*/
package org.apache.fop.area;
+import java.awt.Font;
+import java.awt.font.FontRenderContext;
+import java.awt.font.TextAttribute;
+import java.awt.font.TextLayout;
+import java.awt.font.TextMeasurer;
+import java.text.AttributedCharacterIterator;
+import java.text.AttributedString;
+import java.util.Map;
+
import org.apache.fop.datastructs.Node;
-import org.apache.fop.fo.FONode;
+import org.apache.fop.datatypes.TextDecorations;
+import org.apache.fop.fo.FOPageSeqNode;
+import org.apache.fop.fo.expr.PropertyException;
import org.apache.fop.fo.flow.FoPageSequence;
+import org.apache.fop.fonts.FontException;
/**
+ * <code>LineArea</code>s are <code>BlockArea</code>s constructed
+ * automatically from a series of <code>InlineArea</code>s. They are
+ * stacked within the area generated by the block parent of the sequence
+ * of inlines; e.g. <code>fo:block</code> containing <code>PCDATA</code>.
+ * <p>In addition to normal dimensions, a <code>LineArea</code> has a
+ * <i>leading</i>, or baseline-to-baseline spacing, an <i>ascent</i> and a
+ * <i>descent</i>, both relative to its baseline. These are available
+ * through the <code>TextLayout</code> object. The impact of a new
+ * <code>LineArea</code> on the <code>block-progression-dimension</code>
+ * is illustrated below.
+ * <img src="doc-files/LineAreas.png">
+ *
* @author pbw
* @version $Revision$ $Name$
*/
public class LineArea extends BlockArea {
+
+ private String text;
+
/**
- * @param pageSeq
- * @param generatedBy
- * @param parent
- * @param sync
+ * @param text the text of the generating Flow Object
+ * @param pageSeq the ancestor page-sequence
+ * @param generatedBy the generating Flow Object
+ * @param parent the parent <code>Area</code> of this <code>Area</code>
+ * @param sync the synchronization object of this node
*/
- public LineArea(FoPageSequence pageSeq, FONode generatedBy, Node parent,
- Object sync) {
+ public LineArea(String text, FoPageSequence pageSeq,
+ FOPageSeqNode generatedBy, Node parent, Object sync) {
super(pageSeq, generatedBy, parent, sync);
- // TODO Auto-generated constructor stub
+ generator = generatedBy;
+ this.text = text;
+ try {
+ preprocessText();
+ } catch (PropertyException e) {
+ throw new RuntimeException(e);
+ } catch (FontException e) {
+ throw new RuntimeException(e);
+ }
+ }
+
+ /** <code>generatedBy</code> as an <code>FOPageSeqNode</code> */
+ protected FOPageSeqNode generator;
+ /** The <code>Map</code> of <code>Font</code> attributes. */
+ private Map attributes;
+ /**
+ * Gets the <code>Map</code> of <code>Font</code> attributes
+ * @return the map
+ */
+ public Map getAttributes() {
+ return attributes;
+ }
+ /** The font for this text. */
+ private Font font;
+ /**
+ * Gets the <code>Font</code>for this text
+ * @return the font
+ */
+ public Font getFont() {
+ return font;
+ }
+ /** The <code>PCDATA</code> in an <code>AttributedString</code> */
+ private AttributedString attText;
+ /**
+ * Gets the attributed text
+ * @return the attributed text
+ */
+ public AttributedString getAttributedText() {
+ return attText;
+ }
+ /** The <code>TextMeasurer</code> generated from the text */
+ private TextMeasurer measurer;
+ /**
+ * Gets the <code>TextMeasurer</code> generated from the text
+ * @return the measurer
+ */
+ public TextMeasurer getMeasurer() {
+ return measurer;
}
+ /** The <code>TextLayout</code> generated from the text */
+ private TextLayout layout;
+ /**
+ * Gets the <code>TextLayout</code> generated from the text
+ * @return the layout
+ */
+ public TextLayout getLayout() {
+ return layout;
+ }
+ public static final boolean IS_ANTI_ALIASED = true;
+ public static final boolean USES_FRACTIONAL_METRICS = true;
+ // PCDATA provides sequences of inline-areas to fill line-areas in the
+ // parent block area.
+ // Generate a text-layout for the PCDATA.
+ /**
+ * Generates a TextMeasurer from the PCDATA text. The font and text
+ * attributes of the text are applied.
+ */
+ private void preprocessText() throws PropertyException, FontException {
+ // Get the font, size, style and weight attributes
+ attributes = generator.getFontAttributes();
+ font = generator.getFopFont(attributes);
+ TextDecorations decorations = generator.getDecorations();
+ // Add the text decorations
+ // TODO separate color support for text decorations
+ if (decorations.underlined()) {
+ attributes.put(TextAttribute.UNDERLINE,
+ TextAttribute.UNDERLINE_LOW_ONE_PIXEL);
+ }
+ if (decorations.overlined()) {
+ // Not supported yet
+ }
+ if (decorations.struckthrough()) {
+ attributes.put(TextAttribute.STRIKETHROUGH,
+ TextAttribute.STRIKETHROUGH_ON);
+ }
+ attText = new AttributedString(text, attributes);
+ AttributedCharacterIterator iter = attText.getIterator();
+ FontRenderContext identityFRC =
+ new FontRenderContext(
+ null, IS_ANTI_ALIASED, USES_FRACTIONAL_METRICS);
+ measurer = new TextMeasurer(iter, identityFRC);
+ layout = new TextLayout(iter, identityFRC);
+ // Find minima and maxima for this text
+ // Text dimensions based on baseline-to-baseline leading and the
+ // descent of the TextLayout
+ // Maximum BPDim for text is dependent on the descent of the
+ // previous line. (See diagram in class description). As an
+ // approximation, the larger of the leading and ascent + descent is
+ // used.
+ // The maximum IPDim is the advance of the complete text.
+ // To determine the minima, the shortest length of text is determined,
+ // a TextLayout is formed from that, and the corresponding BPDim and
+ // IPDim values are determined.
+ iPDimMax = new Float(layout.getVisibleAdvance());
+ bPDimMax =
+ new Float(Math.max(
+ layout.getLeading(),
+ (layout.getAscent() + layout.getDescent())));
+ // Find the shortest fragment of the text
+ // TODO work out Locale handling
+ }
+
}
projects / xmlgraphics-fop.git / commitdiff