Terrain Decals

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Client Scripting

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Reference

Client Scripting API  •  Client Commands

Contents 1 Overview 2 Key binding 3 Compass scripts 3.1 The ShowCompass method 3.2 The HideCompass method 3.3 The MoveHandler event handler method 3.4 The ToggleCompass method

Overview

The Multiverse Client can display decals, images on the ground attached to static objects, mobs, or players. The primary mechanism for displaying decals is the Decal class in the Client scripting API.

The Sampleworld player compass decal is a good example of a decal attached to a player. In Sampleworld, you can toggle display of this decal with Ctrl-C.

Key binding

The Bindings.xml file defines the command to toggle display of the compass with this code:

<Binding name="COMPASS" header="ACTIONS">
     PlayerCompass.ToggleCompass()
</Binding>

The bindings.txt file specifies the key sequence that triggers this command as follows:

CTRL-C COMPASS

Compass scripts

The code for the Sampleworld player compass is in Scripts/PlayerCompass.py. This file contains the following methods:

• ShowCompass() - to create and display the compass decal
• HideCompass() - to turn off display of the compass decal
• MoveHandler() - event handler to display the decal and move it when the player avatar moves
• ToggleCompass() - method called by the Ctrl-C key binding, to alternately call ShowCompass() and HideCompass().

The ShowCompass method

The ShowCompass() method creates and displays the decal. In the following lines of code, it gets the player object form the ClientAPI.GetPlayerObject method, then registers the MoveHandler event handler. Then the Decal constructor creates the compass decal at the player's position:

def ShowCompass():
   global CompassDecal
   global CompassOn
   player = ClientAPI.GetPlayerObject()
   player.SceneNode.RegisterEventHandler('Updated', MoveHandler)
   CompassDecal = ClientAPI.Decal.Decal("compass-rose.png", player.Position.x, player.Position.z, 2000, 2000, 5)
   CompassOn = True

The HideCompass method

The HideCompass method does basically the oppositoe of ShowCompass; it stops displaying the compass decal.

def HideCompass():
   global CompassDecal
   global CompassOn
   player = ClientAPI.GetPlayerObject()
   player.SceneNode.RemoveEventHandler('Updated', MoveHandler)
   CompassDecal.Dispose()
   CompassDecal = None
   CompassOn = False

The MoveHandler event handler method

The ShowCompass method registers this method as the event handler to call whenever the player's position is updated, and the method then repositions the decal to the player's new position:

def MoveHandler(pos, orient, scale):
   global CompassDecal
   global CompassOn
   
   global LastX
   global LastZ
   if CompassOn:
       x = pos.x
       z = pos.z
       if LastX != x or LastZ != z:
           #ClientAPI.Write('updating compass: ' + str(x) + ', ' + str(z))
           CompassDecal.PosX = x
           CompassDecal.PosZ = z
           LastX = x
           LastZ = z

The ToggleCompass method

The ToggleCompass method is called when the player hits Ctrl-C. It alternately shows and hides the compass decal by calling ShowCompass and HideCompass.

def ToggleCompass():
   global CompassOn
   if CompassOn :
       HideCompass()
   else:
       ShowCompass()