Learning_GTK4_tree/tests/motion-compression.c

94 lines
2.2 KiB
C

#include <gtk/gtk.h>
#include <math.h>
GtkAdjustment *adjustment;
int cursor_x, cursor_y;
static void
motion_cb (GtkEventControllerMotion *motion,
double x,
double y,
GtkWidget *widget)
{
float processing_ms = gtk_adjustment_get_value (adjustment);
g_usleep (processing_ms * 1000);
cursor_x = x;
cursor_y = y;
gtk_widget_queue_draw (widget);
}
static void
on_draw (GtkDrawingArea *da,
cairo_t *cr,
int width,
int height,
gpointer data)
{
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);
}
static void
quit_cb (GtkWidget *widget,
gpointer data)
{
gboolean *done = data;
*done = TRUE;
g_main_context_wakeup (NULL);
}
int
main (int argc, char **argv)
{
GtkWidget *window;
GtkWidget *vbox;
GtkWidget *label;
GtkWidget *scale;
GtkWidget *da;
GtkEventController *controller;
gboolean done = FALSE;
gtk_init ();
window = gtk_window_new ();
gtk_window_set_default_size (GTK_WINDOW (window), 300, 300);
vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 0);
gtk_window_set_child (GTK_WINDOW (window), vbox);
da = gtk_drawing_area_new ();
gtk_drawing_area_set_draw_func (GTK_DRAWING_AREA (da), on_draw, NULL, NULL);
gtk_widget_set_vexpand (da, TRUE);
gtk_box_append (GTK_BOX (vbox), da);
label = gtk_label_new ("Event processing time (ms):");
gtk_widget_set_halign (label, GTK_ALIGN_CENTER);
gtk_box_append (GTK_BOX (vbox), label);
adjustment = gtk_adjustment_new (20, 0, 200, 1, 10, 0);
scale = gtk_scale_new (GTK_ORIENTATION_HORIZONTAL, adjustment);
gtk_box_append (GTK_BOX (vbox), scale);
controller = gtk_event_controller_motion_new ();
g_signal_connect (controller, "motion",
G_CALLBACK (motion_cb), da);
gtk_widget_add_controller (da, controller);
g_signal_connect (window, "destroy",
G_CALLBACK (quit_cb), &done);
gtk_window_present (GTK_WINDOW (window));
while (!done)
g_main_context_iteration (NULL, TRUE);
return 0;
}