[gnome-panel] background: remove fake transparency

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 78cfb7e3ca82d6118065f4b2490906242f9965ff
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Thu Oct 6 19:37:42 2016 +0300

    background: remove fake transparency

 gnome-panel/Makefile.am                |    2 -
 gnome-panel/panel-background-monitor.c |  388 --------------------------------
 gnome-panel/panel-background-monitor.h |   58 -----
 gnome-panel/panel-background.c         |  124 ++---------
 gnome-panel/panel-background.h         |    5 -
 5 files changed, 19 insertions(+), 558 deletions(-)
---
diff --git a/gnome-panel/Makefile.am b/gnome-panel/Makefile.am
index 68528f9..6debf16 100644
--- a/gnome-panel/Makefile.am
+++ b/gnome-panel/Makefile.am
@@ -33,7 +33,6 @@ panel_sources =                       \
        panel-applet-frame.c    \
        panel-applets-manager.c \
        panel-background.c      \
-       panel-background-monitor.c      \
        panel-stock-icons.c     \
        panel-action-button.c   \
        panel-image-menu-item.c \
@@ -81,7 +80,6 @@ panel_headers =                       \
        panel-applet-frame.h    \
        panel-applets-manager.h \
        panel-background.h      \
-       panel-background-monitor.h      \
        panel-stock-icons.h     \
        panel-action-button.h   \
        panel-image-menu-item.h \
diff --git a/gnome-panel/panel-background.c b/gnome-panel/panel-background.c
index 3ad300b..5b16f91 100644
--- a/gnome-panel/panel-background.c
+++ b/gnome-panel/panel-background.c
@@ -32,7 +32,6 @@
 
 #include <libpanel-util/panel-glib.h>
 
-#include "panel-background-monitor.h"
 #include "panel-schemas.h"
 #include "panel-util.h"
 
@@ -118,70 +117,17 @@ free_composited_resources (PanelBackground *background)
        background->composited_pattern = NULL;
 }
 
-static void
-background_changed (PanelBackgroundMonitor *monitor,
-                   PanelBackground        *background)
-{
-       GdkPixbuf *tmp;
-
-       tmp = background->desktop;
-
-       background->desktop = panel_background_monitor_get_region (
-                                       background->monitor,
-                                       background->region.x,
-                                       background->region.y,
-                                       background->region.width,
-                                       background->region.height);
-
-       if (tmp)
-               g_object_unref (tmp);
-
-       panel_background_composite (background);
-}
-
-// FIXMEchpe make this a cairo_pattern_t*
-static GdkPixbuf *
-get_desktop_pixbuf (PanelBackground *background)
-{
-       GdkPixbuf *desktop;
-
-       if (!background->monitor) {
-               background->monitor =
-                       panel_background_monitor_get_for_screen (
-                               gdk_window_get_screen (background->window));
-
-               background->monitor_signal =
-                       g_signal_connect (
-                       background->monitor, "changed",
-                        G_CALLBACK (background_changed), background);
-       }
-
-       desktop = panel_background_monitor_get_region (
-                               background->monitor,
-                               background->region.x,
-                               background->region.y,
-                               background->region.width,
-                               background->region.height);
-
-       return desktop;
-}
-
 static cairo_pattern_t *
 composite_image_onto_desktop (PanelBackground *background)
 {
        int              width, height;
+       GdkScreen       *screen;
        cairo_t         *cr;
        cairo_surface_t *surface;
        cairo_pattern_t *pattern;
 
-       if (!background->desktop)
-               background->desktop = get_desktop_pixbuf (background);
-
-       if (!background->desktop)
-               return NULL;
-
-       width  = gdk_pixbuf_get_width  (background->desktop);
-       height = gdk_pixbuf_get_height (background->desktop);
+       width  = background->region.width;
+       height = background->region.height;
 
         surface = gdk_window_create_similar_surface (background->window,
                                                      CAIRO_CONTENT_COLOR_ALPHA,
@@ -193,13 +139,12 @@ composite_image_onto_desktop (PanelBackground *background)
 
        cr = cairo_create (surface);
 
-        if (background->has_alpha) {
-                cairo_set_source_rgb (cr, 1, 1, 1);
-                cairo_paint (cr);
+        screen = gdk_screen_get_default ();
+        if (background->has_alpha && !gdk_screen_is_composited (screen)) {
+                GdkRGBA c = background->default_color;
 
