from Jesse Kaukonen (gekko)
--- text from the patch.
Recently Campbell Barton added callback functionality for Python's usage, but this only includes pre- and post-render callbacks. There are no callbacks for the duration of the render. This patch adds the few lines required for executing a callback while Blender Render is working. The callback resides in the rendering pipeline stats function, so whenever statistics are printed, the callback is executed. This functionality is required if one wants to:
1) Observe what is happening while Blender is rendering via the command line
2) Add custom statistics that Blender prints while the renderer works
3) The user wants to continue executing his Python script without the code halting at bpy.ops.render.render()
Personally I'm currently using this for printing out more detailed progress reports at Renderfarm.fi (such as CPU time, time spent rendering, total progress in regards to the entire rendering process). Tested on Windows, Linux and OS X.
Example on how to use the callback:
def statscall(context): print("Thanks for calling!")
bpy.app.handlers.render_stats.append(statscall)
bpy.ops.render.render(animation=False, write_still=True)
Python:
* adds bpy.app.handlers which contains lists, each for an event type:
render_pre, render_post, load_pre, load_post, save_pre, save_post
* each list item needs to be a callable object which takes 1 argument (the ID).
* callbacks are cleared on file load.
Example:
def MyFunc(scene): print("Callback:", data)
bpy.app.handlers.render_post.append(MyFunc)
C:
* This patch adds a generic C callback api which is currently only used by python.
* Unlike python callbacks these are not cleared on file load.
