From a69285da08a2a61d5fd817ee8ccb88a6b6deaef6 Mon Sep 17 00:00:00 2001 From: "Owen W. Taylor" Date: Wed, 26 Sep 2012 10:28:06 -0400 Subject: [PATCH] Compress motion synchronized with the paint cycle When we have pending motion events, instead of delivering them directly, request the new FLUSH_EVENTS phase of the frame clock. This allows us to compress repeated motion events sent to the same window. In the FLUSH_EVENTS phase, which occur at priority GDK_PRIORITY_EVENTS + 1, we deliver any pending motion events then turn off event delivery until the end of the next frame. Turning off event delivery means that we'll reliably paint the compressed motion events even if more have arrived. Add a motion-compression test case which demonstrates behavior when an application takes too long handle motion events. It is unusable without this patch but behaves fine with the patch. https://bugzilla.gnome.org/show_bug.cgi?id=685460 --- gdk/gdkdisplay.c | 31 +++++++++- gdk/gdkdisplayprivate.h | 5 ++ gdk/gdkevents.c | 69 ++++++++++++++++++++- gdk/gdkframeclock.c | 32 ++++++++++ gdk/gdkframeclock.h | 16 +++-- gdk/gdkframeclockidle.c | 121 ++++++++++++++++++++++++++++++------- gdk/gdkinternals.h | 3 + gdk/gdkwindow.c | 59 ++++++++++++++++-- tests/Makefile.am | 2 + tests/motion-compression.c | 72 ++++++++++++++++++++++ 10 files changed, 373 insertions(+), 37 deletions(-) create mode 100644 tests/motion-compression.c diff --git a/gdk/gdkdisplay.c b/gdk/gdkdisplay.c index b02ab8a54..8e5092c4d 100644 --- a/gdk/gdkdisplay.c +++ b/gdk/gdkdisplay.c @@ -308,7 +308,11 @@ gdk_display_get_event (GdkDisplay *display) g_return_val_if_fail (GDK_IS_DISPLAY (display), NULL); GDK_DISPLAY_GET_CLASS (display)->queue_events (display); - return _gdk_event_unqueue (display); + + if (display->events_paused) + return NULL; + else + return _gdk_event_unqueue (display); } /** @@ -2003,6 +2007,31 @@ gdk_display_notify_startup_complete (GdkDisplay *display, GDK_DISPLAY_GET_CLASS (display)->notify_startup_complete (display, startup_id); } +void +_gdk_display_set_events_paused (GdkDisplay *display, + gboolean events_paused) +{ + display->events_paused = !!events_paused; +} + +void +_gdk_display_flush_events (GdkDisplay *display) +{ + display->flushing_events = TRUE; + + while (TRUE) + { + GdkEvent *event = _gdk_event_unqueue (display); + if (event == NULL) + break; + + _gdk_event_emit (event); + gdk_event_free (event); + } + + display->flushing_events = FALSE; +} + void _gdk_display_event_data_copy (GdkDisplay *display, const GdkEvent *event, diff --git a/gdk/gdkdisplayprivate.h b/gdk/gdkdisplayprivate.h index 6549f213a..8f448eba7 100644 --- a/gdk/gdkdisplayprivate.h +++ b/gdk/gdkdisplayprivate.h @@ -114,6 +114,8 @@ struct _GdkDisplay GdkDevice *core_pointer; /* Core pointer device */ guint closed : 1; /* Whether this display has been closed */ + guint events_paused : 1; /* Whether events are blocked */ + guint flushing_events : 1; /* Inside gdk_display_flush_events */ GArray *touch_implicit_grabs; GHashTable *device_grabs; @@ -296,6 +298,9 @@ void _gdk_display_pointer_info_foreach (GdkDisplay *display GdkDisplayPointerInfoForeach func, gpointer user_data); gulong _gdk_display_get_next_serial (GdkDisplay *display); +void _gdk_display_set_events_paused (GdkDisplay *display, + gboolean events_paused); +void _gdk_display_flush_events (GdkDisplay *display); void _gdk_display_event_data_copy (GdkDisplay *display, const GdkEvent *event, GdkEvent *new_event); diff --git a/gdk/gdkevents.c b/gdk/gdkevents.c index 204863c4b..d068e13c2 100644 --- a/gdk/gdkevents.c +++ b/gdk/gdkevents.c @@ -85,13 +85,27 @@ _gdk_event_emit (GdkEvent *event) GList* _gdk_event_queue_find_first (GdkDisplay *display) { - GList *tmp_list = display->queued_events; + GList *tmp_list; + GList *pending_motion = NULL; + + if (display->events_paused) + return NULL; + tmp_list = display->queued_events; while (tmp_list) { GdkEventPrivate *event = tmp_list->data; - if (!(event->flags & GDK_EVENT_PENDING)) - return tmp_list; + + if (event->flags & GDK_EVENT_PENDING) + continue; + + if (pending_motion) + return pending_motion; + + if (event->event.type == GDK_MOTION_NOTIFY && !display->flushing_events) + pending_motion = tmp_list; + else + return tmp_list; tmp_list = g_list_next (tmp_list); } @@ -248,6 +262,55 @@ _gdk_event_unqueue (GdkDisplay *display) return event; } +void +_gdk_event_queue_handle_motion_compression (GdkDisplay *display) +{ + GList *tmp_list; + GList *pending_motions = NULL; + GdkWindow *pending_motion_window = NULL; + + /* If the last N events in the event queue are motion notify + * events for the same window, drop all but the last */ + + tmp_list = display->queued_tail; + + while (tmp_list) + { + GdkEventPrivate *event = tmp_list->data; + + if (event->flags & GDK_EVENT_PENDING) + break; + + if (event->event.type != GDK_MOTION_NOTIFY) + break; + + if (pending_motion_window != NULL && + pending_motion_window != event->event.motion.window) + break; + + pending_motion_window = event->event.motion.window; + pending_motions = tmp_list; + + tmp_list = tmp_list->prev; + } + + while (pending_motions && pending_motions->next != NULL) + { + GList *next = pending_motions->next; + display->queued_events = g_list_delete_link (display->queued_events, + pending_motions); + pending_motions = next; + } + + if (pending_motions && + pending_motions == display->queued_events && + pending_motions == display->queued_tail) + { + GdkFrameClock *clock = gdk_window_get_frame_clock (pending_motion_window); + gdk_frame_clock_request_phase (clock, GDK_FRAME_CLOCK_PHASE_FLUSH_EVENTS); + } +} + /** * gdk_event_handler_set: * @func: the function to call to handle events from GDK. diff --git a/gdk/gdkframeclock.c b/gdk/gdkframeclock.c index 569ab6b52..8c6d20210 100644 --- a/gdk/gdkframeclock.c +++ b/gdk/gdkframeclock.c @@ -91,11 +91,13 @@ G_DEFINE_INTERFACE (GdkFrameClock, gdk_frame_clock, G_TYPE_OBJECT) enum { FRAME_REQUESTED, + FLUSH_EVENTS, BEFORE_PAINT, UPDATE, LAYOUT, PAINT, AFTER_PAINT, + RESUME_EVENTS, LAST_SIGNAL }; @@ -120,6 +122,21 @@ gdk_frame_clock_default_init (GdkFrameClockInterface *iface) g_cclosure_marshal_VOID__VOID, G_TYPE_NONE, 0); + /** + * GdkFrameClock::flush-events: + * @clock: the frame clock emitting the signal + * + * FIXME. + */ + signals[FLUSH_EVENTS] = + g_signal_new (g_intern_static_string ("flush-events"), + GDK_TYPE_FRAME_CLOCK, + G_SIGNAL_RUN_LAST, + 0, + NULL, NULL, + g_cclosure_marshal_VOID__VOID, + G_TYPE_NONE, 0); + /** * GdkFrameClock::before-paint: * @clock: the frame clock emitting the signal @@ -202,6 +219,21 @@ gdk_frame_clock_default_init (GdkFrameClockInterface *iface) NULL, NULL, g_cclosure_marshal_VOID__VOID, G_TYPE_NONE, 0); + + /** + * GdkFrameClock::resume-events: + * @clock: the frame clock emitting the signal + * + * FIXME. + */ + signals[RESUME_EVENTS] = + g_signal_new (g_intern_static_string ("resume-events"), + GDK_TYPE_FRAME_CLOCK, + G_SIGNAL_RUN_LAST, + 0, + NULL, NULL, + g_cclosure_marshal_VOID__VOID, + G_TYPE_NONE, 0); } /** diff --git a/gdk/gdkframeclock.h b/gdk/gdkframeclock.h index ae445737d..624f6fef4 100644 --- a/gdk/gdkframeclock.h +++ b/gdk/gdkframeclock.h @@ -64,12 +64,14 @@ void gdk_frame_clock_target_set_clock (GdkFrameClockTarget *target, #define GDK_FRAME_CLOCK_GET_IFACE(inst) (G_TYPE_INSTANCE_GET_INTERFACE ((inst), GDK_TYPE_FRAME_CLOCK, GdkFrameClockInterface)) typedef enum { - GDK_FRAME_CLOCK_PHASE_NONE = 0, - GDK_FRAME_CLOCK_PHASE_BEFORE_PAINT = 1 << 0, - GDK_FRAME_CLOCK_PHASE_UPDATE = 1 << 1, - GDK_FRAME_CLOCK_PHASE_LAYOUT = 1 << 2, - GDK_FRAME_CLOCK_PHASE_PAINT = 1 << 3, - GDK_FRAME_CLOCK_PHASE_AFTER_PAINT = 1 << 4 + GDK_FRAME_CLOCK_PHASE_NONE = 0, + GDK_FRAME_CLOCK_PHASE_FLUSH_EVENTS = 1 << 0, + GDK_FRAME_CLOCK_PHASE_BEFORE_PAINT = 1 << 1, + GDK_FRAME_CLOCK_PHASE_UPDATE = 1 << 2, + GDK_FRAME_CLOCK_PHASE_LAYOUT = 1 << 3, + GDK_FRAME_CLOCK_PHASE_PAINT = 1 << 4, + GDK_FRAME_CLOCK_PHASE_AFTER_PAINT = 1 << 5, + GDK_FRAME_CLOCK_PHASE_RESUME_EVENTS = 1 << 6 } GdkFrameClockPhase; struct _GdkFrameClockInterface @@ -87,11 +89,13 @@ struct _GdkFrameClockInterface /* signals */ /* void (* frame_requested) (GdkFrameClock *clock); */ + /* void (* flush_events) (GdkFrameClock *clock); */ /* void (* before_paint) (GdkFrameClock *clock); */ /* void (* update) (GdkFrameClock *clock); */ /* void (* layout) (GdkFrameClock *clock); */ /* void (* paint) (GdkFrameClock *clock); */ /* void (* after_paint) (GdkFrameClock *clock); */ + /* void (* resume_events) (GdkFrameClock *clock); */ }; GType gdk_frame_clock_get_type (void) G_GNUC_CONST; diff --git a/gdk/gdkframeclockidle.c b/gdk/gdkframeclockidle.c index bf68fd1b6..ff4b479ae 100644 --- a/gdk/gdkframeclockidle.c +++ b/gdk/gdkframeclockidle.c @@ -39,13 +39,15 @@ struct _GdkFrameClockIdlePrivate guint64 frame_time; guint64 min_next_frame_time; - guint idle_id; + guint flush_idle_id; + guint paint_idle_id; guint freeze_count; GdkFrameClockPhase requested; GdkFrameClockPhase phase; }; +static gboolean gdk_frame_clock_flush_idle (void *data); static gboolean gdk_frame_clock_paint_idle (void *data); static void