Extract window opacity logic

2 files changed, 30 insertions, 24 deletions

diff --git a/x11.c b/x11.c
index df072b9..b8e105b 100644
--- a/x11.c
+++ b/x11.c
@@ -93,6 +93,8 @@ static gboolean xcb_source_dispatch(GSource *source, GSourceFunc callback, gpoin
 
             case XCB_PROPERTY_NOTIFY: {
                 xcb_property_notify_event_t *property = (xcb_property_notify_event_t *)xsource->event;
+                log_debug("Processing event 'PropertyNotify' [type %d]", XCB_PROPERTY_NOTIFY);
+
                 if (property->atom == XCB_ATOM_RESOURCE_MANAGER) {
                     window_update_scale(data);
 
@@ -257,26 +259,6 @@ found_visual:
     xcb_icccm_set_wm_name(win->connection, win->window, XCB_ATOM_STRING, 8, strlen("comet"), "comet");
     xcb_map_window(win->connection, win->window);
 
-    //xcb_atom_t NET_WM_WINDOW_OPACITY = intern_atom(win, "_NET_WM_WINDOW_OPACITY");
-    //xcb_atom_t CARDINAL = intern_atom(win, "CARDINAL");
-
-    // Value between 0 and 1
-    //double transparency = 0.8;
-    //unsigned long opacity = 0xffffffff * transparency;
-
-    //error =
-    //xcb_request_check(win->connection,
-    //xcb_change_property_checked(win->connection,
-    //                    XCB_PROP_MODE_REPLACE,
-    //                    win->window,
-    //                    NET_WM_WINDOW_OPACITY,
-    //                    CARDINAL,
-    //                    32,
-    //                    1,
-    //                    (char *)&opacity));
-    //assert(error == NULL);
-    //log_debug("Window '%s' set to '%d%%'", "opacity", (int)round(100 - 100 * transparency));
-
     xcb_flush(win->connection);
     log_debug("Xcb initialized");
 
@@ -306,16 +288,18 @@ cairo_t *window_get_context(Window *win)
 
 void window_update_scale(Window *win)
 {
+    const char *dpi_res = "Xft.dpi";
     char *dpi_value;
-    if (xcb_xrm_resource_get_string(win->database, "Xft.dpi", "Xft.dpi", &dpi_value) >= 0) {
-        log_debug("Xrm query '%s' found '%s'", "Xft.dpi", dpi_value);
+
+    if (xcb_xrm_resource_get_string(win->database, dpi_res, dpi_res, &dpi_value) >= 0) {
+        log_debug("Xrm query '%s' found '%s'", dpi_res, dpi_value);
         win->dpi = strtod(dpi_value, NULL);
         g_free(dpi_value);
     } else {
-        log_debug("Xrm query '%s' not found", "Xft.dpi");
+        log_debug("Xrm query '%s' not found", dpi_res);
         win->dpi = 96.0;
         //win->dpi = (double)screen_size->height * 25.4 / (double)screen_size->mheight;
-        log_debug("Fallback dpi value '%lf'", win->dpi);
+        log_debug("Fallback dpi value '%.2lf'", win->dpi);
     }
 }
 
@@ -330,6 +314,26 @@ void window_get_screen_size(Window *win, int *width, int *height)
     *height = win->screen_height;
 }
 
+void window_set_transparency(Window *win, double alpha)
+{
+    // Value between 0 and 1
+    g_assert_true(alpha >= 0 && alpha <= 1);
+    unsigned long opacity = 0xffffffff * alpha;
+
+    xcb_atom_t NET_WM_WINDOW_OPACITY = intern_atom(win, "_NET_WM_WINDOW_OPACITY");
+    xcb_change_property(win->connection,
+                        XCB_PROP_MODE_REPLACE,
+                        win->window,
+                        NET_WM_WINDOW_OPACITY,
+                        XCB_ATOM_CARDINAL,
+                        32,
+                        1,
+                        (char *)&opacity);
+
+    log_debug("Window transparency set to '%.2lf%%'", alpha * 100.0);
+
+}
+
 void window_move(Window *win, int x, int y)
 {
     if (win->x == x && win->y == y) return;
diff --git a/x11.h b/x11.h
index 3884485..b65310b 100644
--- a/x11.h
+++ b/x11.h
@@ -15,6 +15,8 @@ double window_get_scale(Window *win);
 
 void window_get_screen_size(Window *win, int *width, int *height);
 
+void window_set_transparency(Window *win, double alpha);
+
 void window_move(Window *win, int x, int y);
 
 void window_resize(Window *win, int width, int height);