Add GtkDial:can_control property

If the dial can't be controlled, it shouldn't be dimmed when it's not
sensitive.

src/gtkdial.c

@@ -88,6 +88,7 @@ enum {
   PROP_ROUND_DIGITS,
   PROP_ZERO_DB,
   PROP_TAPER,
+  PROP_CAN_CONTROL,
   LAST_PROP
 };
 
@@ -113,6 +114,7 @@ struct _GtkDial {
   int round_digits;
   double zero_db;
   int taper;
+  gboolean can_control;
 
   // linear taper breakpoints array
   double *taper_breakpoints;
@@ -274,7 +276,7 @@ static void get_dial_properties(
   props->slider_cx = cos(props->angle) * slider_radius + props->cx;
   props->slider_cy = sin(props->angle) * slider_radius + props->cy;
 
-  props->dim = !gtk_widget_is_sensitive(GTK_WIDGET(dial));
+  props->dim = !gtk_widget_is_sensitive(GTK_WIDGET(dial)) && dial->can_control;
 }
 
 static double pdist2(double x1, double y1, double x2, double y2) {
@@ -371,6 +373,20 @@ static void gtk_dial_class_init(GtkDialClass *klass) {
     G_PARAM_READWRITE | G_PARAM_CONSTRUCT
   );
 
+  /**
+   * GtkDial:can-control: (attributes org.gtk.Method.get=gtk_dial_get_can_control org.gtk.Method.set=gtk_dial_set_can_control)
+   *
+   * Whether the dial can be controlled by the user (even though it
+   * might sometimes be insensitive).
+   */
+  properties[PROP_CAN_CONTROL] = g_param_spec_boolean(
+    "can-control",
+    "CanControl",
+    "Whether the dial can be controlled by the user",
+    TRUE,
+    G_PARAM_READWRITE | G_PARAM_CONSTRUCT
+  );
+
   g_object_class_install_properties(g_class, LAST_PROP, properties);
 
   /**
@@ -722,6 +738,9 @@ static void gtk_dial_set_property(
     case PROP_TAPER:
       gtk_dial_set_taper(dial, g_value_get_int(value));
       break;
+    case PROP_CAN_CONTROL:
+      gtk_dial_set_can_control(dial, g_value_get_boolean(value));
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
       break;
@@ -749,6 +768,9 @@ static void gtk_dial_get_property(
     case PROP_TAPER:
       g_value_set_int(value, dial->taper);
       break;
+    case PROP_CAN_CONTROL:
+      g_value_set_boolean(value, dial->can_control);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
       break;
@@ -823,6 +845,14 @@ void gtk_dial_set_taper_linear_breakpoints(
   dial->taper_breakpoints_count = total_count;
 }
 
+void gtk_dial_set_can_control(GtkDial *dial, gboolean can_control) {
+  dial->can_control = can_control;
+}
+
+gboolean gtk_dial_get_can_control(GtkDial *dial) {
+  return dial->can_control;
+}
+
 void gtk_dial_set_adjustment(GtkDial *dial, GtkAdjustment *adj) {
   if (!(adj == NULL || GTK_IS_ADJUSTMENT(adj)))
     return;

src/gtkdial.h

@@ -81,6 +81,9 @@ void gtk_dial_set_taper_linear_breakpoints(
   int           count
 );
 
+void gtk_dial_set_can_control(GtkDial *dial, gboolean can_control);
+gboolean gtk_dial_get_can_control(GtkDial *dial);
+
 G_END_DECLS
 
 #endif

src/iface-mixer.c

@@ -216,7 +216,7 @@ static void create_input_gain_control(
   int               current_row,
   int               column_num
 ) {
-  GtkWidget *w = make_gain_alsa_elem(elem, 0, WIDGET_GAIN_TAPER_LINEAR);
+  GtkWidget *w = make_gain_alsa_elem(elem, 0, WIDGET_GAIN_TAPER_LINEAR, 1);
 
