Baking Sverchok animation to Shape Keys (Script)

[vicdoval]

I wanted to share this little script for Blender 2.79 to bake Sverchok animations to Shape Keys
This allows to have smooth motion blur, very fast viewport animation, sending it to a render farm or to render the output animation it in 2.8
It works by creating a copy of the selected object and adding every frame a new keyframed Shape Key

To use it just paste it in a text-block, select the original object and hit 'Run the script'

import bpy

original_name = bpy.context.active_object.name
first_frame = bpy.context.scene.frame_start 
end_frame = bpy.context.scene.frame_end 
bpy.context.scene.frame_current = first_frame
bpy.ops.node.sverchok_update_all()
bpy.ops.object.duplicate()
bpy.context.active_object.name = 'Baked_' + original_name
bpy.context.active_object.data.name = 'Baked_' + original_name
bpy.data.objects[original_name].select = True
bpy.ops.object.join_shapes()
for actFrame in range(first_frame+1, end_frame+1):
    bpy.context.scene.frame_current = actFrame
    bpy.ops.node.sverchok_update_all()

    bpy.ops.object.join_shapes()
    bpy.context.object.active_shape_key_index = actFrame-1
    keys_name = bpy.context.object.data.shape_keys.name
    k = bpy.data.shape_keys[keys_name]
    k.key_blocks[-1].value = 1
    name = bpy.data.shape_keys[keys_name].key_blocks[-1].name
    bpy.data.shape_keys[keys_name].keyframe_insert(data_path='key_blocks["'+ name +'"].value')
    k.key_blocks[-2].value = 0
    name_p = bpy.data.shape_keys[keys_name].key_blocks[-2].name
    bpy.data.shape_keys[keys_name].keyframe_insert(data_path='key_blocks["'+ name_p +'"].value')
    bpy.context.scene.frame_current = actFrame-1
    k.key_blocks[-1].value = 0
    bpy.data.shape_keys[keys_name].keyframe_insert(data_path='key_blocks["'+ name +'"].value')

(It was asked here #469 but I opened a new issue to keep it cleaner)

Maybe it could became one sverchok operator but by now here is the script :)

[zeffii]

i want to add my support for this approach to animation via sverchok. Using sverchok as only part of the process allows you to control a lot more, even animate properties that don't have socket-input.

[nortikin]

why not modify this
https://github.com/nortikin/sverchok/blob/master/node_scripts/SNLite_templates/shape_key_bake.py
It can be as node to bake one object

[zeffii]

@vicdoval reckon you could assemble a small script that does, something like

for frame in range(30, 60):
    # set desired render file name and location ( if it can't be done automatically )
    # render()

[vicdoval]

Like this?
The bad thing is that it does not report to the ui the render progress.
It has been done in 2.79, when i try it in 2.8 does not save the file but i does not report any errors...

import bpy 
file_name = '/tmp\\imtest2\\'

start_frame = 10
end_frame =14

for act_frame in range(start_frame, end_frame + 1):
    bpy.context.scene.frame_current = act_frame
    bpy.ops.node.sverchok_update_all()
    bpy.ops.render.render()
    this_file = file_name + str(act_frame).zfill(4) +'.png'
    bpy.data.images["Render Result"].save_render(filepath=this_file)
    print(act_frame)

print ('done')

[zeffii]

hmmm.. i think maybe the solution is to add an event handler in the script (post_render) to do the save_render(file_path=.... ) stuff..

i suspect when you set the frame_current, that would already trigger sverchok_update_all()

[vicdoval]

I will try to check the handler idea

i suspect when you set the frame_current, that would already trigger sverchok_update_all()

I thought so too, but if you update the frame from a script it does not update the nodetree

[vicdoval]

the 2.8 version of the "baking animation to shapekeys" script:

import bpy

original_name = bpy.context.active_object.name
first_frame = bpy.context.scene.frame_start 
end_frame = bpy.context.scene.frame_end 
bpy.context.scene.frame_current = first_frame
bpy.ops.node.sverchok_update_all()
bpy.ops.object.duplicate()
bpy.context.active_object.name = 'Baked_' + original_name
bpy.context.active_object.data.name = 'Baked_' + original_name
bpy.data.objects[original_name].select_set(state=True)
bpy.ops.object.join_shapes()
for actFrame in range(first_frame+1, end_frame+1):
    bpy.context.scene.frame_current = actFrame
    bpy.ops.node.sverchok_update_all()

    bpy.ops.object.join_shapes()
    bpy.context.object.active_shape_key_index = actFrame-1
    keys_name = bpy.context.object.data.shape_keys.name
    k = bpy.data.shape_keys[keys_name]
    k.key_blocks[-1].value = 1
    name = bpy.data.shape_keys[keys_name].key_blocks[-1].name
    bpy.data.shape_keys[keys_name].keyframe_insert(data_path='key_blocks["'+ name +'"].value')
    k.key_blocks[-2].value = 0
    name_p = bpy.data.shape_keys[keys_name].key_blocks[-2].name
    bpy.data.shape_keys[keys_name].keyframe_insert(data_path='key_blocks["'+ name_p +'"].value')
    bpy.context.scene.frame_current = actFrame-1
    k.key_blocks[-1].value = 0
    bpy.data.shape_keys[keys_name].keyframe_insert(data_path='key_blocks["'+ name +'"].value')

[zeffii]

I thought so too, but if you update the frame from a script it does not update the nodetree

ok. hmmmm.

[vicdoval]

this would work rendering n frames in the 2.8

import bpy 
file_path = '/tmp\\imtest8\\'

start_frame = 10
end_frame =14

for act_frame in range(start_frame, end_frame + 1):
    bpy.context.scene.frame_current = act_frame
    bpy.ops.node.sverchok_update_all()
    bpy.context.scene.render.filepath = file_path + str(act_frame).zfill(4) +'.png'
    bpy.ops.render.render(write_still=True)
    print(act_frame)

print ('done')

[javismiles]

@vicdoval yes this works thank you ;)

[enzyme69]

@nortikin Your Script Node Lite solution is interesting but not sure how it would work? I tried it does not work.

I have weird method at some point, basically passing the data into Shapekeys... via Object ID.
https://www.youtube.com/watch?v=eIPRhKzJ6fM

It's like Victor baking data into shapekeys.

UPDATE: Ok wait maybe not above one, but I did "propose" or asking question about using Shapekeys as "Intermediate Object"....

This one:
https://www.youtube.com/watch?v=OBx1JmbIfrY

ANYWAYS... I think @vicdoval solution is simplest.

[nortikin]

@nortikin How to use this node? about (shape_key_bake.py)。I hope you can give me an example to understand it

update sverchok - collections links added
link nodes:

choose frame and define parameters:

change active to 1 and back to 0 to deactivate after:

[nortikin]

@nortikin use blender2.91.No bake shape keys,what should I do to bake shape keys

upgrade sverchok and add SNL shape key bake again from scratch