gdk_frame_clock_idle_finalize (GObject *object); @@ -144,7 +146,7 @@ maybe_start_idle (GdkFrameClockIdle *clock_idle) { GdkFrameClockIdlePrivate *priv = clock_idle->priv; - if (priv->idle_id == 0 && priv->freeze_count == 0 && priv->requested != 0) + if (priv->freeze_count == 0) { guint min_interval = 0; @@ -155,41 +157,89 @@ maybe_start_idle (GdkFrameClockIdle *clock_idle) min_interval = (min_interval_us + 500) / 1000; } - priv->idle_id = gdk_threads_add_timeout_full (GDK_PRIORITY_REDRAW, - min_interval, - gdk_frame_clock_paint_idle, - g_object_ref (clock_idle), - (GDestroyNotify) g_object_unref); + if (priv->flush_idle_id == 0 && + (priv->requested & GDK_FRAME_CLOCK_PHASE_FLUSH_EVENTS) != 0) + { + priv->flush_idle_id = gdk_threads_add_timeout_full (GDK_PRIORITY_EVENTS + 1, + min_interval, + gdk_frame_clock_flush_idle, + g_object_ref (clock_idle), + (GDestroyNotify) g_object_unref); + } + + if (priv->paint_idle_id == 0 && + (priv->requested & ~GDK_FRAME_CLOCK_PHASE_FLUSH_EVENTS) != 0) + { + priv->paint_idle_id = gdk_threads_add_timeout_full (GDK_PRIORITY_REDRAW, + min_interval, + gdk_frame_clock_paint_idle, + g_object_ref (clock_idle), + (GDestroyNotify) g_object_unref); - gdk_frame_clock_frame_requested (GDK_FRAME_CLOCK (clock_idle)); + gdk_frame_clock_frame_requested (GDK_FRAME_CLOCK (clock_idle)); + } } } +static gboolean +gdk_frame_clock_flush_idle (void *data) +{ + GdkFrameClock *clock = GDK_FRAME_CLOCK (data); + GdkFrameClockIdle *clock_idle = GDK_FRAME_CLOCK_IDLE (clock); + GdkFrameClockIdlePrivate *priv = clock_idle->priv; + + priv->flush_idle_id = 0; + + if (priv->phase != GDK_FRAME_CLOCK_PHASE_NONE) + return FALSE; + + priv->phase = GDK_FRAME_CLOCK_PHASE_FLUSH_EVENTS; + priv->requested &= ~GDK_FRAME_CLOCK_PHASE_FLUSH_EVENTS; + + g_signal_emit_by_name (G_OBJECT (clock), "flush-events"); + + if ((priv->requested & ~GDK_FRAME_CLOCK_PHASE_FLUSH_EVENTS) != 0) + priv->phase = GDK_FRAME_CLOCK_PHASE_BEFORE_PAINT; + else + priv->phase = GDK_FRAME_CLOCK_PHASE_NONE; + + return FALSE; +} + static gboolean gdk_frame_clock_paint_idle (void *data) { GdkFrameClock *clock = GDK_FRAME_CLOCK (data); GdkFrameClockIdle *clock_idle = GDK_FRAME_CLOCK_IDLE (clock); GdkFrameClockIdlePrivate *priv = clock_idle->priv; + gboolean skip_to_resume_events; - priv->idle_id = 0; + priv->paint_idle_id = 0; + + skip_to_resume_events = + (priv->requested & ~(GDK_FRAME_CLOCK_PHASE_FLUSH_EVENTS | GDK_FRAME_CLOCK_PHASE_RESUME_EVENTS)) == 0; switch (priv->phase) { + case GDK_FRAME_CLOCK_PHASE_FLUSH_EVENTS: + break; case GDK_FRAME_CLOCK_PHASE_NONE: case GDK_FRAME_CLOCK_PHASE_BEFORE_PAINT: if (priv->freeze_count == 0) { priv->frame_time = compute_frame_time (clock_idle); - priv->phase = GDK_FRAME_CLOCK_PHASE_BEFORE_PAINT; - priv->requested &= ~GDK_FRAME_CLOCK_PHASE_BEFORE_PAINT; - /* We always emit ::before-paint and ::after-paint even if - * not explicitly requested, and unlike other phases, + priv->phase = GDK_FRAME_CLOCK_PHASE_BEFORE_PAINT; + /* We always emit ::before-paint and ::after-paint if + * any