Don't show thumbnails for small zoom levels

When the zoom level is too small, thumbnails become useless, as they are
so small that they don't give any information.

The solution to this problem is to use mimetype icons when the zoom
level is too small

In order to achieve this, there was added a function that returns
false if the zoom is too small, nautilus_thumbnail_is_limited_by_zoom.
Therefore, if it returns false, the mimetype icon will be used.

https://bugzilla.gnome.org/show_bug.cgi?id=752805

2 files changed, 23 insertions, 1 deletions

diff --git a/libnautilus-private/nautilus-file.c b/libnautilus-private/nautilus-file.c
index 22e29ddd8..8bdfcfd96 100644
--- a/libnautilus-private/nautilus-file.c
+++ b/libnautilus-private/nautilus-file.c
@@ -4581,6 +4581,24 @@ nautilus_file_get_thumbnail_icon (NautilusFile *file,
 	return icon;
 }
 
+gboolean nautilus_thumbnail_is_limited_by_zoom (int size, int scale,
+						 NautilusFileIconFlags flags)
+{
+	int zoom_level;
+
+	if (flags & NAUTILUS_FILE_ICON_FLAGS_FORCE_THUMBNAIL_SIZE) {
+		zoom_level = size * scale;
+	} else {
+		zoom_level = size * scale *
+			     cached_thumbnail_size / NAUTILUS_CANVAS_ICON_SIZE_SMALL;
+	}
+
+	if (zoom_level <= NAUTILUS_LIST_ICON_SIZE_SMALL)
+		return FALSE;
+
+	return TRUE;
+}
+
 NautilusIconInfo *
 nautilus_file_get_icon (NautilusFile *file,
 			int size,
@@ -4608,7 +4626,8 @@ nautilus_file_get_icon (NautilusFile *file,
 	       flags & NAUTILUS_FILE_ICON_FLAGS_FORCE_THUMBNAIL_SIZE);
 
 	if (flags & NAUTILUS_FILE_ICON_FLAGS_USE_THUMBNAILS &&
-	    nautilus_file_should_show_thumbnail (file)) {
+	    nautilus_file_should_show_thumbnail (file) &&
+	    nautilus_thumbnail_is_limited_by_zoom (size, scale, flags)) {
 		icon = nautilus_file_get_thumbnail_icon (file, size, scale, flags);
 	}
 
diff --git a/libnautilus-private/nautilus-file.h b/libnautilus-private/nautilus-file.h
index 363fbff38..a6a657ed2 100644
--- a/libnautilus-private/nautilus-file.h
+++ b/libnautilus-private/nautilus-file.h
@@ -210,6 +210,9 @@ NautilusRequestStatus   nautilus_file_get_deep_counts                   (Nautilu
 									 gboolean                        force);
 gboolean                nautilus_file_should_show_thumbnail             (NautilusFile                   *file);
 gboolean                nautilus_file_should_show_directory_item_count  (NautilusFile                   *file);
+gboolean 		 nautilus_thumbnail_is_limited_by_zoom		 (int 				 size,
+									  int 				 scale,
+									  NautilusFileIconFlags 	 flags);
 
 void                    nautilus_file_set_search_relevance              (NautilusFile                   *file,
 									 gdouble                         relevance);