summaryrefslogtreecommitdiff
path: root/libjava/classpath/java/awt/font/TextMeasurer.java
diff options
context:
space:
mode:
authorupstream source tree <ports@midipix.org>2015-03-15 20:14:05 -0400
committerupstream source tree <ports@midipix.org>2015-03-15 20:14:05 -0400
commit554fd8c5195424bdbcabf5de30fdc183aba391bd (patch)
tree976dc5ab7fddf506dadce60ae936f43f58787092 /libjava/classpath/java/awt/font/TextMeasurer.java
downloadcbb-gcc-4.6.4-554fd8c5195424bdbcabf5de30fdc183aba391bd.tar.bz2
cbb-gcc-4.6.4-554fd8c5195424bdbcabf5de30fdc183aba391bd.tar.xz
obtained gcc-4.6.4.tar.bz2 from upstream website;upstream
verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository.
Diffstat (limited to 'libjava/classpath/java/awt/font/TextMeasurer.java')
-rw-r--r--libjava/classpath/java/awt/font/TextMeasurer.java190
1 files changed, 190 insertions, 0 deletions
diff --git a/libjava/classpath/java/awt/font/TextMeasurer.java b/libjava/classpath/java/awt/font/TextMeasurer.java
new file mode 100644
index 000000000..e443e8bc7
--- /dev/null
+++ b/libjava/classpath/java/awt/font/TextMeasurer.java
@@ -0,0 +1,190 @@
+/* TextMeasurer.java
+ Copyright (C) 2006 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath 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 2, or (at your option)
+any later version.
+
+GNU Classpath 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 GNU Classpath; see the file COPYING. If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library. Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module. An independent module is a module which is not derived from
+or based on this library. If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so. If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package java.awt.font;
+
+import java.text.AttributedCharacterIterator;
+import java.awt.Shape;
+
+/**
+ * TextMeasurer is a small utility class for measuring the length of laid-out
+ * text objects.
+ *
+ * @author Sven de Marothy
+ * @since 1.3
+ */
+public final class TextMeasurer implements Cloneable
+{
+ private AttributedCharacterIterator text;
+ private FontRenderContext frc;
+ private TextLayout totalLayout;
+ private int numChars;
+
+ /**
+ * Creates a TextMeasurer from a given text in the form of an
+ * <code>AttributedCharacterIterator</code> and a
+ * <code>FontRenderContext</code>.
+ */
+ public TextMeasurer (AttributedCharacterIterator text, FontRenderContext frc)
+ {
+ this.text = text;
+ this.frc = frc;
+ totalLayout = new TextLayout( text, frc );
+ numChars = totalLayout.getCharacterCount();
+ }
+
+ /**
+ * Clones the TextMeasurer object
+ */
+ protected Object clone ()
+ {
+ return new TextMeasurer( text, frc );
+ }
+
+ /**
+ * Update the text if a character is deleted at the position deletePos
+ * @param newParagraph - the updated paragraph.
+ * @param deletePos - the deletion position
+ */
+ public void deleteChar (AttributedCharacterIterator newParagraph,
+ int deletePos)
+ {
+ totalLayout = new TextLayout(newParagraph, frc);
+ if( deletePos < 0 || deletePos > totalLayout.getCharacterCount() )
+ throw new NullPointerException("Invalid deletePos:"+deletePos);
+ numChars = totalLayout.getCharacterCount();
+ text = newParagraph;
+ }
+
+ /**
+ * Update the text if a character is inserted at the position insertPos
+ * @param newParagraph - the updated paragraph.
+ * @param insertPos - the insertion position
+ */
+ public void insertChar (AttributedCharacterIterator newParagraph,
+ int insertPos)
+ {
+ totalLayout = new TextLayout(newParagraph, frc);
+ if( insertPos < 0 || insertPos > totalLayout.getCharacterCount() )
+ throw new NullPointerException("Invalid insertPos:"+insertPos);
+ numChars = totalLayout.getCharacterCount();
+ text = newParagraph;
+ }
+
+ /***
+ * Returns the total advance between two positions in the paragraph.
+ * Characters from start to limit-1 (inclusive) are included in this count.
+ *
+ * @param start - the starting character index.
+ * @param limit - the limiting index.
+ */
+ public float getAdvanceBetween (int start, int limit)
+ {
+ Shape s = totalLayout.getLogicalHighlightShape( start, limit );
+ return (float)s.getBounds2D().getWidth();
+ }
+
+ /**
+ * Returns a <code>TextLayout</code> object corresponding to the characters
+ * from text to limit.
+ * @param start - the starting character index.
+ * @param limit - the limiting index.
+ */
+ public TextLayout getLayout (int start, int limit)
+ {
+ if( start >= limit )
+ throw new IllegalArgumentException("Start position must be < limit.");
+ return new TextLayout( totalLayout, start, limit );
+ }
+
+ /**
+ * Returns the line-break index from a given starting index and a maximum
+ * advance. The index returned is the first character outside the given
+ * advance (or the limit of the string, if all remaining characters fit.)
+ *
+ * @param start - the starting index.
+ * @param maxAdvance - the maximum advance allowed.
+ * @return the index of the first character beyond maxAdvance, or the
+ * index of the last character + 1.
+ */
+ public int getLineBreakIndex (int start, float maxAdvance)
+ {
+ if( start < 0 )
+ throw new IllegalArgumentException("Start parameter must be > 0.");
+
+ double remainingLength = getAdvanceBetween( start, numChars );
+
+ int guessOffset = (int)( ( (double)maxAdvance / (double)remainingLength)
+ * ( (double)numChars - (double)start ) );
+ guessOffset += start;
+ if( guessOffset > numChars )
+ guessOffset = numChars;
+
+ double guessLength = getAdvanceBetween( start, guessOffset );
+ boolean makeSmaller = ( guessLength > maxAdvance );
+ int inc = makeSmaller ? -1 : 1;
+ boolean keepGoing = true;
+
+ do
+ {
+ guessOffset = guessOffset + inc;
+ if( guessOffset <= start || guessOffset > numChars )
+ {
+ keepGoing = false;
+ }
+ else
+ {
+ guessLength = getAdvanceBetween( start, guessOffset );
+ if( makeSmaller && ( guessLength <= maxAdvance) )
+ keepGoing = false;
+ if( !makeSmaller && ( guessLength >= maxAdvance) )
+ keepGoing = false;
+ }
+ }
+ while( keepGoing );
+
+ // Return first index that doesn't fit.
+ if( !makeSmaller )
+ guessOffset--;
+
+ if( guessOffset > numChars )
+ return numChars;
+
+ return guessOffset;
+ }
+}