   gtk_grid_attach(GTK_GRID(grid), w, column_num, current_row, 1, 1);
 }
@@ -568,7 +568,7 @@ static void create_output_controls(
     // output controls
     if (strncmp(elem->name, "Line", 4) == 0) {
       if (strstr(elem->name, "Playback Volume")) {
-        w = make_gain_alsa_elem(elem, 1, WIDGET_GAIN_TAPER_LOG);
+        w = make_gain_alsa_elem(elem, 1, WIDGET_GAIN_TAPER_LOG, 1);
         gtk_grid_attach(
           GTK_GRID(output_grid), w, line_num - 1 + line_1_col, 1, 1, 1
         );
@@ -608,9 +608,9 @@ static void create_output_controls(
       GtkWidget *l = gtk_label_new(gen4 ? "Line 1–2" : "HW");
       gtk_grid_attach(GTK_GRID(output_grid), l, 0, 0, 1, 1);
       if (gen4) {
-        w = make_gain_alsa_elem(elem, 1, WIDGET_GAIN_TAPER_GEN4_VOLUME);
+        w = make_gain_alsa_elem(elem, 1, WIDGET_GAIN_TAPER_GEN4_VOLUME, 0);
       } else {
-        w = make_gain_alsa_elem(elem, 1, WIDGET_GAIN_TAPER_LOG);
+        w = make_gain_alsa_elem(elem, 1, WIDGET_GAIN_TAPER_LOG, 0);
       }
       gtk_widget_set_tooltip_text(
         w,
@@ -630,7 +630,7 @@ static void create_output_controls(
         "This control shows the setting of the headphone volume knob."
       );
       gtk_grid_attach(GTK_GRID(output_grid), l, 1, 0, 1, 1);
-      w = make_gain_alsa_elem(elem, 1, WIDGET_GAIN_TAPER_GEN4_VOLUME);
+      w = make_gain_alsa_elem(elem, 1, WIDGET_GAIN_TAPER_GEN4_VOLUME, 0);
       gtk_grid_attach(GTK_GRID(output_grid), w, 1, 1, 1, 1);
     } else if (strcmp(elem->name, "Mute Playback Switch") == 0) {
       w = make_boolean_alsa_elem(

src/widget-gain.c

@@ -60,7 +60,8 @@ static void gain_updated(
 GtkWidget *make_gain_alsa_elem(
   struct alsa_elem *elem,
   int               zero_is_off,
-  int               widget_taper
+  int               widget_taper,
+  int               can_control
 ) {
   struct gain *data = g_malloc(sizeof(struct gain));
   data->elem = elem;
@@ -102,6 +103,8 @@ GtkWidget *make_gain_alsa_elem(
       2
     );
 
+  gtk_dial_set_can_control(GTK_DIAL(data->dial), can_control);
+
   data->label = gtk_label_new(NULL);
   gtk_widget_set_vexpand(data->dial, TRUE);
 

src/widget-gain.h

@@ -16,5 +16,6 @@ enum {
 GtkWidget *make_gain_alsa_elem(
   struct alsa_elem *elem,
   int               zero_is_off,
-  int               taper_type
+  int               taper_type,
+  int               can_control
 );

src/window-levels.c

@@ -103,6 +103,7 @@ GtkWidget *create_levels_controls(struct alsa_card *card) {
       // create the meter widget and attach to the grid
       GtkWidget *meter = gtk_dial_new_with_range(-80, 0, 0, 0);
       gtk_dial_set_taper(GTK_DIAL(meter), GTK_DIAL_TAPER_LINEAR);
+      gtk_dial_set_can_control(GTK_DIAL(meter), FALSE);
       gtk_widget_set_sensitive(meter, FALSE);
       card->meters[meter_num++] = meter;
       gtk_grid_attach(GTK_GRID(grid), meter, j + 1, i + 1, 1, 1);

src/window-mixer.c

@@ -82,7 +82,7 @@ GtkWidget *create_mixer_controls(struct alsa_card *card) {
     }
 
     // create the gain control and attach to the grid
-    GtkWidget *w = make_gain_alsa_elem(elem, 1, WIDGET_GAIN_TAPER_LOG);
+    GtkWidget *w = make_gain_alsa_elem(elem, 1, WIDGET_GAIN_TAPER_LOG, 0);
     gtk_grid_attach(GTK_GRID(mixer_top), w, input_num + 1, mix_num + 2, 1, 1);
 
     // look up the r_snk entry for the mixer input number