Fix:gui_internal:More functionality for gui_internal

git-svn-id: http://svn.code.sf.net/p/navit/code/trunk/navit@1125 ffa7fe5e-494d-0410-b361-a75ebd5db220

6 files changed, 356 insertions, 39 deletions

diff --git a/navit/gui/internal/gui_internal.c b/navit/gui/internal/gui_internal.c
index a28b71241..6662c9331 100644
--- a/navit/gui/internal/gui_internal.c
+++ b/navit/gui/internal/gui_internal.c
@@ -45,6 +45,9 @@
 #include "transform.h"
 #include "color.h"
 #include "map.h"
+#include "layout.h"
+#include "callback.h"
+#include "vehicle.h"
 #include "config.h"
 
 #define STATE_VISIBLE 1
@@ -98,13 +101,22 @@ struct widget {
 	void *data;
 	char *prefix;
 	char *name;
-	struct coord c;
+	struct pcoord c;
 	int state;
 	struct point p;
 	int wmin,hmin;
 	int w,h;
 	int bl,br,bt,bb,spx,spy;
 	enum flags flags;
+	void *instance;
+	int (*set_attr)(void *, struct attr *);
+	int (*get_attr)(void *, enum attr_type, struct attr *, struct attr_iter *);
+	void (*remove_cb)(void *, struct callback *cb);
+	struct callback *cb;
+	struct attr on;
+	struct attr off;
+	int is_on;
+	int redraw;
 	GList *children;
 };
 
@@ -127,6 +139,7 @@ struct gui_priv {
 	int pressed;
 	struct widget *widgets;
 	int widgets_count;
+	int redraw;
 	struct widget root;
 	struct widget *highlighted;
 	struct widget *highlighted_menu;
@@ -181,7 +194,7 @@ image_new_scaled(struct gui_priv *this, char *name, int w, int h)
 }
 
 static struct graphics_image *
-image_new(struct gui_priv *this, char *name)
+image_new_o(struct gui_priv *this, char *name)
 {
 	return image_new_scaled(this, name, -1, -1);
 }
@@ -221,7 +234,6 @@ gui_internal_label_new(struct gui_priv *this, char *text)
 {
 	struct point p[4];
 	int h=this->font_size;
-	char *pos=text;
 
 	struct widget *widget=g_new0(struct widget, 1);
 	widget->type=widget_label;
@@ -332,6 +344,92 @@ gui_internal_button_new_with_callback(struct gui_priv *this, char *text, struct
 
