/*******************************************************************************
* Copyright (c) 2005 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.bpel.common.ui.flatui;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Control;
public final class FlatFormAttachment {
/**
* numerator specifies the numerator of the "a" term in the
* equation, y = ax + b, which defines the attachment.
*/
public int numerator;
/**
* denominator specifies the denominator of the "a" term in the
* equation, y = ax + b, which defines the attachment.
*
* The default value is 100.
*/
public int denominator = 100;
/**
* offset specifies the offset, in pixels, of the control side
* from the attachment position.
* If the offset is positive, then the control side is offset
* to the right of or below the attachment position. If it is
* negative, then the control side is offset to the left of or
* above the attachment position.
*
* This is equivalent to the "b" term in the equation y = ax + b.
* The default value is 0.
*/
public int offset;
/**
* control specifies the control to which the control side is
* attached.
*/
public Control control;
/**
* alignment specifies the alignment of the control side that is
* attached to a control.
* For top and bottom attachments, TOP, BOTTOM and CENTER are used. For left
* and right attachments, LEFT, RIGHT and CENTER are used. If any other case
* occurs, the default will be used instead.
*
* Possible values are:
*
* TOP: Attach the side to the top side of the specified control.
* BOTTOM : Attach the side to the bottom side of the specified control.
* LEFT: Attach the side to the left side of the specified control.
* RIGHT: Attach the side to the right side of the specified control.
* CENTER: Attach the side at a position which will center the control on
* the specified control.
* DEFAULT: Attach the side to the adjacent side of the specified control.
*/
public int alignment;
FlatFormAttachment () {
}
/**
* Constructs a new instance of this class given a numerator
* and denominator and an offset. The position of the side is
* given by the fraction of the form defined by the numerator
* and denominator.
*
* @param numerator the numerator of the position
* @param denominator the denominator of the position
* @param offset the offset of the side from the position
*/
public FlatFormAttachment (int numerator, int denominator, int offset) {
if (denominator == 0) SWT.error (SWT.ERROR_CANNOT_BE_ZERO);
this.numerator = numerator;
this.denominator = denominator;
this.offset = offset;
}
/**
* Constructs a new instance of this class given a numerator
* and an offset. Since no denominator is specified, the default
* is to read the numerator as a percentage of the form, with a
* denominator of 100.
*
* @param numerator the percentage of the position
* @param offset the offset of the side from the position
*/
public FlatFormAttachment (int numerator, int offset) {
this (numerator, 100, offset);
}
/**
* Constructs a new instance of this class given a control,
* an offset and an alignment.
*
* @param control the control the side is attached to
* @param offset the offset of the side from the control
* @param alignment the alignment of the side to the control it is attached to
*/
public FlatFormAttachment (Control control, int offset, int alignment) {
this.control = control;
this.offset = offset;
this.alignment = alignment;
}
/**
* Constructs a new instance of this class given a control
* and an offset. Since no alignment is specified, the default
* alignment is to attach the side to the adjacent side of the
* specified control.
*
* @param control the control the side is attached to
* @param offset the offset of the side from the control
*/
public FlatFormAttachment (Control control, int offset) {
this (control, offset, SWT.DEFAULT);
}
/**
* Constructs a new instance of this class given a control.
* Since no alignment is specified, the default alignment is
* to attach the side to the adjacent side of the specified
* control. Since no offset is specified, an offset of 0 is
* used.
*
* @param control the control the side is attached to
*/
public FlatFormAttachment (Control control) {
this (control, 0, SWT.DEFAULT);
}
FlatFormAttachment divide (int value) {
return new FlatFormAttachment (numerator, denominator * value, offset / value);
}
int gcd (int m, int n) {
int temp;
m = Math.abs (m); n = Math.abs (n);
if (m < n) {
temp = m;
m = n;
n = temp;
}
while (n != 0){
temp = m;
m = n;
n = temp % n;
}
return m;
}
FlatFormAttachment minus (FlatFormAttachment attachment) {
FlatFormAttachment solution = new FlatFormAttachment ();
solution.numerator = numerator * attachment.denominator - denominator * attachment.numerator;
solution.denominator = denominator * attachment.denominator;
int gcd = gcd (solution.denominator, solution.numerator);
solution.numerator = solution.numerator / gcd;
solution.denominator = solution.denominator / gcd;
solution.offset = offset - attachment.offset;
return solution;
}
FlatFormAttachment minus (int value) {
return new FlatFormAttachment (numerator, denominator, offset - value);
}
FlatFormAttachment plus (FlatFormAttachment attachment) {
FlatFormAttachment solution = new FlatFormAttachment ();
solution.numerator = numerator * attachment.denominator + denominator * attachment.numerator;
solution.denominator = denominator * attachment.denominator;
int gcd = gcd (solution.denominator, solution.numerator);
solution.numerator = solution.numerator / gcd;
solution.denominator = solution.denominator / gcd;
solution.offset = offset + attachment.offset;
return solution;
}
FlatFormAttachment plus (int value) {
return new FlatFormAttachment (numerator, denominator, offset + value);
}
int solveX (int value) {
if (denominator == 0) SWT.error (SWT.ERROR_CANNOT_BE_ZERO);
return ((numerator * value) / denominator) + offset;
}
int solveY (int value) {
if (numerator == 0) SWT.error (SWT.ERROR_CANNOT_BE_ZERO);
return (value - offset) * denominator / numerator;
}
@Override
public String toString () {
String string = control != null ? control.toString () : numerator + "/" + denominator; //$NON-NLS-1$
return "y = (" + string + (offset >= 0 ? ")x + " + offset: ")x - " + (-offset)); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
}
}