[Bf-codereview] Multi File Output Node (issue 5666047)

[lukas.toenne at googlemail.com]

I have implemented the changes discussed so far.

1) Old CMP_NODE_OUTPUT_FILE and CMP_NODE_OUTPUT_MULTI_FILE have been
merged, only CMP_NODE_OUTPUT_FILE remains. All functions renamed
accordingly.

2) do_versions code for converting single-file output nodes into
multi-file output nodes. If a Z buffer input is used, the node is made
into a multilayer exr with two inputs. (see below). Also re-identifies
multi-file output nodes with the CMP_NODE_OUTPUT_FILE type.

3) "Global" format is stored in node now. By default this overrides any
per-socket settings.

4) Multilayer EXR output implemented. When M.EXR format is selected for
node format, all socket format details are ignored. Socket names are
used for layer names.

5) Input buffer types are used as-is when possible, i.e. stored as B/W,
RGB or RGBA. In regular file output the format dictates the number of
actual channels, so the CompBuf is typechecked to the right type first.
For multilayer EXR the number of channels is more flexible, so an input
buffer will store only the channels it actually uses.

6) The editor socket type is updated from linked sockets as an indicator
of the actual data written to files. This may not be totally accurate
for regular file output though, due to restrictions of format setting.

http://codereview.appspot.com/5666047/