Fun with z-fighting :3

smile!.py

from direct.showbase.ShowBase import ShowBase
from panda3d.core import *
from direct.task import Task


class MyApp(ShowBase):
    def __init__(self):
        ShowBase.__init__(self)
        
        self.velocity = .1
        
        self.unitMovementVector = Vec3(0, 0, 0)

        self.disableMouse()
        
        self.face = self.loader.loadModel("models/smiley");
        self.face.reparentTo(self.render)
        self.face.setScale(2, 2, 2)
        self.face.setPos(0, 0, 0)
        
        self.frown = self.loader.loadModel("models/frowney")
        self.frown.reparentTo(self.render)
        self.frown.setScale(2, 2, 2)
        self.face.setPos(0, .1, 0)

        self.camera.setPos(0, -20, 0)
        self.camera.lookAt(self.face)

        self.accept("arrow_left",   self.arrowDown, ["left"]    )
        self.accept("arrow_right",  self.arrowDown, ["right"]   )
        self.accept("arrow_down",   self.arrowDown, ["down"]    )
        self.accept("arrow_up",     self.arrowDown, ["up"]      )
        
        self.accept("arrow_left-up",     self.arrowUp,   ["left"]       )
        self.accept("arrow_right-up",    self.arrowUp,   ["right"]      )
        self.accept("arrow_up-up",       self.arrowUp,   ["up"]         )
        self.accept("arrow_down-up",    self.arrowUp,    ["down"]       )
        
        self.taskMgr.add(self.onEnterFrame, "onEnterFrame")

    def arrowDown(self, arrow):
        if arrow == "left":
            self.unitMovementVector.x = -1
        if arrow == "right":
            self.unitMovementVector.x = 1
        if arrow == "down":
            self.unitMovementVector.y = 1
        if arrow == "up":
            self.unitMovementVector.y = -1
    
    def arrowUp(self, arrow):
        if arrow == "left" or arrow == "right":
            self.unitMovementVector.x = 0
        if arrow == "up" or arrow == "down":
            self.unitMovementVector.y = 0

    def onEnterFrame(self, task):
        currPos = self.face.getPos()
        currPos += self.unitMovementVector * self.velocity;
        self.face.setPos(currPos)
        return Task.cont


app = MyApp()
app.run()