background: Use monitor scale to generate the texture at real monitor size

We need to use pixel size of the monitor in order to generate a valid
texture with full quality for current monitor

In spanned case the background should cover all the differently scaled monitors
thus we scale the texture up to the maximum scaling level and then we resample
it drawing only each side in the monitor it should occupy using the proper
scaling level.

In wallpaper mode (or color mode) for example we don't need to scale the area,
also the texture size we return should be unscaled, not to confuse
MetaBackgroundActor making it use more space than needed.

https://bugzilla.gnome.org/show_bug.cgi?id=765011

1 files changed, 25 insertions, 11 deletions

diff --git a/src/compositor/meta-background.c b/src/compositor/meta-background.c
index f06d54245..6dd4242d2 100644
--- a/src/compositor/meta-background.c
+++ b/src/compositor/meta-background.c
@@ -370,6 +370,7 @@ set_texture_area_from_monitor_area (cairo_rectangle_int_t *monitor_area,
 static void
 get_texture_area (MetaBackground          *self,
                   cairo_rectangle_int_t   *monitor_rect,
+                  float                    monitor_scale,
                   CoglTexture             *texture,
                   cairo_rectangle_int_t   *texture_area)
 {
@@ -394,7 +395,7 @@ get_texture_area (MetaBackground          *self,
       meta_display_get_size (self->display, &screen_width, &screen_height);
 
       /* Start off by centering a tile in the middle of the
-       * total screen area.
+       * total screen area taking care of the monitor scaling.
        */
       image_area.x = (screen_width - texture_width) / 2.0;
       image_area.y = (screen_height - texture_height) / 2.0;
@@ -462,9 +463,9 @@ get_texture_area (MetaBackground          *self,
          */
         meta_display_get_size (self->display, &screen_width, &screen_height);
 
-        /* unclipped texture area is whole screen */
-        image_area.width = screen_width;
-        image_area.height = screen_height;
+        /* unclipped texture area is whole screen, scaled depending on monitor */
+        image_area.width = screen_width * monitor_scale;
+        image_area.height = screen_height * monitor_scale;
 
         /* But make (0,0) line up with the appropriate monitor */
         image_area.x = -monitor_rect->x;
@@ -481,12 +482,13 @@ draw_texture (MetaBackground        *self,
               CoglFramebuffer       *framebuffer,
               CoglPipeline          *pipeline,
               CoglTexture           *texture,
-              cairo_rectangle_int_t *monitor_area)
+              cairo_rectangle_int_t *monitor_area,
+              float                  monitor_scale)
 {
   cairo_rectangle_int_t texture_area;
   gboolean bare_region_visible;
 
-  get_texture_area (self, monitor_area, texture, &texture_area);
+  get_texture_area (self, monitor_area, monitor_scale, texture, &texture_area);
 
   switch (self->style)
     {
@@ -728,6 +730,7 @@ meta_background_get_texture (MetaBackground         *self,
   MetaRectangle geometry;
   cairo_rectangle_int_t monitor_area;
   CoglTexture *texture1, *texture2;
+  float monitor_scale;
 
   g_return_val_if_fail (META_IS_BACKGROUND (self), NULL);
   g_return_val_if_fail (monitor_index >= 0 && monitor_index < self->n_monitors, NULL);
@@ -735,6 +738,7 @@ meta_background_get_texture (MetaBackground         *self,
   monitor = &self->monitors[monitor_index];
 
   meta_display_get_monitor_geometry (self->display, monitor_index, &geometry);
+  monitor_scale = meta_display_get_monitor_scale (self->display, monitor_index);
   monitor_area.x = geometry.x;
   monitor_area.y = geometry.y;
   monitor_area.width = geometry.width;
@@ -758,8 +762,8 @@ meta_background_get_texture (MetaBackground         *self,
       ensure_wallpaper_texture (self, texture1))
     {
       if (texture_area)
-        get_texture_area (self, &monitor_area, self->wallpaper_texture,
-                          texture_area);
+        get_texture_area (self, &monitor_area, monitor_scale,
+                          self->wallpaper_texture, texture_area);
       if (wrap_mode)
         *wrap_mode = COGL_PIPELINE_WRAP_MODE_REPEAT;
       return self->wallpaper_texture;
@@ -770,6 +774,14 @@ meta_background_get_texture (MetaBackground         *self,
       CoglError *catch_error = NULL;
       gboolean bare_region_visible = FALSE;
 
+      if (self->style != G_DESKTOP_BACKGROUND_STYLE_WALLPAPER)
+        {
+          monitor_area.x *= monitor_scale;
+          monitor_area.y *= monitor_scale;
+          monitor_area.width *= monitor_scale;
+          monitor_area.height *= monitor_scale;
+        }
+
       if (monitor->texture == NULL)
         {
           CoglOffscreen *offscreen;
@@ -809,7 +821,8 @@ meta_background_get_texture (MetaBackground         *self,
 
           bare_region_visible = draw_texture (self,
                                               monitor->fbo, pipeline,
-                                              texture2, &monitor_area);
+                                              texture2, &monitor_area,
+                                              monitor_scale);
 
           cogl_object_unref (pipeline);
         }
@@ -833,7 +846,8 @@ meta_background_get_texture (MetaBackground         *self,
 
           bare_region_visible = bare_region_visible || draw_texture (self,
                                                                      monitor->fbo, pipeline,
-                                                                     texture1, &monitor_area);
+                                                                     texture1, &monitor_area,
+                                                                     monitor_scale);
 
           cogl_object_unref (pipeline);
         }
@@ -855,7 +869,7 @@ meta_background_get_texture (MetaBackground         *self,
     }
 
   if (texture_area)
-    set_texture_area_from_monitor_area (&monitor_area, texture_area);
+    set_texture_area_from_monitor_area (&geometry, texture_area);
 
   if (wrap_mode)
     *wrap_mode = COGL_PIPELINE_WRAP_MODE_CLAMP_TO_EDGE;