Expression Control

Introduction

There is an Expression Control Mode in the decision node, which allows us that use expressions or scripts to directly control the output result of a sentence.

Video Tutorial

Advanced Tutorials Variable & Expression part

Instructions

Switch the mode of decision node from normal to the “expression” mode.

Please notice in this mode, only 1 input and 1 output channel available.

_{expression mode of decision node}

_{only 1 input and 1 output available}

Sentences Tim

Input condition:

You can choose any one sentence from GUI, and then delete the arithmetic part of sentence ( < ??) or ( from ?? to ?? ) or ( < ?? ) or (LEFT/RIGHT/UP/DOWN) etc...

For example:

• spot to me distance < ??
• spot to me distance

• my type ID from ?? to ??
• my type ID

Output decision

you can choose any one sentence from GUI, and then delete the value content part of sentence ( ?? )

For example:

• move FORWARD as speed ??
• move FORWARD as speed

• set maya attribute:??? value ??
• set maya attribute:??? value

Example 1

Using sentence return value to control Head Translate Offset

_{(Noise ID) rand float based on my id}

_{(Bone Offset) set my bone:head translate Y offset}

_{head offset directly controlled by expression}

Example 2

Using sentence return value to control expression and then control the Head Translate Offset

_{(Agent ID) my ID}

_{giving agent id value to attribute "aaa"}

_{use my ID -> aaa -> expression -> control the head bone Y offset}

_{head offset Y controlled by value of agent ID}

Please notice that, do not contain "blanks" in python code session:

maya python:${aaa}+0.1 (correct)

maya python:${aaa} + 0.1 (incorrect)

Additionally, you can use real python command to control this:

maya python:abc(${aaa})

define a python command:

def abc(var):

  return var * 5