org.latdraw.beans
Class View

java.lang.Object
  org.latdraw.beans.View

public class View
extends java.lang.Object

This holds information about the current window (viewport) in lattice coordinates and the transformation to screen coordinates.

3D Lattice Coordinates: 3-space with the least element of the lattice (or ordered set) at the origin. (Ordered set without 0 can be drawn by adding a 0 and not displaying it.) The z coordinate of every element will be nonnegative.

Screen Transform: the lattice coordinates will be projected to a plane containing the z axis. (This is not done here but in Diagram.) The origin will be mapped to a screen point centered horizontally and 5% above the bottom edge.

This could handle zooming if we want it. old: This holds the current window (viewport) in lattice coordinates being displayed. Suppose you want to display the nose. If the length of the board is 180, you might want to show from x = 160 to x = 190 and vertically you want the board centered. To do this you would construct a View by

new View(View.HORIZONTAL, new double[] {160, 190}, 0.0)

So a View has a direction either HORIZONTAL or VERTICAL, a range, and a value of the center in the other direction. There is also a boolean to indicate whether the vertical coordinate goes up or down. There is also a verticalShiftFrac which will shift the the image vertically in screen by the screen (window) height times this. In the HORIZONTAL case, with a range [x_0, x_1] of x values and a single y value, the view the user will see will be a rectangle with upper left [x_0, y - d] and lower right [x_1, y + d] where d is as big as can be shown on the screen given that the aspect ratio must be preserved.

This class is bacically immutable except for the transforms.

Version:

$Id: View.java,v 1.4 2003/08/25 09:12:07 ralph Exp $

Author:

Ralph Freese

Constructor Summary

View()

Method Summary

java.awt.geom.AffineTransform	getLatToScreen()
java.awt.geom.AffineTransform	getLatToScreen(double wd, double ht)
java.awt.geom.AffineTransform	getScreenToLat()
java.awt.geom.AffineTransform	getScreenToLat(double wd, double ht)
void	setTransform(double w, double h) Set the latToScreen transfrom for the view port to be shown.

Methods inherited from class java.lang.Object

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

Constructor Detail

View

public View()

Method Detail

setTransform

public void setTransform(double w,
                         double h)

Set the latToScreen transfrom for the view port to be shown.

getLatToScreen

public java.awt.geom.AffineTransform getLatToScreen()

getLatToScreen

public java.awt.geom.AffineTransform getLatToScreen(double wd,
                                                    double ht)

getScreenToLat

public java.awt.geom.AffineTransform getScreenToLat()

getScreenToLat

public java.awt.geom.AffineTransform getScreenToLat(double wd,
                                                    double ht)