/* -*- tab-width: 4 -*-
*
* Electric(tm) VLSI Design System
*
* File: RegionGoal.java
* Written by: Christian Harnisch, Ingo Besenfelder, Michael Neumann (Team 3)
*
* Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
*
* Electric(tm) 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.
*
* Electric(tm) 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 Electric(tm); see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, Mass 02111-1307, USA.
*/
package com.sun.electric.tool.routing.experimentalAStar2.goal;
import com.sun.electric.tool.routing.experimentalAStar2.algorithm.AStarGoalBase;
import com.sun.electric.tool.routing.experimentalAStar2.algorithm.AStarOpenListBase;
import com.sun.electric.tool.routing.experimentalAStar2.algorithm.AStarRegionNode;
public class RegionGoal implements AStarGoalBase<AStarRegionNode>
{
/* Tuning parameters */
/**
* Parameter to set penalty for bends in wires. 1 is enough. Set 0 to disable.
*/
private static final int BEND_PENALTY = 5;
/**
* Parameter to set penalty for using vias in paths.
*/
private static final int VIA_PENALTY = 5;
/*
* From here on below: Private variables for internal use. Don't try to tune
* these.
*/
private AStarOpenListBase<AStarRegionNode> openList;
private AStarRegionNode goalNode;
private int maxRevolutions = 0;
private int distance(int startX, int startY, int startZ, int endX, int endY, int endZ)
{
return 10 * (Math.abs(startX - endX) + Math.abs(startY - endY) + (Math.abs(startZ - endZ)));
}
/*
* (non-Javadoc)
*
* @see
* com.sun.electric.tool.routing.astar.t3.algorithm.AStarGoalBase#distanceToGoal
* (int, int, int)
*/
public int distanceToGoal(int startX, int startY, int startZ)
{
int viaPenaltyEstimation = Math.abs(startZ - this.goalNode.getZ()) * VIA_PENALTY;
return distance(startX, startY, startZ, this.goalNode.getX(), this.goalNode.getY(), this.goalNode.getZ())
+ viaPenaltyEstimation;
}
/*
* (non-Javadoc)
*
* @see
* com.sun.electric.tool.routing.astar.t3.algorithm.AStarGoalBase#getNodeCost
* (com.sun.electric.tool.routing.astar.t3.algorithm.AStarNode, int, int, int)
*/
public int getNodeCost(AStarRegionNode from, int toX, int toY, int toZ)
{
/*
* If we go horizontally on one layer, we prevent vertical wires from being
* routed. Thus, the cost of moving between two horizontally adjacent nodes
* is the capacity we destroy that way. This is also true the other way
* round (moving vertically prevents horizontal wires from being routed).
*
* Obviously, the more accurate the capacity calculating algorithm can
* determine the capacities, the better A* behaves.
*/
int bendPenalty = 0;
int viaPenalty = 0;
if (from.getZ() != toZ)
viaPenalty = VIA_PENALTY;
// Moving horizontally
if (from.getY() == toY)
{
// Bends are bad, even globally
if (from.origin != null)
if (from.origin.getY() != toY)
bendPenalty = BEND_PENALTY;
return (distance(from.getX(), from.getY(), from.getZ(), toX, toY, toZ) + from.getVerticalCapacity() + bendPenalty + viaPenalty);
}
else
// Moving vertically
if (from.getX() == toX)
{
// Bends are bad, even globally
if (from.origin != null)
if (from.origin.getX() != toX)
bendPenalty = BEND_PENALTY;
return (distance(from.getX(), from.getY(), from.getZ(), toX, toY, toZ) + from.getHorizontalCapacity() + bendPenalty + viaPenalty);
}
else
{
/*
* Moving diagonally: Does not make sense for global routing. How do you
* intend to route diagonally between two regions, without touching the
* other adjacent regions?
*/
throw new IllegalArgumentException("Routing diagonally is not allowed globally, tried to route from (" + from.getX() + ","
+ from.getY() + "," + from.getZ() + ") to (" + toX + "," + toY + "," + toZ + ").");
}
}
/*
* (non-Javadoc)
*
* @see
* com.sun.electric.tool.routing.astar.t3.algorithm.AStarGoalBase#isPathFinished
* (com.sun.electric.tool.routing.astar.t3.algorithm.AStarNode)
*/
public boolean isPathFinished(AStarRegionNode currentNode)
{
// Arrived at goal node
return this.goalNode.equals(currentNode);
}
/*
* (non-Javadoc)
*
* @see
* com.sun.electric.tool.routing.astar.t3.algorithm.AStarGoalBase#setGoalNode
* (com.sun.electric.tool.routing.astar.t3.algorithm.AStarNode)
*/
public void setGoalNode(AStarRegionNode goal)
{
this.goalNode = goal;
}
/*
* (non-Javadoc)
*
* @seecom.sun.electric.tool.routing.astar.t3.algorithm.AStarGoalBase#
* setMaximumRevolutions(int)
*/
public void setMaximumRevolutions(int maximum)
{
this.maxRevolutions = maximum;
}
/*
* (non-Javadoc)
*
* @see
* com.sun.electric.tool.routing.astar.t3.algorithm.AStarGoalBase#setNodeStorage
* (com.sun.electric.tool.routing.astar.t3.algorithm.AStarOpenListBase)
*/
public void setNodeStorage(AStarOpenListBase<AStarRegionNode> openList)
{
this.openList = openList;
}
/*
* (non-Javadoc)
*
* @see
* com.sun.electric.tool.routing.astar.t3.algorithm.AStarGoalBase#shouldGiveUp
* (int)
*/
public boolean shouldGiveUp(int currentRevolutions)
{
// Maximum search time exceeded
if (maxRevolutions > 0 && currentRevolutions >= maxRevolutions)
return true;
// No more nodes to search, thus, no possible path exists.
if (openList.isOpenListEmpty())
return true;
return false;
}
}