From: Emmanuel Rodriguez Date: Wed, 15 Apr 2009 18:30:35 +0000 (+0200) Subject: Firt version of the demo that downloads an image X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=828937764879410cba6425f509edee379c7cad2d;p=libchamplain Firt version of the demo that downloads an image --- diff --git a/demos/image.c b/demos/image.c new file mode 100644 index 0000000..47e10c7 --- /dev/null +++ b/demos/image.c @@ -0,0 +1,214 @@ +/* + * Copyright (C) 2009 Emmanuel Rodriguez + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include +#include +#include + + +/** + * Transforms a pixbuf into a Clutter texture. + */ +static ClutterActor* +pixbuf_to_texture (GdkPixbuf *pixbuf, GError **error) +{ + ClutterActor *texture = NULL; + const guchar *data; + gboolean has_alpha, success; + int width, height, rowstride; + ClutterTextureFlags flags = 0; + + data = gdk_pixbuf_get_pixels (pixbuf); + width = gdk_pixbuf_get_width (pixbuf); + height = gdk_pixbuf_get_height (pixbuf); + has_alpha = gdk_pixbuf_get_has_alpha (pixbuf); + rowstride = gdk_pixbuf_get_rowstride (pixbuf); + + texture = clutter_texture_new (); + success = clutter_texture_set_from_rgb_data (CLUTTER_TEXTURE (texture), + data, + has_alpha, + width, + height, + rowstride, + (has_alpha ? 4 : 3), + flags, + error); + if (! success) { + g_print ("Failed to create the texture\n"); + clutter_actor_destroy (CLUTTER_ACTOR (texture)); + return NULL; + } + + g_print ("Created the texture\n"); + return texture; +} + + +/** + * Called when an image has been downloaded. This callback will transform the + * image data (binary chunk sent by the remote web server) into a valid Clutter + * actor (a texture) and will use this as the source image for a new marker. The + * marker will then be added to an existing layer. + * + * This callback expects the parameter data to be a valid ChamplainLayer. + */ +static void +image_downloaded_cb (SoupSession *session, + SoupMessage *message, + gpointer data) +{ + ChamplainLayer *layer = NULL; + SoupURI *uri = NULL; + char *url = NULL; + const gchar *mime_type = NULL; + GdkPixbufLoader *loader = NULL; + GError *error = NULL; + GdkPixbuf *pixbuf = NULL; + ClutterActor *texture = NULL; + ClutterActor *marker = NULL; + + g_print("Downloaded the image\n"); + if (data == NULL) { + g_print ("Missing the data pointer\n"); + goto cleanup; + } + + /* Deal only with finished messages */ + g_print ("message->status_code = %d\n", message->status_code); + if (! SOUP_STATUS_IS_SUCCESSFUL(message->status_code)) { + g_print ("SOUP message isn't finished\n"); + goto cleanup; + } + + uri = soup_message_get_uri (message); + url = soup_uri_to_string (uri, FALSE); + + /* Deal only with successful messages */ + if (! SOUP_STATUS_IS_SUCCESSFUL (message->status_code)) { + g_print ("Skipping download of %s since server returned error code %d\n", url, message->status_code); + goto cleanup; + } + + /* Make sure that we downloaded an image */ + mime_type = soup_message_headers_get (message->response_headers, "Content-Type"); + + + /* First transform the image into a pixbuf */ + loader = gdk_pixbuf_loader_new_with_mime_type (mime_type, &error); + if (error) { + g_print ("Can't build a PixbufLoader that will parse a %s image %s\n", mime_type, error->message); + if (loader) {gdk_pixbuf_loader_close (loader, NULL);} + goto cleanup; + } + gdk_pixbuf_loader_write ( + loader, + message->response_body->data, + message->response_body->length, + &error); + if (error) { + g_print ("Can't parse the image %s: %s\n", url, error->message); + gdk_pixbuf_loader_close (loader, NULL); + goto cleanup; + } + + gdk_pixbuf_loader_close (loader, &error); + if (error) { + g_print ("Can't close the parser for image %s: %s\n", url, error->message); + goto cleanup; + } + pixbuf = gdk_pixbuf_loader_get_pixbuf (loader); + if (pixbuf == NULL) { + goto cleanup; + } + g_print ("Got a pixbuf\n"); + + /* Then transform the pixbuf into a texture */ + texture = pixbuf_to_texture (pixbuf, &error); + if (error) { + g_print ("Can't convert the pixbuf into a texture for image %s: %s\n", url, error->message); + goto cleanup; + } + g_print ("Got a texture\n"); + + /* Finally create a marker with the texture */ + layer = CHAMPLAIN_LAYER (data); + marker = champlain_marker_new_with_image (texture); + texture = NULL; + champlain_base_marker_set_position (CHAMPLAIN_BASE_MARKER (marker), 45.466, -73.75); + clutter_container_add (CLUTTER_CONTAINER (layer), marker, NULL); + clutter_actor_show_all (marker); + + /* Cleanup part, the function will always exit here even in case of error */ + cleanup: + g_free (url); + if (loader) {g_object_unref (G_OBJECT (loader));} + if (texture) {clutter_actor_destroy (CLUTTER_ACTOR (texture));} + return; +} + + +static void +create_marker_from_url (ChamplainLayer *layer, + SoupSession *session, + const gchar *url) +{ + SoupMessage *message; + + message = soup_message_new ("GET", url); + soup_session_queue_message (session, message, image_downloaded_cb, layer); + g_print ("Downloading %s\n", url); +} + + +int +main (int argc, char *argv[]) +{ + ClutterActor* actor, *stage; + ChamplainLayer *layer; + SoupSession *session; + + g_thread_init (NULL); + clutter_init (&argc, &argv); + + stage = clutter_stage_get_default (); + clutter_actor_set_size (stage, 800, 600); + + /* Create the map view */ + actor = champlain_view_new (); + champlain_view_set_size (CHAMPLAIN_VIEW (actor), 800, 600); + clutter_container_add_actor (CLUTTER_CONTAINER (stage), actor); + + /* Create the markers and marker layer */ + layer = champlain_layer_new (); + champlain_view_add_layer (CHAMPLAIN_VIEW (actor), layer); + session = soup_session_async_new (); + create_marker_from_url (layer, session, "http://hexten.net/cpan-faces/potyl.jpg"); + + /* Finish initialising the map view */ + g_object_set (G_OBJECT (actor), "zoom-level", 12, + "scroll-mode", CHAMPLAIN_SCROLL_MODE_KINETIC, NULL); + champlain_view_center_on (CHAMPLAIN_VIEW(actor), 45.466, -73.75); + + clutter_actor_show (stage); + clutter_main (); + + g_object_unref (session); + + return 0; +}