add oscilloscope view

2 files changed, 100 insertions, 0 deletions

diff --git a/gtk/oscilloview.c b/gtk/oscilloview.c
new file mode 100644
index 0000000..724ada9
--- /dev/null
+++ b/gtk/oscilloview.c
@@ -0,0 +1,83 @@
+#include <gtk/gtk.h>
+#include <cairo.h>
+#include "oscilloview.h"
+#include <string.h>
+
+struct oscilloview oscilloview_g = {
+  .flag = ATOMIC_FLAG_INIT
+};
+
+enum {
+  VIEW_SAMPLES = 1024,
+  VIEW_SKIP = 2,
+  WIDTH = 600,
+  HEIGHT = 300,
+};
+
+static struct {
+  GtkWidget *win;
+  struct oscillodata oscillodata[LIBOPNA_OSCILLO_TRACK_COUNT];
+} g;
+
+static void on_destroy(GtkWidget *w, gpointer ptr) {
+  (void)w;
+  (void)ptr;
+  g.win = 0;
+}
+
+static void draw_track(cairo_t *cr,
+                       double x, double y, double w, double h,
+                       const struct oscillodata *data) {
+  int start = OSCILLO_SAMPLE_COUNT - VIEW_SAMPLES;
+  start -= (data->offset >> OSCILLO_OFFSET_SHIFT);
+  if (start < 0) start = 0;
+  for (int i = 0; i < (VIEW_SAMPLES / VIEW_SKIP); i++) {
+    cairo_line_to(cr, x + ((i)*w)/(VIEW_SAMPLES / VIEW_SKIP), y + h/2.0 - (data[0].buf[start + i*VIEW_SKIP] / 16384.0) * h/2);
+  }
+  cairo_stroke(cr);
+}
+
+static gboolean draw_cb(GtkWidget *w,
+                        cairo_t *cr,
+                        gpointer ptr) {
+  (void)w;
+  (void)ptr;
+  cairo_set_antialias(cr, CAIRO_ANTIALIAS_NONE);
+  if (!atomic_flag_test_and_set_explicit(
+    &oscilloview_g.flag, memory_order_acquire)) {
+    memcpy(g.oscillodata,
+           oscilloview_g.oscillodata,
+           sizeof(oscilloview_g.oscillodata));
+    atomic_flag_clear_explicit(&oscilloview_g.flag, memory_order_release);
+  }
+  cairo_set_source_rgb(cr, 0.0, 0.0, 0.0);
+  cairo_paint(cr);
+  cairo_set_source_rgb(cr, 1.0, 1.0, 1.0);
+  for (int x = 0; x < 3; x++) {
+    for (int y = 0; y < 3; y++) {
+      draw_track(cr, x*WIDTH, y*HEIGHT, WIDTH, HEIGHT, &g.oscillodata[x*3+y]);
+    }
+  }
+  return FALSE;
+}
+
+static gboolean tick_cb(GtkWidget *w, GdkFrameClock *clock, gpointer ptr) {
+  (void)clock;
+  (void)ptr;
+  gtk_widget_queue_draw(w);
+  return G_SOURCE_CONTINUE;
+}
+
+void show_oscilloview(void) {
+  if (!g.win) {
+    g.win = gtk_window_new(GTK_WINDOW_TOPLEVEL);
+    gtk_window_set_title(GTK_WINDOW(g.win), "Oscilloscope view");
+    g_signal_connect(g.win, "destroy", G_CALLBACK(on_destroy), 0);
+  }
+  GtkWidget *drawarea = gtk_drawing_area_new();
+  gtk_container_add(GTK_CONTAINER(g.win), drawarea);
+  gtk_widget_set_size_request(drawarea, WIDTH*3, HEIGHT*3);
+  g_signal_connect(drawarea, "draw", G_CALLBACK(draw_cb), 0);
+  gtk_widget_add_tick_callback(drawarea, tick_cb, 0, 0);
+  gtk_widget_show_all(g.win);
+}
diff --git a/gtk/oscilloview.h b/gtk/oscilloview.h
new file mode 100644
index 0000000..edabcd9
--- /dev/null
+++ b/gtk/oscilloview.h
@@ -0,0 +1,17 @@
+#ifndef MYON_FMPLAYER_GTK_OSCILLOVIEW_H_INCLUDED
+#define MYON_FMPLAYER_GTK_OSCILLOVIEW_H_INCLUDED
+
+#include "libopna/opna.h"
+#include "oscillo/oscillo.h"
+
+#include <stdatomic.h>
+
+extern struct oscilloview {
+  atomic_flag flag;
+  struct oscillodata oscillodata[LIBOPNA_OSCILLO_TRACK_COUNT];
+} oscilloview_g;
+
+void show_oscilloview(void);
+
+#endif // MYON_FMPLAYER_GTK_OSCILLOVIEW_H_INCLUDED
+