How to make an Object Clickable

Given that you have an object in your scene (e.g. a book), this tutorial explains how to make it "clickable" - when you click on the object, it will trigger an action or a Python script.

Preparing the object

Create and configure a click region

You will first need to create a "click region" around your object. Below are the steps to create a click region:

  1. Choose Scripts->Add->PyPRP, then choose "Add a (Generic) Logic Region". It will appear in layer 2.
  2. Select it, then move it to the place where the avatar will be standing when they attempt to click on the object. Below is an example of a click region surrounding a book.
    Clickregion.jpg
  3. Scale it so that it can encompass an avatar and the object that is clickable, then hit Ctrl-A to apply scale and rotation into the vertices.
  4. Rename the object to something meaningful (e.g. MyClickRegion)
  5. On the Logic panel:
    1. Click on Bounds, then set it to "Convex Hull Polytope"
    2. Click the Actor button on the Logic panel
    3. Your Logic panel should look like this:

Clickregionprops.jpg

Configure the clickable

Next, you need to prepare your object to be "clickable":

  1. Select the object
  2. On the Logic panel:
    1. Click on Bounds, then set it to "Convex Hull Polytope"
    2. Click the Actor button on the Logic panel
  3. Add the following AlcScript entry:
ObjectName:
    physical:
        pinned: true

But change "ObjectName" to your object's name. Now your object is ready to become a clickable.


The simpleclick quickscript

To make the object clickable we have to add more AlcScript. This article will discuss the easy way: the simpleclick quickscript. The simpleclick script was originally designed to call a Python file but currently it can also trigger a sound or an avatar animation.

First we will look at the Python file option:

ObjectName:
    physical:
        pinned: true
    quickscript:
        simpleclick:
            pythonfile: myPythonFile
            region: MyClickRegion

Change "ObjectName" to your object's name, "myPythonFile" to the name of your python file, and "MyClickRegion" to the name of your click region.

Now you're ready to write your Python script. If you wish to write a linking book or journal, please use D'Lanor's Dynamic Book Template.


If the clickable object is not a book you can use the following basic Python code.

actClickableObject = ptAttribActivator(1, 'Clickable object activator')
strObject = ptAttribString(2, 'Object string')

class myPythonFile(ptModifier,):

    def OnNotify(self, state, id, events):
        if ((id == actClickableObject.id) and state):
            print ('Object %s was clicked' % strObject.value)
            #place your code here

Note: this Python code needs to go into an external Python file. For instructions on creating a Python file, click here.

Adding an avatar animation

ObjectName:
    physical:
        pinned: true
    quickscript:
        simpleclick:
            pythonfile: myPythonFile
            region: MyClickRegion
            animation: <animation name>
            animtarget: <animation start>

Change <animation name> to the name of an animation without the Male/Female prefix. Change <animation start> to the name of an object placed at the position where you want the animation to start.

The animation will not run automatically this way. We need a bit of Python script to activate it (for running avatar animations without Python see further below).

actClickableObject = ptAttribActivator(1, 'Clickable object activator')
strObject = ptAttribString(2, 'Object string')
Behavior = ptAttribBehavior(3, 'Avatar animation')
kAnimSeconds = 2.0
kAnimID = 1

class myPythonFile(ptModifier,):

    def OnNotify(self, state, id, events):
        if ((id == actClickableObject.id) and state):
            Avatar = PtFindAvatar(events)
            Behavior.run(Avatar)
            #this timer allows the avatar animation to finish
            PtAtTimeCallback(self.key, kAnimSeconds, kAnimID)



    def OnTimer(self, id):
        if (id == kAnimID):
            #here comes the action for your clickable



# paste default glue section here


Adding a click sound

ObjectName:
    physical:
        pinned: true
    quickscript:
        simpleclick:
            pythonfile: myPythonFile
            region: MyClickRegion
            soundemitter: MyEmitter

Change "MyEmitter" to the name of your sound emitter.


PyPRP 1.4.0 updates

The simpleclick quickscript has been updated to add more flexibility.

Don't worry about your existing simpleclick quickscripts. They should still produce the same results as they did before this update.

Clickables without Python

It is no longer necessary to use a Python file if you only want to trigger a sound and/or avatar animation. In this case you can simply leave out the pythonfile line.

Avatar animation autorun

Even if you are using a Python file the avatar animation can now run without being triggered by Python. To control this we have a new optional flag called autorun. The values for autorun are true or false. The following example creates an automatic avatar animation.

ObjectName:
    physical:
        pinned: true
    quickscript:
        simpleclick:
            pythonfile: myPythonFile
            region: MyClickRegion
            animation: <animation name>
            animtarget: <animation start>
            autorun: true

Not using a Python file always results in an automatic avatar animation. This ignores the autorun setting (the false value would make no sense here).

If pythonfile is specified autorun defaults to false, assuming you will trigger the animation in your Python file (this matches the old behavior). This default behavior can be altered by adding autorun: true as shown in the exampe above.


Facing condition

The facing condition makes it possible to show the hotspot of a clickable object only if the avatar is facing its negative Y-axis.

Note: You must use PyPRP 1.4.0 or higher for this.

  1. Make sure to set the Transform Orientation (Alt Space) to Local (yellow circle)
  2. Rotate the clickable until the green arrow of the Y-axis points in the opposite direction you want the avatar to face (yellow arrow)
  3. You may find that the axis is now correct but the object has a wrong orientation. In that case you can apply the rotation (Ctrl A) and try again. If you play a bit with apply and rotate you will eventually get it right.


Facing condition.png


Now add the "facevalue" property to your Alcscript. This sets the facing tolerance.

ObjectName:
    physical:
        pinned: true
    quickscript:
        simpleclick:
            pythonfile: myPythonFile
            region: MyClickRegion
            facevalue: 0.9

Working tolerance values are between 0 and 1 (not exactly 0 or 1). Low values are for high tolerance angles. A value close to zero means that the angle is close to 180 degrees, but it will still prevent the avatar from hitting the clickable while facing away.
The higher the value, the lower the angle. 0.9 seems a useful general purpose value that gives the avatar just enough slack.