diff options
Diffstat (limited to 'demos/gtk-demo/graphwidget.c')
| -rw-r--r-- | demos/gtk-demo/graphwidget.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/demos/gtk-demo/graphwidget.c b/demos/gtk-demo/graphwidget.c new file mode 100644 index 0000000000..9852c7c28f --- /dev/null +++ b/demos/gtk-demo/graphwidget.c @@ -0,0 +1,164 @@ +#include "graphwidget.h" + +struct _GraphWidget +{ + GtkWidget parent_instance; + + GskPath *path; + GskStroke *stroke; + GdkRGBA color; + GskPath *stroke_path; + + guint tick_cb; + guint64 start_time; + + double period; + double amplitude; +}; + +struct _GraphWidgetClass +{ + GtkWidgetClass parent_class; +}; + +G_DEFINE_TYPE (GraphWidget, graph_widget, GTK_TYPE_WIDGET) + +static void +update_path (GraphWidget *self, + float amplitude) +{ + graphene_point_t p[20]; + GskPathBuilder *builder; + + g_clear_pointer (&self->path, gsk_path_unref); + g_clear_pointer (&self->stroke_path, gsk_path_unref); + + for (int i = 0; i < 20; i++) + { + p[i].x = 10 * i; + p[i].y = 50; + + if (i % 4 == 1 || i % 4 == 2) + { + if (i % 8 < 4) + p[i].y += amplitude; + else + p[i].y -= amplitude; + } + } + + builder = gsk_path_builder_new (); + gsk_path_builder_move_to (builder, p[0].x, p[0].y); + + for (int i = 0; i < 20; i += 4) + gsk_path_builder_curve_to (builder, + p[i+1].x, p[i+1].y, + p[i+2].x, p[i+2].y, + p[i+3].x, p[i+3].y); + + self->path = gsk_path_builder_free_to_path (builder); + self->stroke_path = gsk_path_stroke (self->path, self->stroke); +} + +static gboolean +tick_cb (GtkWidget *widget, + GdkFrameClock *frame_clock, + gpointer user_data) +{ + GraphWidget *self = GRAPH_WIDGET (widget); + guint64 now; + double angle; + + now = gdk_frame_clock_get_frame_time (frame_clock); + + if (self->start_time == 0) + self->start_time = now; + + angle = 360 * (now - self->start_time) / (double)(self->period * G_TIME_SPAN_MINUTE); + update_path (self, sin (angle) * self->amplitude); + + gtk_widget_queue_draw (widget); + + return G_SOURCE_CONTINUE; +} + +static void +graph_widget_init (GraphWidget *self) +{ + self->color.red = g_random_double_range (0, 1); + self->color.green = g_random_double_range (0, 1); + self->color.blue = g_random_double_range (0, 1); + self->color.alpha = 1; + + self->period = g_random_double_range (0.5, 1); + self->amplitude = g_random_double_range (10, 25); + + self->stroke = gsk_stroke_new (2); + + update_path (self, 0); + + self->start_time = 0; + self->tick_cb = gtk_widget_add_tick_callback (GTK_WIDGET (self), tick_cb, NULL, NULL); +} + +static void +graph_widget_dispose (GObject *object) +{ + GraphWidget *self = GRAPH_WIDGET (object); + + gsk_path_unref (self->path); + gsk_stroke_free (self->stroke); + + G_OBJECT_CLASS (graph_widget_parent_class)->dispose (object); +} + +static void +graph_widget_snapshot (GtkWidget *widget, + GtkSnapshot *snapshot) +{ + GraphWidget *self = GRAPH_WIDGET (widget); + int width, height; + + width = gtk_widget_get_width (widget); + height = gtk_widget_get_height (widget); + + gtk_snapshot_push_fill (snapshot, self->stroke_path, GSK_FILL_RULE_WINDING); + gtk_snapshot_append_color (snapshot, + &self->color, + &GRAPHENE_RECT_INIT (0, 0, width, height)); + gtk_snapshot_pop (snapshot); +} + +static void +graph_widget_measure (GtkWidget *widget, + GtkOrientation orientation, + int for_size, + int *minimum, + int *natural, + int *minimum_baseline, + int *natural_baseline) +{ + if (orientation == GTK_ORIENTATION_HORIZONTAL) + *minimum = *natural = 200; + else + *minimum = *natural = 100; +} + + +static void +graph_widget_class_init (GraphWidgetClass *class) +{ + GObjectClass *object_class = G_OBJECT_CLASS (class); + GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class); + + object_class->dispose = graph_widget_dispose; + + widget_class->snapshot = graph_widget_snapshot; + widget_class->measure = graph_widget_measure; +} + +GtkWidget * +graph_widget_new (void) +{ + return g_object_new (GRAPH_TYPE_WIDGET, NULL); +} |