GNOME Bugzilla – Bug 457529
suggest pre-loading thumbnails
Last modified: 2009-09-10 19:45:29 UTC
scrolling through a lot of thumbnails is visually frustrating, it seems that it is only as new thumbnail tiles scroll into view, that the thumbnails themselves get loaded into the frames, so scrolling up and down quickly you see a lot of blank tiles at first. Compare to gqview where the thumbnails pre-load whenever you change folder. Once they're loaded, scrolling reveals the already loaded thumbnails. Combining both behaviours should provide a further improvement for users. Might this be a fairly easy enhancement to deploy? Thanks. Other information:
gThumb makes thumbnails for all images in the folder, and stores them (as files) in the thumbnail cache. The thumbnails for the visible images are kept in memory. The non-visible ones are not, to save memory. However, I've made a change in trunk to keep the visible thumbnails in memory, plus 200 before and 200 after the visible range. Can you try compiling from svn trunk and see if it seems more responsive? - Mike
Mike, thanks for the fast turn around. I'm sorry, but as far as compiling trunks etc goes I'm at newbie level zero.. yum is as close as I've got to trying programs. Perhaps someone else will be able to compile for testing? Jacek
Jacek, It's not hard to compile. I'll tell you how, step by step. Please install svn on your system ("yum install svn") and then do this: cd ~ svn checkout http://svn.gnome.org/svn/gthumb/trunk cd trunk ./autogen.sh --prefix=/usr make su make install exit gthumb The above sequence is suitable for Red Hat and Fedora type systems. If you want developers to implement your feature requests, it is very helpful if you can test the new features... - Mike
Thanks Mike. I gave it a go as follows: ~]$ su -c 'yum -y install svn' Password: Loading "installonlyn" plugin Setting up Install Process Parsing package install arguments fedora 100% |=========================| 2.1 kB 00:00 updates 100% |=========================| 1.9 kB 00:00 primary.sqlite.bz2 100% |=========================| 980 kB 00:05 Nothing to do so I installed 'svncpp' and 'svncpp-devel' instead as they looked similar! ..and then it wanted 'gnome-common.noarch 0:2.12.0-4.fc7' so I installed that as well then ran: ./autogen.sh --prefix=/usr which returned: ***Error***: some autoconf macros required to build gThumb were not found in your aclocal path, or some forbidden macros were found. Perhaps you need to adjust your ACLOCAL_FLAGS? At which point I gave up... All the best Jacek
Jacek, When yum says "Nothing to do", that means svn was already installed, which is fine. The other error just means that some development libraries are missing. Try installing them using: yum install gtk2-devel glib*devel intltool libxml2-devel libgnome-devel libgnomeui-devel libgnomecanvas-devel gnome-vfs2-devel libglade2-devel libexif-devel libjpeg-devel libtiff-devel Then try "./autogen.sh --prefix=/usr" again. Fun, eh? - Mike
Mike, Fun indeed (not!) but rewarding. First the bad news - did the above - same or similar error messages as before. The good news is I went and installed every developer-like app and library I could find. .. and then it worked. So down to the testing. Everything seemed to go well on a folder with a few screen-fulls of icons. When I tried it on a much larger folder was there still the previous issue (but less so than before). The problem was because I was scrolling more than the 200 at a time. So in search of perfection, might it be possible to provide a user option to set the size (in number of thumbnails) to read ahead and behind the current location? That way you can tailor it to your needs and to your kit. My PC is 2GHZ with 512 KB ram, so it does beg the question of what it would be like on slower kit. A user-set option might be the answer? Or you could have the gthumb calculate an optimum for the user instead. Just thoughts.. If I have time at the weekend I'll try and use it some more in case there's some unexpected knock on effect. Thanks Jacek