[nautilus] nautilus-file: Don't show thumbnails for small zoom levels

[Carlos Soriano Sánchez <csoriano src gnome org>]

commit 7059cc66ca3bc338e49a6ac4cb37c3484ba3b19d
Author: Alexandru Pandelea <alexandru pandelea gmail com>
Date:   Thu Mar 3 07:30:43 2016 +0200

    nautilus-file: 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
    true if the zoom is too small, nautilus_thumbnail_is_limited_by_zoom,
    meaning that the corresponding mimetype icon should be used instead
    of the thumbnail
    
    https://bugzilla.gnome.org/show_bug.cgi?id=752805

 libnautilus-private/nautilus-file.c |   17 ++++++++++++++++-
 1 files changed, 16 insertions(+), 1 deletions(-)
---
diff --git a/libnautilus-private/nautilus-file.c b/libnautilus-private/nautilus-file.c
index 22e29dd..1efe626 100644
--- a/libnautilus-private/nautilus-file.c
+++ b/libnautilus-private/nautilus-file.c
@@ -4581,6 +4581,20 @@ nautilus_file_get_thumbnail_icon (NautilusFile *file,
        return icon;
 }
 
+static gboolean
+nautilus_thumbnail_is_limited_by_zoom (int size,
+                                      int scale)
+{
+       int zoom_level;
+
+       zoom_level = size * scale;
+
+       if (zoom_level <= NAUTILUS_LIST_ICON_SIZE_SMALL)
+               return TRUE;
+
+       return FALSE;
+}
+
 NautilusIconInfo *
 nautilus_file_get_icon (NautilusFile *file,
                        int size,
@@ -4608,7 +4622,8 @@ 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)) {
                icon = nautilus_file_get_thumbnail_icon (file, size, scale, flags);
        }