1 files changed, 308 insertions, 0 deletions
diff --git a/src/java/org/apache/fop/svg/PDFTextUtil.java b/src/java/org/apache/fop/svg/PDFTextUtil.java
new file mode 100644
index 000000000..0fb552026
--- /dev/null
+++ b/src/java/org/apache/fop/svg/PDFTextUtil.java
@@ -0,0 +1,308 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* $Id$ */
+
+package org.apache.fop.svg;
+
+import java.awt.geom.AffineTransform;
+
+import org.apache.fop.fonts.Font;
+import org.apache.fop.pdf.PDFNumber;
+import org.apache.fop.pdf.PDFText;
+
+/**
+ * Utility class for generating PDF text objects.
+ */
+public class PDFTextUtil {
+
+    /** The number of decimal places. */ 
+    private static final int DEC = 8;
+    
+    /** PDF text rendering mode: Fill text */
+    public static final int TR_FILL = 0;
+    /** PDF text rendering mode: Stroke text */
+    public static final int TR_STROKE = 1;
+    /** PDF text rendering mode: Fill, then stroke text */
+    public static final int TR_FILL_STROKE = 2;
+    /** PDF text rendering mode: Neither fill nor stroke text (invisible) */
+    public static final int TR_INVISIBLE = 3;
+    /** PDF text rendering mode: Fill text and add to path for clipping */
+    public static final int TR_FILL_CLIP = 4;
+    /** PDF text rendering mode: Stroke text and add to path for clipping */
+    public static final int TR_STROKE_CLIP = 5;
+    /** PDF text rendering mode: Fill, then stroke text and add to path for clipping */
+    public static final int TR_FILL_STROKE_CLIP = 6;
+    /** PDF text rendering mode: Add text to path for clipping */
+    public static final int TR_CLIP = 7;
+    
+    
+    private PDFGraphics2D g2d;
+    private boolean inTextObject = false;
+    private Font[] fonts;
+    private Font font;
+    private String startText;
+    private String endText;
+    private boolean useMultiByte;
+    private StringBuffer bufTJ;
+    private int textRenderingMode = 0;
+    
+    /**
+     * Main constructor.
+     * @param g2d the PDFGraphics2D instance to work with
+     */
+    public PDFTextUtil(PDFGraphics2D g2d) {
+        this.g2d = g2d;
+    }
+    
+    private void writeAffineTransform(AffineTransform at, StringBuffer sb) {
+        double[] lt = new double[6];
+        at.getMatrix(lt);
+        sb.append(PDFNumber.doubleOut(lt[0], DEC)).append(" ");
+        sb.append(PDFNumber.doubleOut(lt[1], DEC)).append(" ");
+        sb.append(PDFNumber.doubleOut(lt[2], DEC)).append(" ");
+        sb.append(PDFNumber.doubleOut(lt[3], DEC)).append(" ");
+        sb.append(PDFNumber.doubleOut(lt[4], DEC)).append(" ");
+        sb.append(PDFNumber.doubleOut(lt[5], DEC));
+    }
+
+    private void writeChar(char ch, StringBuffer sb) {
+        if (!useMultiByte) {
+            if (ch > 127) {
+                sb.append("\\").append(Integer.toOctalString((int)ch));
+            } else {
+                switch (ch) {
+                case '(':
+                case ')':
+                case '\\':
+                    sb.append("\\");
+                    break;
+                default:
+                }
+                sb.append(ch);
+            }
+        } else {
+            sb.append(PDFText.toUnicodeHex(ch));
+        }
+    }
+    
+    private void checkInTextObject() {
+        if (!inTextObject) {
+            throw new IllegalStateException("Not in text object");
+        }
+    }
+    
+    /**
+     * Called when a new text object should be started. Be sure to call setFont() before
+     * issuing any text painting commands.
+     */
+    public void beginTextObject() {
+        if (inTextObject) {
+            throw new IllegalStateException("Already in text object");
+        }
+        g2d.currentStream.write("BT\n");
+        this.inTextObject = true;
+    }
+    
+    /**
+     * Called when a text object should be ended.
+     */
+    public void endTextObject() {
+        checkInTextObject();
+        g2d.currentStream.write("ET\n");
+        this.inTextObject = false;
+        initValues();
+    }
+    
+    private void initValues() {
+        this.font = null;
+        this.textRenderingMode = TR_FILL;
+    }
+    
+    /**
+     * Creates a "q" command, pushing a copy of the entire graphics state onto the stack.
+     */
+    public void saveGraphicsState() {
+        g2d.currentStream.write("q\n");
+    }
+    
+    /**
+     * Creates a "Q" command, restoring the entire graphics state to its former value by popping
+     * it from the stack.
+     */
+    public void restoreGraphicsState() {
+        g2d.currentStream.write("Q\n");
+    }
+    
+    /**
+     * Creates a "cm" command using the current transformation as the matrix.
