Post translate python

[brainspoon]

Is there a way to calculate the distance of an object to the rendering camera within a post translate python script?

I want to calculate the distance to an object and save that value into a metadata field of the rendered exr file.
Then I can use that value to automagically set the focus distance of the post dof in Nuke.

Thanks
Andreas

[vlado]

If you know the name of the exported Node plugin in the V-Ray scene, you can take its transformation matrix and from there you can take the position of the object. You can do the same for the "Render View" plugin, from where you can figure out the distance between the two.

Best regards,
Vlado

[brainspoon]

Actually I am nearly done. The only thing left is getting the position of my object that has to get into v2.

import maya.cmds as cmds
import pymel.core as pm
from vray.utils import *

distances=[]

pc = pm.xform( 'camname', q=True, translation=True, ws=True)
v1 = pm.datatypes.Vector(pc[0],pc[1],pc[2])
v2 = pm.datatypes.Vector(0,0,0)
distances.append( v1.distanceTo(v2))

l=findByName("vraySettingsEXR")
zNode=findByType('RenderChannelZDepth')
zFactor = zNode[0].get('depth_black')

l[0].set('extra_attributes',("targetDistance=%s; zfactor=%s" % (max(distances),zFactor)) )

[ivaylo.ivanov]

If you are using the nightlies, you can directly call a python or mel function to calculate the attribute. For distance, you even have Maya node. Here is a scene:

distance_test.zip

pSphere1 has temp and temp2 attributes that calculates the distance in two different ways.

[brainspoon]

Cool thanks. Will have a look into that.