 }
 
+static int
+gui_internal_button_attr_update(struct gui_priv *this, struct widget *w)
+{
+	struct widget *wi;
+	int is_on=0;
+	struct attr curr;
+
+	if (w->get_attr(w->instance, w->on.type, &curr, NULL))
+		is_on=curr.u.data == w->on.u.data;
+	if (is_on != w->is_on) {
+		if (w->redraw)
+			this->redraw=1;
+		w->is_on=is_on;
+		wi=g_list_first(w->children)->data;
+		if (wi->img)
+			graphics_image_free(this->gra, wi->img);
+		wi->img=image_new_xs(this, is_on ? "gui_active" : "gui_inactive");
+		if (w->is_on && w->off.type == attr_none)
+			w->state &= ~STATE_SENSITIVE;
+		else
+			w->state |= STATE_SENSITIVE;
+		return 1;
+	}
+	return 0;
+}
+
+static void
+gui_internal_button_attr_callback(struct gui_priv *this, struct widget *w)
+{
+	dbg(0,"enter\n");
+	if (gui_internal_button_attr_update(this, w))
+		gui_internal_widget_render(this, w);
+}
+static void
+gui_internal_button_attr_pressed(struct gui_priv *this, struct widget *w)
+{
+	dbg(0,"enter is_on=%d\n", w->is_on);
+	if (w->is_on) 
+		w->set_attr(w->instance, &w->off);
+	else
+		w->set_attr(w->instance, &w->on);
+	gui_internal_button_attr_update(this, w);
+	
+}
+
+static struct widget *
+gui_internal_button_navit_attr_new(struct gui_priv *this, char *text, enum flags flags, struct attr *on, struct attr *off)
+{
+	struct graphics_image *image=image_new_xs(this, "gui_inactive");
+	struct widget *ret;
+	ret=gui_internal_button_new_with_callback(this, text, image, flags, gui_internal_button_attr_pressed, NULL);
+	if (on)
+		ret->on=*on;
+	if (off)
+		ret->off=*off;
+	ret->get_attr=navit_get_attr;
+	ret->set_attr=navit_set_attr;
+	ret->remove_cb=navit_remove_callback;
+	ret->instance=this->nav;
+	ret->cb=callback_new_attr_2(gui_internal_button_attr_callback, on->type, this, ret);
+	navit_add_callback(this->nav, ret->cb);
+	gui_internal_button_attr_update(this, ret);
+	return ret;
+}
+
+static struct widget *
+gui_internal_button_map_attr_new(struct gui_priv *this, char *text, enum flags flags, struct map *map, struct attr *on, struct attr *off)
+{
+	struct graphics_image *image=image_new_xs(this, "gui_inactive");
+	struct widget *ret;
+	ret=gui_internal_button_new_with_callback(this, text, image, flags, gui_internal_button_attr_pressed, NULL);
+	if (on)
+		ret->on=*on;
+	if (off)
+		ret->off=*off;
+	ret->get_attr=map_get_attr;
+	ret->set_attr=map_set_attr;
+	ret->remove_cb=map_remove_callback;
+	ret->instance=map;
+	ret->redraw=1;
+	ret->cb=callback_new_attr_2(gui_internal_button_attr_callback, on->type, this, ret);
+	map_add_callback(map, ret->cb);
+	gui_internal_button_attr_update(this, ret);
+	return ret;
+}
+
 static struct widget *
 gui_internal_button_new(struct gui_priv *this, char *text, struct graphics_image *image, enum flags flags)
 {
@@ -595,6 +693,8 @@ static void gui_internal_widget_destroy(struct gui_priv *this, struct widget *w)
 		g_free(w->prefix);
 	if (w->name)
 		g_free(w->name);
+	if (w->cb && w->remove_cb)
+		w->remove_cb(w->instance, w->cb);
 	g_free(w);
 }
 
@@ -797,25 +897,11 @@ gui_internal_menu_render(struct gui_priv *this)
 }
 
 static void
-gui_internal_cmd_rules(struct gui_priv *this, struct widget *wm)
+gui_internal_cmd_set_destination(struct gui_priv *this, struct widget *wm)
 {
-	struct widget *wb,*w;
-	wb=gui_internal_menu(this, "Rules");	
-	w=gui_internal_box_new(this, gravity_top_center|orientation_vertical|flags_expand|flags_fill);
-	gui_internal_widget_append(wb, w);
-	gui_internal_widget_append(w,
-		gui_internal_button_new(this, "Stick to roads, obey traffic rules",
-			image_new(this, "gui_active"), gravity_left_center|orientation_horizontal|flags_fill));
-	gui_internal_widget_append(w,
-		gui_internal_button_new(this, "Keep orientation to the North",
-			image_new(this, "gui_active"), gravity_left_center|orientation_horizontal|flags_fill));
-	gui_internal_widget_append(w,
-		gui_internal_button_new(this, "Warn about wrong directions",
-			image_new(this, "gui_inactive"), gravity_left_center|orientation_horizontal|flags_fill));
-	gui_internal_widget_append(w,
-		gui_internal_button_new(this, "Attack defenseless civilians",
-			image_new(this, "gui_active"), gravity_left_center|orientation_horizontal|flags_fill));
-	gui_internal_menu_render(this);
+	struct widget *w=wm->data;
+	navit_set_destination(this->nav, &w->c, w->name);
+	gui_internal_prune_menu(this, NULL);
 }
 
