nukecontexts

nukecontexts is a library of composable context managers for Nuke to manage the state of complex compositing scripts in code.

Full Documentation

Installation

To install nukecontexts, type:

$ pip install nukecontexts

Open Nuke's init.py file and add:

nuke.pluginAddPath('/path/to/your/local/python/site-packages')

Getting Started

The most common use case for nukecontexts is automated rendering of multiple states of a compositing script. For example two different output formats, jpg and png.

import nuke
import contextlib
from nukecontexts import ctx

render_node = nuke.toNode('Write1')
with ctx.set_attr(render_node, 'file_type', 'jpeg'):
    nuke.execute(render_node.name(), 1, 1, 1)
with ctx.set_attr(render_node, 'file_type', 'png'):
    nuke.execute(render_node.name(), 1, 1, 1)

The power of nukecontexts comes with composable contexts, using contextlib.nested(). Arbitrarily complex, varying states of the compositing script can be defined and used to automatically generate different results.

merge_node = nuke.toNode('Merge1')
grade_node = nuke.toNode('Grade1')
switch_node = nuke.toNode('Switch1')

ctx1 = ctx.enable([merge_node, grade_node])
ctx2 = ctx.set_attr(grade_node, 'white', 2.0)
ctx3 = ctx.set_attr(switch_node, 'which', 0)
ctx4 = ctx.disable(merge_node)

with contextlib.nested(ctx1, ctx2, ctx3):
    """Render with the merge_node and grade_node enabled, the
    grade_node's white attribute set to 2.0 and the switch_node's switch
    position set to 0."""
    nuke.execute(render_node.name(), 1, 1, 1)

with contextlib.nested(ctx3, ctx4):
    """Render with the switch_node's switch position set to 0 and the
    merge node disabled; the grade_node's gain value remains at the
    original value."""
    nuke.execute(render_node.name(), 1, 1, 1)