//***************************************************************
// Copyright 2008 Centre For Advanced Spatial Analysis, UCL
//
// Author: Joel Dearden, University College London
//
// Contact: j.dearden@ucl.ac.uk
//
// Joel Dearden, 
// Centre for Advanced Spatial Analysis,
// University College London,
// 1-19 Torrington Place,
// London,
// WC1E 7HB
//
//
// This file is part of SLSegregationModel.
//
//  SLSegregationModel is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  SLSegregationModel is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with SLSegregationModel.  If not, see <http://www.gnu.org/licenses/>.
//
//***************************************************************


integer talkToLineSegments = -88821;

integer positioned = FALSE;

vector lineColour = <0,0,1>;

fitLine(vector previousPosition)
{
    
    llOwnerSay("fitline");
    
    vector currentPosition = llGetPos();
    
    //Put the matchstick centre at the midpoint of the line connecting the previous and current positions.
    
    vector midpoint = (currentPosition + previousPosition) / 2;
    
    llOwnerSay("midpoint=" + (string)midpoint);
    
    llSetPos(midpoint);
    
    //Rotate it so that the local z-axis matches the vector from the previous to the current position
    
    llLookAt(currentPosition, 1, 0);
    llStopLookAt();
    
    //Set the z-scale to match the distance from the previous to the current position.
    float requiredLength = llVecDist(previousPosition, currentPosition);
    
    vector newScale = llGetScale();    
    newScale.z = requiredLength;    
    llSetScale(newScale);    
    
    llOwnerSay("newScale=" + (string)newScale);
    
    //set correct colour and glow
    llSetColor(lineColour, ALL_SIDES);
    llSetPrimitiveParams([PRIM_GLOW, ALL_SIDES, 1.0]);
    
}

default
{
    state_entry()
    {
        
        //listen for clear messages
        llListen(talkToLineSegments, "", NULL_KEY, "");
    }
    
    listen(integer channel, string name, key id, string message)
    {
        
        llOwnerSay("got message:" + message);
        
        if(channel == talkToLineSegments)
        {
        
            if(positioned == FALSE)
            {
                if(lineColour == <1,0,0>)
                {
                    //red
                    if(llGetSubString(message, 0, 3) == "prp:")
                    {
                        
                        //previous position message
                        vector previousPosition = (vector) llGetSubString(message, 4, -1);
                                            
                        positioned = TRUE;
                        
                        fitLine(previousPosition);
                    }   
                }
                else
                {
                    
                    //blue
                    if(llGetSubString(message, 0, 3) == "pbp:")
                    {
                        
                        //previous position message
                        vector previousPosition = (vector) llGetSubString(message, 4, -1);
                                            
                        positioned = TRUE;
                        
                        fitLine(previousPosition);
                    }   
                }
            }
        
            if(message == "die")
            {
            
                llDie();    
            }    
        }   
    }
}