 static void
@@ -826,30 +912,34 @@ gui_internal_cmd_position(struct gui_priv *this, struct widget *wm)
 	w=gui_internal_box_new(this, gravity_top_center|orientation_vertical|flags_expand|flags_fill);
 	gui_internal_widget_append(wb, w);
 	gui_internal_widget_append(w,
-		gui_internal_button_new(this, "Set as destination",
-			image_new(this, "gui_active"), gravity_left_center|orientation_horizontal|flags_fill));
+		gui_internal_button_new_with_callback(this, "Set as destination",
+			image_new_xs(this, "gui_active"), gravity_left_center|orientation_horizontal|flags_fill,
+			gui_internal_cmd_set_destination, wm));
+#if 0
 	gui_internal_widget_append(w,
 		gui_internal_button_new(this, "Add to tour",
-			image_new(this, "gui_active"), gravity_left_center|orientation_horizontal|flags_fill));
+			image_new_o(this, "gui_active"), gravity_left_center|orientation_horizontal|flags_fill));
 	gui_internal_widget_append(w,
 		gui_internal_button_new(this, "Add as bookmark",
-			image_new(this, "gui_active"), gravity_left_center|orientation_horizontal|flags_fill));
+			image_new_o(this, "gui_active"), gravity_left_center|orientation_horizontal|flags_fill));
 	gui_internal_widget_append(w,
 		gui_internal_button_new(this, "View on map",
-			image_new(this, "gui_active"), gravity_left_center|orientation_horizontal|flags_fill));
+			image_new_o(this, "gui_active"), gravity_left_center|orientation_horizontal|flags_fill));
+#endif
 	gui_internal_menu_render(this);
 }
 
 static void
 gui_internal_cmd_bookmarks(struct gui_priv *this, struct widget *wm)
 {
-	struct attr attr;
+	struct attr attr,mattr;
 	struct map_rect *mr=NULL;
 	struct item *item;
 	char *label_full,*l,*prefix,*pos;
 	int len,plen,hassub;
 	struct widget *wb,*w,*wbm;
 	GHashTable *hash;
+	struct coord c;
 
 
 	wb=gui_internal_menu(this, wm->text ? wm->text : "Bookmarks");
@@ -861,7 +951,7 @@ gui_internal_cmd_bookmarks(struct gui_priv *this, struct widget *wm)
 		prefix="";
 	plen=strlen(prefix);
 
-	if(navit_get_attr(this->nav, attr_bookmark_map, &attr, NULL) && attr.u.map && (mr=map_rect_new(attr.u.map, NULL))) {
+	if(navit_get_attr(this->nav, attr_bookmark_map, &mattr, NULL) && mattr.u.map && (mr=map_rect_new(mattr.u.map, NULL))) {
 		hash=g_hash_table_new_full(g_str_hash, g_str_equal, g_free, NULL);
 		while ((item=map_rect_get_item(mr))) {
 			if (item->type != type_bookmark) continue;
@@ -883,8 +973,11 @@ gui_internal_cmd_bookmarks(struct gui_priv *this, struct widget *wm)
 					wbm=gui_internal_button_new_with_callback(this, l,
 						image_new_xs(this, hassub ? "gui_inactive" : "gui_active" ), gravity_left_center|orientation_horizontal|flags_fill,
 							hassub ? gui_internal_cmd_bookmarks : gui_internal_cmd_position, NULL);
-					if (item_coord_get(item, &wbm->c, 1)) {
-						wbm->name=g_strdup(label_full);
+					if (item_coord_get(item, &c, 1)) {
+						wbm->c.x=c.x;
+						wbm->c.y=c.y;
+						wbm->c.pro=map_projection(mattr.u.map);
+						wbm->name=g_strdup_printf("Bookmark %s",label_full);
 						wbm->text=g_strdup(l);
 						gui_internal_widget_append(w, wbm);
 						g_hash_table_insert(hash, g_strdup(l), (void *)1);
@@ -905,6 +998,42 @@ gui_internal_cmd_bookmarks(struct gui_priv *this, struct widget *wm)
 }
 
