Pause filters before taking screenshots

data/shaders/colorblindness-correction.vert

@@ -8,9 +8,16 @@
 uniform sampler2D tex;
 uniform int COLORBLIND_MODE;
 uniform float STRENGTH;
+uniform bool PAUSE_FOR_SCREENSHOT;
+
 void main() {
     vec4 c = texture2D(tex, cogl_tex_coord0_in.xy);
 
+    if (PAUSE_FOR_SCREENSHOT) {
+        cogl_color_out = c;
+        return;
+    }
+
     // RGB to LMS matrix
     float L = (17.8824f * c.r) + (43.5161f * c.g) + (4.11935f * c.b);
     float M = (3.45565f * c.r) + (27.1554f * c.g) + (3.86714f * c.b);

data/shaders/monochrome.vert

@@ -5,9 +5,16 @@
 
 uniform sampler2D tex;
 uniform float STRENGTH;
+uniform bool PAUSE_FOR_SCREENSHOT;
+
 void main() {
-    vec2 uv = cogl_tex_coord0_in.xy;
-    vec4 sample = texture2D (tex, uv);
+    vec4 sample = texture2D (tex, cogl_tex_coord0_in.xy);
+
+    if (PAUSE_FOR_SCREENSHOT) {
+        cogl_color_out = sample;
+        return;
+    }
+
     vec3 luminance = vec3 (0.2126, 0.7512, 0.0722);
     float gray = luminance.r * sample.r + luminance.g * sample.g + luminance.b * sample.b;
     cogl_color_out = vec4 (

src/ColorFilters/ColorblindnessCorrectionEffect.vala

@@ -19,11 +19,16 @@ public class Gala.ColorblindnessCorrectionEffect : Clutter.ShaderEffect {
         get { return _strength; }
         construct set {
             _strength = value;
-
             set_uniform_value ("STRENGTH", value);
             queue_repaint ();
         }
     }
+    public bool pause_for_screenshot {
+        set {
+            set_uniform_value ("PAUSE_FOR_SCREENSHOT", (int) value);
+            queue_repaint ();
+        }
+    }
 
     /*
      * Used for fading in and out the effect, since you can't add transitions to effects.
@@ -47,5 +52,7 @@ public class Gala.ColorblindnessCorrectionEffect : Clutter.ShaderEffect {
         } catch (Error e) {
             critical ("Unable to load colorblindness-correction.vert: %s", e.message);
         }
+
+        pause_for_screenshot = false;
     }
 }

src/ColorFilters/FilterManager.vala

@@ -7,19 +7,25 @@ public class Gala.FilterManager : Object {
     private const string TRANSITION_NAME = "strength-transition";
     private const int TRANSITION_DURATION = 500;
 
-    private static FilterManager instance;
-    private static GLib.Settings settings;
     public WindowManager wm { get; construct; }
 
-    public static void init (WindowManager wm) {
-        if (instance != null) {
-            return;
+    public bool pause_for_screenshot {
+        set {
+            foreach (unowned var _effect in wm.stage.get_effects ()) {
+                if (_effect is ColorblindnessCorrectionEffect) {
+                    unowned var effect = (ColorblindnessCorrectionEffect) _effect;
+                    effect.pause_for_screenshot = value;
+                } else if (_effect is MonochromeEffect) {
+                    unowned var effect = (MonochromeEffect) _effect;
+                    effect.pause_for_screenshot = value;
+                }
+            }
         }
-
-        instance = new FilterManager (wm);
     }
 
-    private FilterManager (WindowManager wm) {
+    private static GLib.Settings settings;
+
+    public FilterManager (WindowManager wm) {
         Object (wm: wm);
     }
 

src/ColorFilters/MonochromeEffect.vala

@@ -11,11 +11,16 @@ public class Gala.MonochromeEffect : Clutter.ShaderEffect {
         get { return _strength; }
         construct set {
             _strength = value;
-
             set_uniform_value ("STRENGTH", value);
             queue_repaint ();
         }
     }
+    public bool pause_for_screenshot {
+        set {
+            set_uniform_value ("PAUSE_FOR_SCREENSHOT", (int) value);
+            queue_repaint ();
+        }
+    }
 
