gschem file preview function renders files twice

[thepurlieu]

Just a minor observation here...nothing big.

After opening the "open file" dialog and clicking on a schematic file, the preview window to the right renders everything twice. This is quite noticeable on some of my monster schematics...you have to wait for it to flash the rendered image two times before you can click on another file.

Maybe the preview code is getting a duplicate signal from the file window? Or maybe this is actually a GTK+ bug in the file chooser widget...I'm not sure.

Cheers--
Julian

[Peter Clifton (pcjc2)]

I can't reproduce this with GTK 2.12. What version do you have?

I instrumented with this patch in x_fileselect.c:

diff --git a/gschem/src/x_fileselect.c b/gschem/src/x_fileselect.c
index bdf8188..84a9e98 100644
--- a/gschem/src/x_fileselect.c
+++ b/gschem/src/x_fileselect.c
@@ -91,6 +91,8 @@ x_fileselect_callback_update_preview (GtkFileChooser *chooser,
     preview_filename = filename;
   }

+ printf ("Updating file preview widget\n");
+
   /* update preview */
   g_object_set (preview,
                 "filename", preview_filename,

and only get one update per file clicked.

It would be helpful if you could check and see what your box does. If it turns out to be a GTK bug, we might be able to work around it by checking whether the current preview filename matches the new one being set.

[thepurlieu (thepurlieu-users)]

Peter,
   I'm running 2.12 as well. Looking more into the problem...it only seems to do the double-refresh if you are browsing through files in the same directory (if you change directory, it only refreshes once for the first file that comes up). It double-refreshes the first time you open the file chooser window.
    I put some debug messages into the gschem code exactly where you did, and it is only being called once, even though I can see it being drawn twice on the screen. Could it be doing a double refresh inside the preview object handler somehow (I'm not sure where that is in the gschem code...)? I vaguely remember reading a post from you talking about double-buffering the gschem draws...could that be somehow related?

Cheers--

[Peter TB Brett (peter-b)]

I can reproduce this with the following patch.

diff --git a/gschem/src/x_preview.c b/gschem/src/x_preview.c
index be76d64..60f88fc 100644
--- a/gschem/src/x_preview.c
+++ b/gschem/src/x_preview.c
@@ -131,6 +131,7 @@ preview_callback_expose (GtkWidget *widget,
   preview_w_current->pl = pango_cairo_create_layout (preview_w_current->cr);

   gdk_region_get_rectangles (event->region, &rectangles, &n_rectangles);
+ g_debug ("Preview redraw");
   o_redraw_rects (preview_w_current, rectangles, n_rectangles);
   g_free (rectangles);

[Vladimir Zhbanov (vzhbanov)]

Hi all,
I could not reproduce this bug neither for 1.8.0 nor for the current git master head.
So I believe its status should be changed to "Fix commited".
Any objections?

[Vladimir Zhbanov (vzhbanov)]

OK, to check if the bug is now solved, I've made a big schematic
and chosen it in the file open dialog. While it takes more time to
show its contents compared with small schematics, it renders
anything once now. Therefore I close this as `committed' since I
don't know when it was solved.

[Roland Lutz (rlutz)]

released in gEDA/gaf 1.10.0