++ b/src/lasemrender.c
@@ -25,6 +25,7 @@
 #include <stdlib.h>
 #include <lsm.h>
 #include <lsmmathml.h>
+#include <lsmsvg.h>
 #include <glib.h>
 #include <glib/gi18n.h>
 #include <gio/gio.h>
@@ -39,6 +40,7 @@ static char *option_debug_domains = NULL;
 static char *option_output_file_format = NULL;
 static char **option_input_filenames = NULL;
 static char *option_output_filename = NULL;
+static char *option_element_id = NULL;
 double option_ppi = 72.0;
 double option_zoom = 1.0;
 
@@ -70,12 +72,49 @@ static const GOptionEntry entries[] =
                &option_ppi,                    N_("Pixel per inch"), NULL },
        { "zoom",               'z', 0, G_OPTION_ARG_DOUBLE,
                &option_zoom,                   N_("Zoom"), NULL },
+       { "id",                 'i', 0, G_OPTION_ARG_STRING,
+               &option_element_id,             N_("Element id"), NULL },
        { "debug",              'd', 0, G_OPTION_ARG_STRING,
                &option_debug_domains,          N_("Debug domains"), NULL },
        { NULL }
 };
 
-int main(int argc, char **argv)
+static gboolean
+_hide_before_object (LsmDomDocument *document, const char *id)
+{
+       LsmDomNode *node;
+       LsmDomNode *sibling;
+       LsmDomNode *parent;
+
+       /* TODO: Handle other document types */
+       if (!LSM_IS_SVG_DOCUMENT (document)) {
+               fprintf (stderr, "%s\n", _("Invalid document type (SVG expected)"));
+               return  FALSE;
+       }
+
+       node = LSM_DOM_NODE (lsm_svg_document_get_element_by_id (LSM_SVG_DOCUMENT (document), id));
+       if (!LSM_IS_DOM_NODE (node)) {
+               fprintf (stderr, _("Element '%s' not found"), id);
+               fprintf (stderr, "\n");
+               return FALSE;
+       }
+
+       for (parent = lsm_dom_node_get_parent_node (node);
+            LSM_IS_DOM_NODE (parent);
+            node = parent, parent = lsm_dom_node_get_parent_node (parent)) {
+               for (sibling = lsm_dom_node_get_first_child (parent);
+                    LSM_IS_DOM_NODE (sibling);
+                    sibling = lsm_dom_node_get_next_sibling (sibling)) {
+                       if (sibling != node && LSM_IS_SVG_ELEMENT (sibling))
+                               lsm_dom_element_set_attribute (LSM_DOM_ELEMENT (sibling), "display", "none");
+               }
+       }
+
+       return TRUE;
+}
+
+int
+main(int argc, char **argv)
 {
        LsmDomDocument *document;
        LsmDomView *view;
@@ -187,6 +226,13 @@ int main(int argc, char **argv)
                }
        }
 
+       if (document != NULL && option_element_id != NULL) {
+               if (!_hide_before_object (document, option_element_id)) {
+                       g_object_unref (document);
+                       return EXIT_FAILURE;
+               }
+       }
+
        if (document != NULL) {
                if (lsm_debug_check (&lsm_debug_category_dom, LSM_DEBUG_LEVEL_LOG)) {
                        void *buffer;