| /******************************************************************************* |
| * Copyright (c) 2000, 2008 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.swt.graphics; |
| |
| |
| import org.eclipse.swt.internal.win32.*; |
| |
| /** |
| * Instances of this class provide measurement information |
| * about fonts including ascent, descent, height, leading |
| * space between rows, and average character width. |
| * <code>FontMetrics</code> are obtained from <code>GC</code>s |
| * using the <code>getFontMetrics()</code> method. |
| * |
| * @see GC#getFontMetrics |
| * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a> |
| */ |
| |
| public final class FontMetrics { |
| |
| /** |
| * On Windows, handle is a Win32 TEXTMETRIC struct |
| * On Photon, handle is a Photon FontQueryInfo struct |
| * (Warning: This field is platform dependent) |
| * <p> |
| * <b>IMPORTANT:</b> This field is <em>not</em> part of the SWT |
| * public API. It is marked public only so that it can be shared |
| * within the packages provided by SWT. It is not available on all |
| * platforms and should never be accessed from application code. |
| * </p> |
| */ |
| public TEXTMETRIC handle; |
| |
| /** |
| * Prevents instances from being created outside the package. |
| */ |
| FontMetrics() { |
| } |
| |
| /** |
| * Compares the argument to the receiver, and returns true |
| * if they represent the <em>same</em> object using a class |
| * specific comparison. |
| * |
| * @param object the object to compare with this object |
| * @return <code>true</code> if the object is the same as this object and <code>false</code> otherwise |
| * |
| * @see #hashCode |
| */ |
| public boolean equals (Object object) { |
| if (object == this) return true; |
| if (!(object instanceof FontMetrics)) return false; |
| TEXTMETRIC metric = ((FontMetrics)object).handle; |
| return handle.tmHeight == metric.tmHeight && |
| handle.tmAscent == metric.tmAscent && |
| handle.tmDescent == metric.tmDescent && |
| handle.tmInternalLeading == metric.tmInternalLeading && |
| handle.tmExternalLeading == metric.tmExternalLeading && |
| handle.tmAveCharWidth == metric.tmAveCharWidth && |
| handle.tmMaxCharWidth == metric.tmMaxCharWidth && |
| handle.tmWeight == metric.tmWeight && |
| handle.tmOverhang == metric.tmOverhang && |
| handle.tmDigitizedAspectX == metric.tmDigitizedAspectX && |
| handle.tmDigitizedAspectY == metric.tmDigitizedAspectY && |
| // handle.tmFirstChar == metric.tmFirstChar && |
| // handle.tmLastChar == metric.tmLastChar && |
| // handle.tmDefaultChar == metric.tmDefaultChar && |
| // handle.tmBreakChar == metric.tmBreakChar && |
| handle.tmItalic == metric.tmItalic && |
| handle.tmUnderlined == metric.tmUnderlined && |
| handle.tmStruckOut == metric.tmStruckOut && |
| handle.tmPitchAndFamily == metric.tmPitchAndFamily && |
| handle.tmCharSet == metric.tmCharSet; |
| } |
| |
| /** |
| * Returns the ascent of the font described by the receiver. A |
| * font's <em>ascent</em> is the distance from the baseline to the |
| * top of actual characters, not including any of the leading area, |
| * measured in pixels. |
| * |
| * @return the ascent of the font |
| */ |
| public int getAscent() { |
| return handle.tmAscent - handle.tmInternalLeading; |
| } |
| |
| /** |
| * Returns the average character width, measured in pixels, |
| * of the font described by the receiver. |
| * |
| * @return the average character width of the font |
| */ |
| public int getAverageCharWidth() { |
| return handle.tmAveCharWidth; |
| } |
| |
| /** |
| * Returns the descent of the font described by the receiver. A |
| * font's <em>descent</em> is the distance from the baseline to the |
| * bottom of actual characters, not including any of the leading area, |
| * measured in pixels. |
| * |
| * @return the descent of the font |
| */ |
| public int getDescent() { |
| return handle.tmDescent; |
| } |
| |
| /** |
| * Returns the height of the font described by the receiver, |
| * measured in pixels. A font's <em>height</em> is the sum of |
| * its ascent, descent and leading area. |
| * |
| * @return the height of the font |
| * |
| * @see #getAscent |
| * @see #getDescent |
| * @see #getLeading |
| */ |
| public int getHeight() { |
| return handle.tmHeight; |
| } |
| |
| /** |
| * Returns the leading area of the font described by the |
| * receiver. A font's <em>leading area</em> is the space |
| * above its ascent which may include accents or other marks. |
| * |
| * @return the leading space of the font |
| */ |
| public int getLeading() { |
| return handle.tmInternalLeading; |
| } |
| |
| /** |
| * Returns an integer hash code for the receiver. Any two |
| * objects that return <code>true</code> when passed to |
| * <code>equals</code> must return the same value for this |
| * method. |
| * |
| * @return the receiver's hash |
| * |
| * @see #equals |
| */ |
| public int hashCode() { |
| return handle.tmHeight ^ handle.tmAscent ^ handle.tmDescent ^ |
| handle.tmInternalLeading ^ handle.tmExternalLeading ^ |
| handle.tmAveCharWidth ^ handle.tmMaxCharWidth ^ handle.tmWeight ^ |
| handle.tmOverhang ^ handle.tmDigitizedAspectX ^ handle.tmDigitizedAspectY ^ |
| // handle.tmFirstChar ^ handle.tmLastChar ^ handle.tmDefaultChar ^ handle.tmBreakChar ^ |
| handle.tmItalic ^ handle.tmUnderlined ^ handle.tmStruckOut ^ |
| handle.tmPitchAndFamily ^ handle.tmCharSet; |
| } |
| |
| /** |
| * Invokes platform specific functionality to allocate a new font metrics. |
| * <p> |
| * <b>IMPORTANT:</b> This method is <em>not</em> part of the public |
| * API for <code>FontMetrics</code>. It is marked public only so that |
| * it can be shared within the packages provided by SWT. It is not |
| * available on all platforms, and should never be called from |
| * application code. |
| * </p> |
| * |
| * @param handle the <code>TEXTMETRIC</code> containing information about a font |
| * @return a new font metrics object containing the specified <code>TEXTMETRIC</code> |
| */ |
| public static FontMetrics win32_new(TEXTMETRIC handle) { |
| FontMetrics fontMetrics = new FontMetrics(); |
| fontMetrics.handle = handle; |
| return fontMetrics; |
| } |
| |
| } |