of the intermediate phases are requested and * they don't get repeated if you freeze/thaw while * in them. */ - g_signal_emit_by_name (G_OBJECT (clock), "before-paint"); - priv->phase = GDK_FRAME_CLOCK_PHASE_UPDATE; + if (!skip_to_resume_events) + { + priv->requested &= ~GDK_FRAME_CLOCK_PHASE_BEFORE_PAINT; + g_signal_emit_by_name (G_OBJECT (clock), "before-paint"); + } + priv->phase = GDK_FRAME_CLOCK_PHASE_UPDATE; } case GDK_FRAME_CLOCK_PHASE_UPDATE: if (priv->freeze_count == 0) @@ -224,9 +274,24 @@ gdk_frame_clock_paint_idle (void *data) if (priv->freeze_count == 0) { priv->phase = GDK_FRAME_CLOCK_PHASE_AFTER_PAINT; - priv->requested &= ~GDK_FRAME_CLOCK_PHASE_AFTER_PAINT; - g_signal_emit_by_name (G_OBJECT (clock), "after-paint"); - /* the ::after-paint phase doesn't get repeated on freeze/thaw */ + if (!skip_to_resume_events) + { + priv->requested &= ~GDK_FRAME_CLOCK_PHASE_AFTER_PAINT; + g_signal_emit_by_name (G_OBJECT (clock), "after-paint"); + } + /* the ::after-paint phase doesn't get repeated on freeze/thaw, + */ + priv->phase = GDK_FRAME_CLOCK_PHASE_RESUME_EVENTS; + } + case GDK_FRAME_CLOCK_PHASE_RESUME_EVENTS: + if (priv->freeze_count == 0) + { + if (priv->requested & GDK_FRAME_CLOCK_PHASE_RESUME_EVENTS) + { + priv->requested &= ~GDK_FRAME_CLOCK_PHASE_RESUME_EVENTS; + g_signal_emit_by_name (G_OBJECT (clock), "resume-events"); + } + /* the ::resume-event phase doesn't get repeated on freeze/thaw */ priv->phase = GDK_FRAME_CLOCK_PHASE_NONE; } } @@ -276,10 +341,15 @@ gdk_frame_clock_idle_freeze (GdkFrameClock *clock) if (priv->freeze_count == 1) { - if (priv->idle_id) + if (priv->flush_idle_id) { - g_source_remove (priv->idle_id); - priv->idle_id = 0; + g_source_remove (priv->flush_idle_id); + priv->flush_idle_id = 0; + } + if (priv->paint_idle_id) + { + g_source_remove (priv->paint_idle_id); + priv->paint_idle_id = 0; } } } @@ -294,7 +364,14 @@ gdk_frame_clock_idle_thaw (GdkFrameClock *clock) priv->freeze_count--; if (priv->freeze_count == 0) - maybe_start_idle (clock_idle); + { + maybe_start_idle (clock_idle); + /* If nothing is requested so we didn't start an idle, we need + * to skip to the end of the state chain, since the idle won't + * run and do it for us. */ + if (priv->paint_idle_id == 0) + priv->phase = GDK_FRAME_CLOCK_PHASE_NONE; + } } static void diff --git a/gdk/gdkinternals.h b/gdk/gdkinternals.h index fb561e6f7..babef6e7f 100644 --- a/gdk/gdkinternals.h +++ b/gdk/gdkinternals.h @@ -300,6 +300,9 @@ GList* _gdk_event_queue_insert_after (GdkDisplay *display, GList* _gdk_event_queue_insert_before(GdkDisplay *display, GdkEvent *after_event, GdkEvent *event); + +void _gdk_event_queue_handle_motion_compression (GdkDisplay *display); + void _gdk_event_button_generate (GdkDisplay *display, GdkEvent *event); diff --git a/gdk/gdkwindow.c b/gdk/gdkwindow.c index 0505d3fb6..0ac0cfeda 100644 --- a/gdk/gdkwindow.c +++ b/gdk/gdkwindow.c @@ -10038,7 +10038,7 @@ _gdk_windowing_got_event (GdkDisplay *display, { GdkWindow *event_window; gdouble x, y; - gboolean