 static void
+gui_internal_cmd_layout(struct gui_priv *this, struct widget *wm)
+{
+	struct attr attr;
+	struct widget *w,*wb,*wl;
+	struct attr_iter *iter;
+
+
+	wb=gui_internal_menu(this, "Layout");
+	w=gui_internal_box_new(this, gravity_top_center|orientation_vertical|flags_expand|flags_fill);
+	gui_internal_widget_append(wb, w);
+	iter=navit_attr_iter_new();
+	while(navit_get_attr(this->nav, attr_layout, &attr, iter)) {
+		wl=gui_internal_button_navit_attr_new(this, attr.u.layout->name, gravity_left_center|orientation_horizontal|flags_fill,
+			&attr, NULL);
+		gui_internal_widget_append(w, wl);
+	}
+	navit_attr_iter_destroy(iter);
+	gui_internal_menu_render(this);
+}
+
+
+static void
+gui_internal_cmd_display(struct gui_priv *this, struct widget *wm)
+{
+	struct widget *w;
+
+	w=gui_internal_menu(this, "Display");	
+	gui_internal_widget_append(w,
+		gui_internal_button_new_with_callback(this, "Layout",
+			image_new_l(this, "gui_display"), gravity_center|orientation_vertical,
+			gui_internal_cmd_layout, NULL));
+	gui_internal_menu_render(this);
+}
+
+
+static void
 gui_internal_cmd_actions(struct gui_priv *this, struct widget *wm)
 {
 	struct widget *w;
@@ -918,6 +1047,100 @@ gui_internal_cmd_actions(struct gui_priv *this, struct widget *wm)
 		gui_internal_button_new_with_callback(this, "172°15'23\" E\n55°23'44\" S",
 			image_new_l(this, "gui_map"), gravity_center|orientation_vertical,
 			gui_internal_cmd_bookmarks, NULL));
+#if 0
+	gui_internal_widget_append(w,
+		gui_internal_button_new_with_callback(this, "172°15'23\" E\n55°23'44\" S",
+			image_new_l(this, "gui_rules"), gravity_center|orientation_vertical,
+			gui_internal_cmd_bookmarks, NULL));
+	gui_internal_widget_append(w,
+		gui_internal_button_new_with_callback(this, "Town",
+			image_new_l(this, "gui_rules"), gravity_center|orientation_vertical,
+			gui_internal_cmd_bookmarks, NULL));
+	gui_internal_widget_append(w,
+		gui_internal_button_new_with_callback(this, "Street",
+			image_new_l(this, "gui_rules"), gravity_center|orientation_vertical,
+			gui_internal_cmd_bookmarks, NULL));
+#endif
+	gui_internal_menu_render(this);
+}
+
+static void
+gui_internal_cmd_maps(struct gui_priv *this, struct widget *wm)
+{
+	struct attr attr;
+	struct widget *w,*wb,*wma;
+	char *label;
+	struct attr_iter *iter;
+	struct attr on, off;
+
+
+	wb=gui_internal_menu(this, "Maps");
+	w=gui_internal_box_new(this, gravity_top_center|orientation_vertical|flags_expand|flags_fill);
