+static void on_poly_enter(GritsPoly *poly)
+{
+ g_debug("on_poly_enter");
+ poly->color[3] = 0.50;
+ grits_object_queue_draw(GRITS_OBJECT(poly));
+}
+
+static void on_poly_leave(GritsPoly *poly)
+{
+ g_debug("on_poly_leave");
+ poly->color[3] = 0.2;
+ grits_object_queue_draw(GRITS_OBJECT(poly));
+}
+
+static void on_poly_button(GritsPoly *poly, GdkEventButton *event)
+{
+ g_debug("on_poly_button");
+ static int i = 0;
+ gdouble colors[][3] = {
+ {1, 0, 0}, {1, 1, 0},
+ {0, 1, 0}, {0, 1, 1},
+ {0, 0, 1}, {1, 0, 1},
+ };
+ int idx = i++ % G_N_ELEMENTS(colors);
+ memcpy(poly->color, colors[idx], sizeof(gdouble)*3);
+ grits_object_queue_draw(GRITS_OBJECT(poly));
+}
+
+static void on_poly_key(GritsPoly *poly, GdkEventKey *event)
+{
+ g_debug("on_poly_key");
+ gdouble colors[0xff][3] = {
+ [GDK_r] {1, 0, 0},
+ [GDK_g] {0, 1, 0},
+ [GDK_b] {0, 0, 1},
+ };
+ int key = event->keyval;
+ memcpy(poly->color, colors[key], sizeof(gdouble)*3);
+ grits_object_queue_draw(GRITS_OBJECT(poly));
+}
+
+static void on_marker_enter(GritsMarker *marker, GritsViewer *viewer)
+{
+ g_debug("on_marker_enter");
+ GdkWindow *window = gtk_widget_get_window(GTK_WIDGET(viewer));
+ GdkCursor *cursor = gdk_cursor_new(GDK_HAND1);
+ gdk_window_set_cursor(window, cursor);
+}
+
+static void on_marker_leave(GritsMarker *marker, GritsViewer *viewer)
+{
+ g_debug("on_marker_leave");
+ GdkWindow *window = gtk_widget_get_window(GTK_WIDGET(viewer));
+ gdk_window_set_cursor(window, NULL);
+}
+
+static void on_marker_button(GritsMarker *marker, GdkEventButton *event)
+{
+ g_debug("on_marker_button");
+ GtkWidget *dialog = gtk_dialog_new_with_buttons(
+ "St. Charles!", NULL, 0, GTK_STOCK_OK, GTK_RESPONSE_OK, NULL);
+ gtk_dialog_run(GTK_DIALOG(dialog));
+}
+