setup_skin_animation.py

# Skin animation setup script
# Written by DiFFtY (diffty@gmail.com), inspired by Miek's cloaking script (https://github.com/miek/sfm_scripts/tree/master/setup_cloaking)
# This script allows you to create a new channel in an Animation Set to control the skin number of a game model.
#
# Usage : Right click on a model Animation Set, go to Rig -> Load Rig Script, then open this .py
#
# Tested on SFM 0.9.7.6, 10/05/2013

import vs

def SetupSkin():
    # Get the currently selected animation set and shot, and the corresponding gamemodel
    shot = sfm.GetCurrentShot()
    animSet = sfm.GetCurrentAnimationSet()
    gameModel = animSet.gameModel

    # Creating the control group
    controlGroup = animSet.FindOrAddControlGroup(animSet.GetRootControlGroup(), "Skin")

    # Creating the control in the animation set
    skinControl, skinValue = sfmUtils.CreateControlledValue("skin", "value", vs.AT_FLOAT, 0.0, animSet, shot)
    controlGroup.AddControl(skinControl)

    # Creating an operator/expression, to adapt the 0.0 -> 1.0 float information provided by the slider to a 0 -> number of skins in the gamemodel
    expression = sfmUtils.CreateExpression("skin_rescale", "floor(lerp(value, lo, hi))", animSet)
    expression.AddAttribute("lo", vs.AT_FLOAT)
    expression.AddAttribute("hi", vs.AT_FLOAT)
    expression.SetValue("hi", gameModel.GetSkinCount()-1)
    expression.AddAttribute("value", vs.AT_FLOAT)

    # Connecting the normalized slider user-provided info to the expression
    skinControl.channel.SetOutput(expression, "value")

    # Creating the second channel, which take the result of the expression and assign it to the gamemodel skin info
    rescaleChannel = sfmUtils.CreateChannel("rescaled_skin_channel", vs.AT_FLOAT, 0., animSet, shot)
    rescaleChannel.SetInput(expression, "result")
    rescaleChannel.SetOutput(gameModel, "skin")

    # Removing keyframes from the second channel
    # (to avoid the default blank key (added in the CreateChannel() function) to override ones from the first channel, which are the ones set by the user)
    for i in range(0, rescaleChannel.log.GetKeyCount()):
        rescaleChannel.log.RemoveKey(0)

    return

#==================================================================================================
# Script entry
#==================================================================================================

# Setup skin channel for the selected animation set
SetupSkin()