Class ViewGraph

java.lang.Object
  ViewGraph

public class ViewGraph
extends java.lang.Object

This is and interactive graphical program for viewing and editing a graph.

Usage : java ViewGraph < input.graph

where

• input.graph is a file containing a graph specified as an adjacency list. More specifically, each vertex is represented by a unique string. For each line of input the vertex represented by the first string on the line is connected to the vertices represented by any following strings.

A complete description of the mouse and button controls for the program is given at this link.

As an example, the following two listings specifiy the graph shown in the picture below.

A B
C D
C E
B E
D F
F G
A G
G H
G C
B C
I

C B D E
B A E
F D G
G A H C
I

ViewGraph mouse, button and key instructions

ViewGraph is controled by a slide bar, some buttons, the arrow, home and shift keys, but mostly by mouse operations.

All three mouse buttons are used. For mice with 1 or 2 buttons, left mouse with the control key held down should have the same effect as middle mouse, and left mouse with the meta key held down should have the same effect as right mouse. (Warning for my PC the control key fix works but the meta key one doesn't. I'm not even sure which the meta key is. However, the right mouse button of the two on the PC works like the right one of three.)

• The slide bar on the right hand side controls the repulsive force in the energy equation used to set the coordinates. Slide up to reduce repulsion and down to increase it.



• At the bottom of the frame there are 5 controls. From left to right they are as follows.
  
  • The page control pull down menu controls the appearance, orientation and size of a page of paper. The top left hand corner of the page is always at the origin. This is useful to preview how a print out will look.
  
  
  • The print button calls up the system's print frame. The hard copy produced should look the same as what shows on the paper chosen by the pull down menu above.
  
  
  • The run/stop button starts and stops the thread that optimised the positions of the vertices. You should stop the thread if you need to print.
  
  
  • The view/edit button changes the effect of mouse operations in the main canvas. See below for what they do.
  
  
  • The text input space on the right hand side allows you to type in the name of a vertex. When you then press return the vertex moves to the origin. If the vertex has previously been deleted it is put back into the graph.
  
  


• Mouse operations in view mode with no shift key pressed .
  • Left mouse. Drags a vertex. Vertex is free on release.
  • Middle mouse. Drags a vertex. Vertex is fixed at release position.
  • Right mouse. Translates the view by the amount dragged. A bit like putting your finger on a piece of paper and moving it.
  
  
  
  • Double click with any mouse button in the background resets the vertices to their initial positions.


• Mouse operations in view mode with shift key pressed .
  • Left mouse. Drags a vertex and the component it is in. Vertex and component free on release.
  • Middle mouse. Drags a vertex and the component it is in. Vertex and component are fixed at release positions.
  • Right mouse. Translates the positions of the vertices relative to the position of the paper by the amount dragged. This is useful to center the picture on the paper ready for outputing.
  
  
  
  • Double click with any mouse button in the background same as view mode without shift.


• Mouse operations in edit mode with no shift key pressed .
  • Left mouse. Click on a vertex to add its neighbours to the graph.
  • Middle mouse. Click on a vertex to delete it from the graph.
  • Right mouse. Same as view mode without shift.
  
  
  
  • Double click left mouse replaces all deleted vertices in the graph.
  • Double click middle mouse deletes all vertices from the graph.
  • Double click right mouse has no effect.


• Mouse operations in edit mode with shift key pressed .
  • Left mouse. Click on a vertex to replace all vertices in the same component to the graph.
  • Middle mouse. Click on a vertex to delete it and the component it is in from the graph.
  • Right mouse. Does nothing.
  
  
  
  • Double click left mouse is the same as edit mode without shift key.
  • Double click middle mouse is the same as edit mode without shift key.
  • Double click right mouse is the same as edit mode without shift key.


• Arrow key functions with no shift key pressed . Mouse has to be in the picture canvas.
  • Up arrow. Increases the scale of viewing by 10%.
  • Down arrow. Decreased the scale of viewing by 10%.
  • Left arrow. Rotates the view by 15 degrees clockwise.
  • Right arrow. Rotates the view by 15 degrees anticlockwise.


• Arrow key functions with shift key pressed . Mouse has to be in the picture canvas.
  • Up arrow. Increases the vertex positions by 10% relative to the scale of the paper.
  • Down arrow. Decreases the vertex positions by 10% relative to the scale of the paper.
  • Left arrow. Rotates the vertex positions by 15 degrees clockwise relative to the paper orientation.
  • Right arrow. Rotates the vertex poritions by 15 degrees anticlockwise relative to the paper orientation.


• Pressing the home key undoes all transformations and replaces the origin at the top left of the screen.

Constructor Summary

ViewGraph()

Method Summary

static void

main(java.lang.String[] args)

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ViewGraph

public ViewGraph()

Method Detail

main

public static void main(java.lang.String[] args)