Merge lp:~donadigo/pantheon-greeter/fix-black-bars into lp:~elementary-pantheon/pantheon-greeter/trunk

[Adam Bieńkowski]

* Fix black bars appearing to users on login screen.

Fixes black bars appearing to users on login screen.

This branch uses the Ubuntu's Unity Greeter algorithm that is easier to understand and also fixes the problem with black bars.

[Danielle Foré (danrabbit)]

Looks good! Thanks :D

review: Approve

=== modified file 'src/Wallpaper.vala'
--- src/Wallpaper.vala	2016-06-14 12:38:50 +0000
+++ src/Wallpaper.vala	2016-06-14 21:40:30 +0000
@@ -98,15 +98,17 @@
                 cache_path += path;
                 cache_pixbuf += buf;
                 background_pixbuf = buf;
+            } else {
+                buf = validate_pixbuf (buf);
             }
-            //check if the currently loaded wallpaper is the one we loaded in this method
+
+            // check if the currently loaded wallpaper is the one we loaded in this method
             if (last_loaded != path) {
                 return; //if not, abort
             }
 
             var new_wallpaper = make_image ();
             new_wallpaper.pixbuf = buf;
-            resize (new_wallpaper);
             stack.add (new_wallpaper);
             stack.show_all ();
             stack.visible_child = new_wallpaper;
@@ -178,45 +180,24 @@
      * screen size to save memory.
      */
     Gdk.Pixbuf validate_pixbuf (Gdk.Pixbuf pixbuf) {
-        var result = scale_to_rect (pixbuf, gpu_limit, gpu_limit);
-        result = scale_to_rect (pixbuf, screen_width, screen_height);
-        return result;
+        return scale_to_rect (pixbuf, screen_width, screen_height);
     }
 
     Gdk.Pixbuf scale_to_rect (Gdk.Pixbuf pixbuf, int rect_width, int rect_height) {
-        int height = pixbuf.height;
-        int width = pixbuf.width;
-
-        if (height > rect_height || width > rect_width) {
-            float hw = (float)height / width * rect_width;
-            float wh = (float)width / height * rect_height;
-            if (height < width) {
-                return pixbuf.scale_simple (rect_width, (int) (hw), Gdk.InterpType.BILINEAR);
-            } else {
-                return pixbuf.scale_simple ((int) (wh), rect_height, Gdk.InterpType.BILINEAR);
-            }
-        }
-        return pixbuf;
-    }
-
-    void resize (Gtk.Image image) {
-        int w, h;
-
-        w = image.width_request;
-        h = image.height_request;
-
-
-        if (width > (w * height) / h) {
-            image.width_request = (int) width;
-            image.height_request = (int) (h * width / w);
-
-            if (height > image.height_request) {
-                image.height_request = (int) height;
-                image.width_request = (int) (w * height / h);
-            }
+        double target_aspect = (double) rect_width / rect_height;
+        double aspect = (double) pixbuf.width / pixbuf.height;
+        double scale, offset_x = 0, offset_y = 0;
+        if (aspect > target_aspect) {
+            scale = (double) rect_height / pixbuf.height;
+            offset_x = (pixbuf.width * scale - rect_width) / 2;
         } else {
-            image.height_request = (int) height;
-            image.width_request = (int) (w * height / h);
+            scale = (double) rect_width / pixbuf.width;
+            offset_y = (pixbuf.height * scale - rect_height) / 2;
         }
+
+        var scaled_pixbuf = new Gdk.Pixbuf (pixbuf.colorspace, pixbuf.has_alpha, pixbuf.bits_per_sample, rect_width, rect_height);
+        pixbuf.scale (scaled_pixbuf, 0, 0, rect_width, rect_height, -offset_x, -offset_y, scale, scale, Gdk.InterpType.BILINEAR);
+
+        return scaled_pixbuf;
     }
 }