+     */
+    public void concatMatrixCurrentTransform() {
+        StringBuffer sb = new StringBuffer();
+        if (!g2d.getTransform().isIdentity()) {
+            writeAffineTransform(g2d.getTransform(), sb);
+            sb.append(" cm\n");
+        }
+        g2d.currentStream.write(sb.toString());
+    }
+    
+    /**
+     * Sets the current fonts for the text object. For every character, the suitable font will
+     * be selected.
+     * @param fonts the new fonts
+     */
+    public void setFonts(Font[] fonts) {
+        this.fonts = fonts;
+    }
+    
+    /**
+     * Sets the current font for the text object.
+     * @param font the new font
+     */
+    public void setFont(Font font) {
+        setFonts(new Font[] {font});
+    }
+    
+    /**
+     * Returns the current font in use.
+     * @return the current font or null if no font is currently active.
+     */
+    public Font getCurrentFont() {
+        return this.font;
+    }
+    
+    /**
+     * Sets the current font.
+     * @param f the new font to use
+     */
+    public void setCurrentFont(Font f) {
+        this.font = f;
+    }
+    
+    /**
+     * Writes a "Tf" command, setting a new current font.
+     * @param f the font to select
+     */
+    public void writeTf(Font f) {
+        checkInTextObject();
+        String fontName = f.getFontName();
+        float fontSize = (float)f.getFontSize() / 1000f;
+        g2d.currentStream.write("/" + fontName + " " + PDFNumber.doubleOut(fontSize) + " Tf\n");
+        
+        this.useMultiByte = g2d.isMultiByteFont(fontName);
+        this.startText = useMultiByte ? "<" : "(";
+        this.endText = useMultiByte ? ">" : ")";
+    }
+
+    /**
+     * Sets the text rendering mode.
+     * @param mode the rendering mode (value 0 to 7, see PDF Spec, constants: TR_*)
+     */
+    public void setTextRenderingMode(int mode) {
+        if (mode < 0 || mode > 7) {
+            throw new IllegalArgumentException(
+                    "Illegal value for text rendering mode. Expected: 0-7");
+        }
+        if (mode != this.textRenderingMode) {
+            this.textRenderingMode = mode;
+            g2d.currentStream.write(this.textRenderingMode + " Tr\n");
+        }
+    }
+    
+    /**
+     * Sets the text rendering mode.
+     * @param fill true if the text should be filled
+     * @param stroke true if the text should be stroked
+     * @param addToClip true if the path should be added for clipping
+     */
+    public void setTextRenderingMode(boolean fill, boolean stroke, boolean addToClip) {
+        int mode;
+        if (fill) {
+            mode = (stroke ? 2 : 0);
+        } else {
+            mode = (stroke ? 1 : 3);
+        }
+        if (addToClip) {
+            mode += 4;
+        }
+        setTextRenderingMode(mode);
+    }
+    
+    /**
+     * Writes a "Tm" command, setting a new text transformation matrix.
+     * @param localTransform the new text transformation matrix
+     */
+    public void writeTextMatrix(AffineTransform localTransform) {
+        StringBuffer sb = new StringBuffer();
+        writeAffineTransform(localTransform, sb);
+        sb.append(" Tm\n");
+        g2d.currentStream.write(sb.toString());
+    }
+
+    /**
+     * Selects a font from the font list suitable to display the given character.
+     * @param ch the character
+     * @return the recommended Font to use
+     */
+    public Font selectFontForChar(char ch) {
+        for (int i = 0, c = fonts.length; i < c; i++) {
+            if (fonts[i].hasChar(ch)) {
+                return fonts[i];
+            }
+        }
+        return fonts[0]; //TODO Maybe fall back to painting with shapes
+    }
+    
+    /**
+     * Writes a char to the "TJ-Buffer".
+     * @param ch the unmapped character
+     */
+    public void writeTJChar(char ch) {
+        if (bufTJ == null) {
+            bufTJ = new StringBuffer();
+        }
+        if (bufTJ.length() == 0) {
+            bufTJ.append("[").append(startText);
+        }
+        char mappedChar = font.mapChar(ch);
+        writeChar(mappedChar, bufTJ);
+    }
+
+    /**
+     * Writes a glyph adjust value to the "TJ-Buffer".
+     * @param adjust the glyph adjust value in thousands of text unit space.
+     */
+    public void adjustGlyphTJ(double adjust) {
+        bufTJ.append(endText).append(" ");
+        bufTJ.append(PDFNumber.doubleOut(adjust, DEC - 4));
+        bufTJ.append(" ");
+        bufTJ.append(startText);
+    }
+
+    /**
+     * Writes a "TJ" command, writing out the accumulated buffer with the characters and glyph
+     * positioning values. The buffer is reset afterwards.
+     */
+    public void writeTJ() {
+        if (bufTJ != null && bufTJ.length() > 0) {
+            bufTJ.append(endText).append("] TJ\n");
+            g2d.currentStream.write(bufTJ.toString());
+            bufTJ.setLength(0);
+        }
+    }
+
+}