Struct

GskRenderReplay

unstable since: 4.22

Description [src]

struct GskRenderReplay {
  /* No available fields */
}

A facility to replay a GskRenderNode and its children, potentially modifying them.

This is a utility tool to walk a rendernode tree. The most powerful way is to provide a function via gsk_render_replay_set_node_filter() to filter each individual node and then run gsk_render_replay_filter_node() on the nodes you want to filter.

An easier method exists to just walk the node tree and extract information without any modifications. If you want to do that, the functions gsk_render_replay_set_node_foreach() exists. You can also call gsk_render_replay_foreach_node() to run that function. Note that the previously mentioned complex functionality will still be invoked if you have set up a function for it, but its result will not be returned.

Here is an example that combines both approaches to print the whole tree:

#include <gtk/gtk.h>

static GskRenderNode *
print_nodes (GskRenderReplay *replay,
             GskRenderNode   *node,
             gpointer         user_data)
{
  int *depth = user_data;
  GskRenderNode *result;

  g_print ("%*s%s\n", 2 * *depth, "", g_type_name_from_instance ((GTypeInstance *) node));

  *depth += 1;
  result = gsk_render_replay_default (replay, node);
  *depth -= 1;

  return result;
}

int
main (int argc, char *argv[])
{
  GFile *file;
  GBytes *bytes;
  GskRenderNode *node;
  GskRenderReplay *replay;
  int depth = 0;

  gtk_init ();

  if (argc < 2)
    {
      g_print ("usage: %s NODEFILE\n", argv[0]);
      return 0;
    }

  file = g_file_new_for_commandline_arg (argv[1]);
  bytes = g_file_load_bytes (file, NULL, NULL, NULL);
  g_object_unref (file);
  if (bytes == NULL)
    return 1;

  node = gsk_render_node_deserialize (bytes, NULL, NULL);
  g_bytes_unref (bytes);
  if (node == NULL)
    return 1;

  replay = gsk_render_replay_new ();
  gsk_render_replay_set_node_filter (replay, print_nodes, &depth, NULL);
  gsk_render_node_foreach_node (replay, node);
  gsk_render_node_unref (node);

  return 0;
}