+	gui_internal_widget_append(wb, w);
+	iter=navit_attr_iter_new();
+	on.type=off.type=attr_active;
+	on.u.num=1;
+	off.u.num=0;
+	while(navit_get_attr(this->nav, attr_map, &attr, iter)) {
+		label=g_strdup_printf("%s:%s", map_get_type(attr.u.map), map_get_filename(attr.u.map));
+		wma=gui_internal_button_map_attr_new(this, label, gravity_left_center|orientation_horizontal|flags_fill,
+			attr.u.map, &on, &off);
+		gui_internal_widget_append(w, wma);
+		g_free(label);
+	}
+	navit_attr_iter_destroy(iter);
+	gui_internal_menu_render(this);
+	
+}
+
+static void
+gui_internal_cmd_vehicle(struct gui_priv *this, struct widget *wm)
+{
+	struct attr attr,vattr;
+	struct widget *w,*wb,*wl;
+	struct attr_iter *iter;
+
+
+	wb=gui_internal_menu(this, "Vehicle");
+	w=gui_internal_box_new(this, gravity_top_center|orientation_vertical|flags_expand|flags_fill);
+	gui_internal_widget_append(wb, w);
+	iter=navit_attr_iter_new();
+	while(navit_get_attr(this->nav, attr_vehicle, &attr, iter)) {
+		vehicle_get_attr(attr.u.vehicle, attr_name, &vattr);
+		wl=gui_internal_button_navit_attr_new(this, vattr.u.str, gravity_left_center|orientation_horizontal|flags_fill,
+			&attr, NULL);
+		gui_internal_widget_append(w, wl);
+	}
+	navit_attr_iter_destroy(iter);
+	gui_internal_menu_render(this);
+}
+
+
+static void
+gui_internal_cmd_rules(struct gui_priv *this, struct widget *wm)
+{
+	struct widget *wb,*w;
+	struct attr on,off;
+	wb=gui_internal_menu(this, "Rules");	
+	w=gui_internal_box_new(this, gravity_top_center|orientation_vertical|flags_expand|flags_fill);
+	gui_internal_widget_append(wb, w);
+	on.u.num=1;
+	off.u.num=0;
+	on.type=off.type=attr_tracking;
+	gui_internal_widget_append(w,
+		gui_internal_button_navit_attr_new(this, "Stick to roads", gravity_left_center|orientation_horizontal|flags_fill,
+			&on, &off));
+	on.type=off.type=attr_orientation;
+	gui_internal_widget_append(w,
+		gui_internal_button_navit_attr_new(this, "Keep orientation to the North", gravity_left_center|orientation_horizontal|flags_fill,
+			&on, &off));
+	on.type=off.type=attr_cursor;
+	gui_internal_widget_append(w,
+		gui_internal_button_navit_attr_new(this, "Map follows Vehicle", gravity_left_center|orientation_horizontal|flags_fill,
+			&on, &off));
+	gui_internal_widget_append(w,
+		gui_internal_button_new(this, "Attack defenseless civilians",
+			image_new_xs(this, "gui_active"), gravity_left_center|orientation_horizontal|flags_fill));
 	gui_internal_menu_render(this);
 }
 