-                gdk_cairo_set_source_pixbuf (cr, background->desktop, 0, 0);
-                cairo_rectangle (cr, 0, 0, width, height);
-                cairo_fill (cr);
+                cairo_set_source_rgb (cr, c.red, c.green, c.blue);
+                cairo_paint (cr);
         }
 
         gdk_cairo_set_source_pixbuf (cr, background->transformed_image, 0, 0);
@@ -218,15 +163,11 @@ composite_image_onto_desktop (PanelBackground *background)
 static cairo_pattern_t *
 composite_color_onto_desktop (PanelBackground *background)
 {
+        GdkScreen *screen;
         cairo_surface_t *surface;
         cairo_pattern_t *pattern;
         cairo_t *cr;
 
-        if (!background->desktop)
-                background->desktop = get_desktop_pixbuf (background);
-        if (!background->desktop)
-                return NULL;
-
         surface = gdk_window_create_similar_surface (background->window,
                                                      CAIRO_CONTENT_COLOR_ALPHA,
                                                      background->region.width,
@@ -237,11 +178,17 @@ composite_color_onto_desktop (PanelBackground *background)
         }
 
         cr = cairo_create (surface);
-        gdk_cairo_set_source_pixbuf (cr, background->desktop, 0, 0);
-        cairo_paint (cr);
 
-        gdk_cairo_set_source_rgba (cr, &background->color);
-        cairo_paint (cr);
+        screen = gdk_screen_get_default ();
+        if (!gdk_screen_is_composited (screen)) {
+                GdkRGBA c = background->color;
+
+                cairo_set_source_rgb (cr, c.red, c.green, c.blue);
+                cairo_paint (cr);
+        } else {
+                gdk_cairo_set_source_rgba (cr, &background->color);
+                cairo_paint (cr);
+        }
 
         cairo_destroy (cr);
 
@@ -473,22 +420,6 @@ panel_background_transform (PanelBackground *background)
 }
 
 static void
-disconnect_background_monitor (PanelBackground *background)
-{
-       if (background->monitor) {
-               g_signal_handler_disconnect (
-                       background->monitor, background->monitor_signal);
-               background->monitor_signal = -1;
-               g_object_unref (background->monitor);
-       }
-       background->monitor = NULL;
-
-       if (background->desktop)
-               g_object_unref (background->desktop);
-       background->desktop = NULL;
-}
-
-static void
 panel_background_update_has_alpha (PanelBackground *background)
 {
        gboolean has_alpha = FALSE;
@@ -500,9 +431,6 @@ panel_background_update_has_alpha (PanelBackground *background)
                has_alpha = gdk_pixbuf_get_has_alpha (background->loaded_image);
 
        background->has_alpha = has_alpha;
-
-       if (!has_alpha)
-               disconnect_background_monitor (background);
 }
 
 static void
@@ -829,10 +757,6 @@ panel_background_change_region (PanelBackground *background,
 
        background->orientation = orientation;
 
-       if (background->desktop)
-               g_object_unref (background->desktop);
-       background->desktop = NULL;
-
        if (need_to_retransform || ! background->transformed)
                /* only retransform the background if we have in
                   fact changed size/orientation */
@@ -874,10 +798,6 @@ panel_background_init (PanelBackground              *background,
        background->transformed_image  = NULL;
        background->composited_pattern = NULL;
 
-       background->monitor        = NULL;
-       background->desktop        = NULL;
-       background->monitor_signal = -1;
-
        background->window   = NULL;
 
        background->default_pattern     = NULL;
@@ -898,8 +818,6 @@ panel_background_init (PanelBackground              *background,
 void
 panel_background_free (PanelBackground *background)
 {
-       disconnect_background_monitor (background);
-
        free_transformed_resources (background);
 
        if (background->settings)
@@ -914,10 +832,6 @@ panel_background_free (PanelBackground *background)
                g_object_unref (background->loaded_image);
        background->loaded_image = NULL;
 
-       if (background->monitor)
-               g_object_unref (background->monitor);
-       background->monitor = NULL;
-
        if (background->window)
                g_object_unref (background->window);
        background->window = NULL;
diff --git a/gnome-panel/panel-background.h b/gnome-panel/panel-background.h
index b09e73f..48f94d9 100644
--- a/gnome-panel/panel-background.h
+++ b/gnome-panel/panel-background.h
@@ -28,7 +28,6 @@
 
 #include "panel-enums.h"
 #include "panel-types.h"
-#include "panel-background-monitor.h"
 
 typedef struct _PanelBackground PanelBackground;
 
@@ -53,10 +52,6 @@ struct _PanelBackground {
         GdkPixbuf              *transformed_image;
        cairo_pattern_t        *composited_pattern;
 
-       PanelBackgroundMonitor *monitor;
-       GdkPixbuf              *desktop;
-       gulong                  monitor_signal;
-
        GdkWindow              *window;
 
        cairo_pattern_t        *default_pattern;