     /*
      * Used for fading in and out the effect, since you can't add transitions to effects.
@@ -38,5 +43,7 @@ public class Gala.MonochromeEffect : Clutter.ShaderEffect {
         } catch (Error e) {
             critical ("Unable to load monochrome.vert: %s", e.message);
         }
+
+        pause_for_screenshot = false;
     }
 }

src/ScreenshotManager.vala

@@ -14,6 +14,8 @@ public class Gala.ScreenshotManager : Object {
     public WindowManager wm { get; construct; }
     [DBus (visible = false)]
     public NotificationsManager notifications_manager { get; construct; }
+    [DBus (visible = false)]
+    public FilterManager filter_manager { get; construct; }
 
     private bool? _is_redacted_font_available = null;
     private bool is_redacted_font_available {
@@ -45,8 +47,8 @@ public class Gala.ScreenshotManager : Object {
     private string prev_font_mono;
     private uint conceal_timeout;
 
-    public ScreenshotManager (WindowManager wm, NotificationsManager notifications_manager) {
-        Object (wm: wm, notifications_manager: notifications_manager);
+    public ScreenshotManager (WindowManager wm, NotificationsManager notifications_manager, FilterManager filter_manager) {
+        Object (wm: wm, notifications_manager: notifications_manager, filter_manager: filter_manager);
     }
 
     construct {
@@ -266,8 +268,13 @@ public class Gala.ScreenshotManager : Object {
         int width, height;
         display.get_size (out width, out height);
 
+        filter_manager.pause_for_screenshot = true;
+
+        yield wait_stage_repaint ();
+
         var image = take_screenshot (0, 0, width, height, include_cursor);
         unconceal_text ();
+        filter_manager.pause_for_screenshot = false;
 
         if (flash) {
             flash_area (0, 0, width, height);
@@ -288,10 +295,13 @@ public class Gala.ScreenshotManager : Object {
     public async void screenshot_area_with_cursor (int x, int y, int width, int height, bool include_cursor, bool flash, string filename, out bool success, out string filename_used) throws DBusError, IOError {
         debug ("Taking area screenshot");
 
+        filter_manager.pause_for_screenshot = true;
+
         yield wait_stage_repaint ();
 
         var image = take_screenshot (x, y, width, height, include_cursor);
         unconceal_text ();
+        filter_manager.pause_for_screenshot = false;
 
         if (flash) {
             flash_area (x, y, width, height);

src/WindowManager.vala

@@ -79,6 +79,8 @@ namespace Gala {
 
         public WindowTracker? window_tracker { get; private set; }
 
+        private FilterManager filter_manager;
+
         private NotificationsManager notifications_manager;
 
         private ScreenshotManager screenshot_manager;
@@ -133,6 +135,12 @@ namespace Gala {
 
             AccessDialog.watch_portal ();
 
+
+            filter_manager = new FilterManager (this);
+            notifications_manager = new NotificationsManager ();
+            screenshot_manager = new ScreenshotManager (this, notifications_manager, filter_manager);
+            DBus.init (this, notifications_manager, screenshot_manager);
+
             unowned Meta.Display display = get_display ();
             display.gl_video_memory_purged.connect (() => {
                 Meta.Background.refresh_all ();
@@ -173,10 +181,6 @@ namespace Gala {
         private void show_stage () {
             unowned Meta.Display display = get_display ();
 
-            notifications_manager = new NotificationsManager ();
-            screenshot_manager = new ScreenshotManager (this, notifications_manager);
-            DBus.init (this, notifications_manager, screenshot_manager);
-
             WindowListener.init (display);
             keyboard_manager = new KeyboardManager (display);
             window_tracker = new WindowTracker ();
@@ -301,8 +305,6 @@ namespace Gala {
             // is set to NONE when we are in locked mode
             screensaver.active_changed.connect (update_input_area);
 
-            FilterManager.init (this);
-
             /*keybindings*/
             var keybinding_settings = new GLib.Settings ("io.elementary.desktop.wm.keybindings");