@@ -928,14 +1151,17 @@ gui_internal_cmd_settings(struct gui_priv *this, struct widget *wm)
 
 	w=gui_internal_menu(this, "Settings");	
 	gui_internal_widget_append(w,
-		gui_internal_button_new(this, "Display",
-			image_new_l(this, "gui_display"), gravity_center|orientation_vertical));
+		gui_internal_button_new_with_callback(this, "Display",
+			image_new_l(this, "gui_display"), gravity_center|orientation_vertical,
+			gui_internal_cmd_display, NULL));
 	gui_internal_widget_append(w,
-		gui_internal_button_new(this, "Maps",
-			image_new_l(this, "gui_maps"), gravity_center|orientation_vertical));
+		gui_internal_button_new_with_callback(this, "Maps",
+			image_new_l(this, "gui_maps"), gravity_center|orientation_vertical,
+			gui_internal_cmd_maps, NULL));
 	gui_internal_widget_append(w,
-		gui_internal_button_new(this, "Sound",
-			image_new_l(this, "gui_sound"), gravity_center|orientation_vertical));
+		gui_internal_button_new_with_callback(this, "Vehicle",
+			image_new_l(this, "gui_sound"), gravity_center|orientation_vertical,
+			gui_internal_cmd_vehicle, NULL));
 	gui_internal_widget_append(w,
 		gui_internal_button_new_with_callback(this, "Rules",
 			image_new_l(this, "gui_rules"), gravity_center|orientation_vertical,
@@ -996,6 +1222,7 @@ static void gui_internal_button(void *data, int pressed, int button, struct poin
 		// check whether the position of the mouse changed during press/release OR if it is the scrollwheel 
 		if (!navit_handle_button(this->nav, pressed, button, p, NULL) || button >=4) // Maybe there's a better way to do this
 			return;
+		navit_block(this->nav, 1);
 		// draw menu
 		this->root.p.x=0;
 		this->root.p.y=0;
@@ -1016,8 +1243,14 @@ static void gui_internal_button(void *data, int pressed, int button, struct poin
 		gui_internal_call_highlighted(this);
 		gui_internal_highlight(this, NULL);
 		graphics_draw_mode(gra, draw_mode_end);
-		if (! this->root.children)
-			navit_draw_displaylist(this->nav);
+		if (! this->root.children) {
+			if (!navit_block(this->nav, 0)) {
+				if (this->redraw)
+					navit_draw(this->nav);
+				else
+					navit_draw_displaylist(this->nav);
+			}
+		}
 	}
 }
 
diff --git a/navit/map.c b/navit/map.c
index 2f0b427b1..c2eb0e7ad 100644
--- a/navit/map.c
+++ b/navit/map.c
@@ -27,6 +27,7 @@
 #include "transform.h"
 #include "item.h"
 #include "plugin.h"
+#include "callback.h"
 #include "country.h"
 
 
@@ -35,6 +36,7 @@ struct map {
 	struct map_priv *priv;
 	char *type;
 	char *filename;
+	struct callback_list *attr_cbl;
 	int active;
 };
 
@@ -65,6 +67,8 @@ map_new(const char *type, struct attr **attrs)
 		g_free(m);
 		m=NULL;
 	}
+	if (m)
+		m->attr_cbl=callback_list_new();
 	return m;
 }
 
@@ -93,6 +97,52 @@ map_set_active(struct map *this_, int active)
 }
 
 int
+map_get_attr(struct map *this_, enum attr_type type, struct attr *attr, struct attr_iter *iter)
+{
+	switch (type) {
+	case attr_active:
+		attr->u.num=this_->active;
+		break;
+	default:
+		return 0;
+	}
+	return 1;
+}
+
+int
+map_set_attr(struct map *this_, struct attr *attr)
+{
+	int attr_updated=0;
+
+	switch (attr->type) {
+	case attr_active:
+		if (this_->active != !!attr->u.num) {
+			this_->active=!!attr->u.num;
+			attr_updated=1;
+		}
+		break;
+	default:
+		return 0;
+	}
+	if (attr_updated)
+		callback_list_call_attr_2(this_->attr_cbl, attr->type, this_, attr);
+}
+
+void
+map_add_callback(struct map *this_, struct callback *cb)
+{
+	callback_list_add(this_->attr_cbl, cb);
+}
+
+void
+map_remove_callback(struct map *this_, struct callback *cb)
+{
+	callback_list_remove(this_->attr_cbl, cb);
+}
+
+
+
+int
 map_requires_conversion(struct map *this_)
 {
 	return (this_->meth.charset != NULL && strcmp(this_->meth.charset, "utf-8"));
diff --git a/navit/map.h b/navit/map.h
index 2b5a539f5..5caa3dd0e 100644
--- a/navit/map.h
+++ b/navit/map.h
@@ -144,10 +144,14 @@ map_selection_contains_polygon(struct map_selection *sel, struct coord *c, int c
 }
 
