netrender

Bugfix for job cancellation (reported by Carsten in email)
Ended up recoding part of the communication pipe (use json more consistently)
Fix bpy data modifications where it shouldn't happen (as a bonus, thumbnailing is now done out of process)

release/scripts/io/netrender/thumbnail.py

@@ -0,0 +1,81 @@
+# ##### BEGIN GPL LICENSE BLOCK #####
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU General Public License
+#  as published by the Free Software Foundation; either version 2
+#  of the License, or (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, write to the Free Software Foundation,
+#  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# ##### END GPL LICENSE BLOCK #####
+
+import sys, os
+import subprocess
+
+import bpy
+
+def generate(filename, external=True):
+    if external:
+        process = subprocess.Popen([sys.argv[0], "-b", "-noaudio", "-P", __file__, "--", filename], stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+        while process.poll() is None:
+            process.stdout.read(1024) # empty buffer to be sure
+        process.stdout.read()
+        
+        return _thumbname(filename)
+    else:
+        return _internal(filename)
+
+def _thumbname(filename):
+    root = os.path.splitext(filename)[0]
+    return root + ".jpg"
+
+def _internal(filename):
+    imagename = os.path.split(filename)[1]
+    thumbname = _thumbname(filename)
+
+    if os.path.exists(thumbname):
+        return thumbname
+
+    if bpy:
+        scene = bpy.data.scenes[0] # FIXME, this is dodgy!
+        scene.render.file_format = "JPEG"
+        scene.render.file_quality = 90
+        
+        # remove existing image, if there's a leftover (otherwise open changes the name)
+        if imagename in bpy.data.images:
+            img = bpy.data.images[imagename]
+            bpy.data.images.remove(img)
+
+        bpy.ops.image.open(filepath=filename)
+        img = bpy.data.images[imagename]
+            
+        img.save_render(thumbname, scene=scene)
+        
+        img.user_clear()
+        bpy.data.images.remove(img)
+
+        try:
+            process = subprocess.Popen(["convert", thumbname, "-resize", "300x300", thumbname])
+            process.wait()
+            return thumbname
+        except Exception as exp:
+            print("Error while generating thumbnail")
+            print(exp)
+
+    return None
+
+if __name__ == "__main__":
+    import bpy
+    try:
+        start = sys.argv.index("--") + 1
+    except ValueError:
+        start = 0
+    for filename in sys.argv[start:]:
+        generate(filename, external=False)