unlink_event; + gboolean unlink_event = FALSE; GdkDeviceGrabInfo *button_release_grab; GdkPointerWindowInfo *pointer_info = NULL; GdkDevice *device, *source_device; @@ -10081,7 +10081,7 @@ _gdk_windowing_got_event (GdkDisplay *display, event_window = event->any.window; if (!event_window) - return; + goto out; #ifdef DEBUG_WINDOW_PRINTING if (event->type == GDK_KEY_PRESS && @@ -10096,13 +10096,13 @@ _gdk_windowing_got_event (GdkDisplay *display, { event_window->native_visibility = event->visibility.state; gdk_window_update_visibility_recursively (event_window, event_window); - return; + goto out; } if (!(is_button_type (event->type) || is_motion_type (event->type)) || event_window->window_type == GDK_WINDOW_ROOT) - return; + goto out; is_toplevel = gdk_window_is_toplevel (event_window); @@ -10195,7 +10195,6 @@ _gdk_windowing_got_event (GdkDisplay *display, _gdk_display_enable_motion_hints (display, device); } - unlink_event = FALSE; if (is_motion_type (event->type)) unlink_event = proxy_pointer_event (display, event, serial); else if (is_button_type (event->type)) @@ -10237,6 +10236,13 @@ _gdk_windowing_got_event (GdkDisplay *display, g_list_free_1 (event_link); gdk_event_free (event); } + + /* This does two things - first it sees if there are motions at the + * end of the queue that can be compressed. Second, if there is just + * a single motion that won't be dispatched because it is a compression + * candidate it queues up flushing the event queue. + */ + _gdk_event_queue_handle_motion_compression (display); } /** @@ -11603,6 +11609,22 @@ gdk_property_delete (GdkWindow *window, GDK_WINDOW_IMPL_GET_CLASS (window->impl)->delete_property (window, property); } +static void +gdk_window_flush_events (GdkFrameClock *clock, + void *data) +{ + GdkWindow *window; + GdkDisplay *display; + + window = GDK_WINDOW (data); + + display = gdk_window_get_display (window); + _gdk_display_flush_events (display); + _gdk_display_set_events_paused (display, TRUE); + + gdk_frame_clock_request_phase (clock, GDK_FRAME_CLOCK_PHASE_RESUME_EVENTS); +} + static void gdk_window_paint_on_clock (GdkFrameClock *clock, void *data) @@ -11616,6 +11638,19 @@ gdk_window_paint_on_clock (GdkFrameClock *clock, gdk_window_process_updates_with_mode (window, PROCESS_UPDATES_WITH_SAME_CLOCK_CHILDREN); } +static void +gdk_window_resume_events (GdkFrameClock *clock, + void *data) +{ + GdkWindow *window; + GdkDisplay *display; + + window = GDK_WINDOW (data); + + display = gdk_window_get_display (window); + _gdk_display_set_events_paused (display, FALSE); +} + /** * gdk_window_set_frame_clock: * @window: window to set frame clock on @@ -11651,17 +11686,31 @@ gdk_window_set_frame_clock (GdkWindow *window, if (clock) { g_object_ref (clock); + g_signal_connect (G_OBJECT (clock), + "flush-events", + G_CALLBACK (gdk_window_flush_events), + window); g_signal_connect (G_OBJECT (clock), "paint", G_CALLBACK (gdk_window_paint_on_clock), window); + g_signal_connect (G_OBJECT (clock), + "resume-events", + G_CALLBACK (gdk_window_resume_events), + window); } if (window->frame_clock) { + g_signal_handlers_disconnect_by_func (G_OBJECT (window->frame_clock), + G_CALLBACK (gdk_window_flush_events), + window); g_signal_handlers_disconnect_by_func (G_OBJECT (window->frame_clock), G_CALLBACK (gdk_window_paint_on_clock), window); + g_signal_handlers_disconnect_by_func (G_OBJECT (window->frame_clock), + G_CALLBACK (gdk_window_resume_events), + window); g_object_unref (window->frame_clock); } diff --git a/tests/Makefile.am b/tests/Makefile.am index 791790509..59f1678fc 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -26,6 +26,7 @@ endif noinst_PROGRAMS = $(TEST_PROGS) \ animated-resizing \ + motion-compression \ simple \ flicker \ print-editor \ @@ -152,6 +153,7 @@ endif animated_resizing_DEPENDENCIES = $(TEST_DEPS) flicker_DEPENDENCIES = $(TEST_DEPS) +motion_compression_DEPENDENCIES = $(TEST_DEPS) simple_DEPENDENCIES = $(TEST_DEPS) print_editor_DEPENDENCIES = $(TEST_DEPS) testheightforwidth_DEPENDENCIES = $(TEST_DEPS) diff --git a/tests/motion-compression.c b/tests/motion-compression.c new file mode 100644 index 000000000..c7effad9a --- /dev/null +++ b/tests/motion-compression.c @@ -0,0 +1,72 @@ +#include +#include + +GtkAdjustment *adjustment; +int cursor_x, cursor_y; + +static void +on_motion_notify (GtkWidget *window, + GdkEventMotion *event) +{ + if (event->window == gtk_widget_get_window (window)) + { + float processing_ms = gtk_adjustment_get_value (adjustment); + g_usleep (processing_ms * 1000); + cursor_x = event->x; + cursor_y = event->y; + gtk_widget_queue_draw (window); + } +} + +static void +on_draw (GtkWidget *window, + cairo_t *cr) +{ + cairo_set_source_rgb (cr, 1, 1, 1); + cairo_paint (cr); + + cairo_set_source_rgb (cr, 0, 0.5, 0.5); + + cairo_arc (cr, cursor_x, cursor_y, 10, 0, 2 * M_PI); + cairo_stroke (cr); +} + +int +main (int argc, char **argv) +{ + GtkWidget *window; + GtkWidget *vbox; + GtkWidget *label; + GtkWidget *scale; + + gtk_init (&argc, &argv); + + window = gtk_window_new (GTK_WINDOW_TOPLEVEL); + gtk_window_set_default_size (GTK_WINDOW (window), 300, 300); + gtk_widget_set_app_paintable (window, TRUE); + gtk_widget_add_events (window, GDK_POINTER_MOTION_MASK); + gtk_widget_set_app_paintable (window, TRUE); + + vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 0); + gtk_container_add (GTK_CONTAINER (window), vbox); + + adjustment = gtk_adjustment_new (20, 0, 200, 1, 10, 0); + scale = gtk_scale_new (GTK_ORIENTATION_HORIZONTAL, adjustment); + gtk_box_pack_end (GTK_BOX (vbox), scale, FALSE, FALSE, 0); + + label = gtk_label_new ("Event processing time (ms):"); + gtk_misc_set_alignment (GTK_MISC (label), 0.0, 0.5); + gtk_box_pack_end (GTK_BOX (vbox), label, FALSE, FALSE, 0); + + g_signal_connect (window, "motion-notify-event", + G_CALLBACK (on_motion_notify), NULL); + g_signal_connect (window, "draw", + G_CALLBACK (on_draw), NULL); + g_signal_connect (window, "destroy", + G_CALLBACK (gtk_main_quit), NULL); + + gtk_widget_show_all (window); + gtk_main (); + + return 0; +} -- 2.43.2