 /* prototypes */
+enum attr_type;
 enum projection;
 struct attr;
+struct attr_iter;
+struct callback;
 struct item;
 struct map;
+struct map_priv;
 struct map_rect;
 struct map_search;
 struct map_selection;
@@ -156,6 +160,10 @@ char *map_get_filename(struct map *this_);
 char *map_get_type(struct map *this_);
 int map_get_active(struct map *this_);
 void map_set_active(struct map *this_, int active);
+int map_get_attr(struct map *this_, enum attr_type type, struct attr *attr, struct attr_iter *iter);
+int map_set_attr(struct map *this_, struct attr *attr);
+void map_add_callback(struct map *this_, struct callback *cb);
+void map_remove_callback(struct map *this_, struct callback *cb);
 int map_requires_conversion(struct map *this_);
 char *map_convert_string(struct map *this_, char *str);
 void map_convert_free(char *str);
diff --git a/navit/menu.c b/navit/menu.c
index f7a73f6c4..92afa6c73 100644
--- a/navit/menu.c
+++ b/navit/menu.c
@@ -25,8 +25,10 @@ struct menu *
 menu_add(struct menu *menu, char *name, enum menu_type type, struct callback *cb)
 {
 	struct menu *this;
+	if (! menu || ! menu->meth.add)
+		return NULL;
         this=g_new0(struct menu, 1);
-        this->priv=(*menu->meth.add)(menu->priv, &this->meth, name, type, cb);
+	this->priv=(*menu->meth.add)(menu->priv, &this->meth, name, type, cb);
 	if (! this->priv) {
 		g_free(this);
 		return NULL;
diff --git a/navit/navit.c b/navit/navit.c
index 384a08822..399e1a7a5 100644
--- a/navit/navit.c
+++ b/navit/navit.c
@@ -121,6 +121,7 @@ struct navit {
 	struct log *textfile_debug_log;
 	struct pcoord destination;
 	int destination_valid;
+	int blocked;
 };
 
 struct gui *main_loop_gui;
@@ -173,6 +174,10 @@ navit_draw(struct navit *this_)
 	GList *l;
 	struct navit_vehicle *nv;
 
+	if (this_->blocked) {
+		this_->blocked |= 2;
+		return;
+	}
 	transform_setup_source_rect(this_->trans);
 	graphics_draw(this_->gra, this_->displaylist, this_->mapsets, this_->trans, this_->layout_current);
 	l=this_->vehicles;
@@ -1461,6 +1466,8 @@ navit_vehicle_draw(struct navit *this_, struct navit_vehicle *nv, struct point *
 {
 	struct point pnt2;
 	enum projection pro;
+	if (this_->blocked)
+		return;
 	if (pnt)
 		pnt2=*pnt;
 	else {
@@ -1661,6 +1668,22 @@ navit_get_displaylist(struct navit *this_)
 	return this_->displaylist;
 }
 
+int
+navit_block(struct navit *this_, int block)
+{
+	if (block) {
+		this_->blocked |= 1;
+		return;
+	}
+	if (this_->blocked & 2) {
+		this_->blocked=0;
+		navit_draw(this_);
+		return 1;
+	}
+	this_->blocked=0;
+	return 0;
+}
+
 void
 navit_destroy(struct navit *this_)
 {
diff --git a/navit/navit.h b/navit/navit.h
index 2cc39e068..97842fa36 100644
--- a/navit/navit.h
+++ b/navit/navit.h
@@ -89,6 +89,7 @@ struct transformation *navit_get_trans(struct navit *this_);
 struct route *navit_get_route(struct navit *this_);
 struct navigation *navit_get_navigation(struct navit *this_);
 struct displaylist *navit_get_displaylist(struct navit *this_);
+int navit_block(struct navit *this_, int block);
 void navit_destroy(struct navit *this_);
 /* end of prototypes */
 #ifdef __cplusplus