OTF: Support GposLookupType1 - table subformat 2

DEVSIX-5160

Author: Snipx

io/src/main/java/com/itextpdf/io/font/otf/GposLookupType1.java

@@ -22,6 +22,7 @@ This file is part of the iText (R) project.
  */
 package com.itextpdf.io.font.otf;
 
+import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -56,8 +57,8 @@ public boolean transformOne(GlyphLine line) {
         GposValueRecord valueRecord = valueRecordMap.get(glyphCode);
         if (valueRecord != null) {
             Glyph newGlyph = new Glyph(line.get(line.idx));
-            newGlyph.xAdvance += (short)valueRecord.XAdvance;
-            newGlyph.yAdvance += (short)valueRecord.YAdvance;
+            newGlyph.setXAdvance((short)(newGlyph.getXAdvance() + valueRecord.XAdvance));
+            newGlyph.setYAdvance((short)(newGlyph.getYAdvance() + valueRecord.YAdvance));
             line.set(line.idx, newGlyph);
             positionApplied = true;
         }
@@ -68,13 +69,28 @@ public boolean transformOne(GlyphLine line) {
     @Override
     protected void readSubTable(int subTableLocation) throws java.io.IOException {
         openReader.rf.seek(subTableLocation);
-        openReader.rf.readShort();
-        int coverage = openReader.rf.readUnsignedShort();
+        int subTableFormat = openReader.rf.readShort();
+        int coverageOffset = openReader.rf.readUnsignedShort();
         int valueFormat = openReader.rf.readUnsignedShort();
-        GposValueRecord valueRecord = OtfReadCommon.readGposValueRecord(openReader, valueFormat);
-        List<Integer> coverageGlyphIds = openReader.readCoverageFormat(subTableLocation + coverage);
-        for (Integer glyphId : coverageGlyphIds) {
-            valueRecordMap.put((int)glyphId, valueRecord);
+        if (subTableFormat == 1) {
+            GposValueRecord valueRecord = OtfReadCommon.readGposValueRecord(openReader, valueFormat);
+            List<Integer> coverageGlyphIds = openReader.readCoverageFormat(subTableLocation + coverageOffset);
+            for (Integer glyphId : coverageGlyphIds) {
+                valueRecordMap.put((int) glyphId, valueRecord);
+            }
+        } else if (subTableFormat == 2) {
+            int valueCount = openReader.rf.readUnsignedShort();
+            List<GposValueRecord> valueRecords = new ArrayList<>();
+            for (int i = 0; i < valueCount; i++) {
+                GposValueRecord valueRecord = OtfReadCommon.readGposValueRecord(openReader, valueFormat);
+                valueRecords.add(valueRecord);
+            }
+            List<Integer> coverageGlyphIds = openReader.readCoverageFormat(subTableLocation + coverageOffset);
+            for (int i = 0; i < coverageGlyphIds.size(); i++) {
+                valueRecordMap.put((int) coverageGlyphIds.get(i), valueRecords.get(i));
+            }
+        } else {
+            throw new IllegalArgumentException("Bad subtable format identifier: " + subTableFormat);
         }
     }
 }

io/src/test/java/com/itextpdf/io/font/otf/GposLookupType1Test.java

@@ -39,7 +39,7 @@ public class GposLookupType1Test extends ExtendedITextTest {
     private static final String RESOURCE_FOLDER = "./src/test/resources/com/itextpdf/io/font/otf/GposLookupType1Test/";
 
     @Test
-    public void verifyXAdvanceIsApplied() throws IOException {
+    public void verifyXAdvanceIsAppliedSubFormat1() throws IOException {
         TrueTypeFont fontProgram = (TrueTypeFont) FontProgramFactory.createFont(RESOURCE_FOLDER + "NotoSansMyanmar-Regular.ttf");
         GlyphPositioningTableReader gposTableReader = fontProgram.getGposTable();
         GposLookupType1 lookup = (GposLookupType1) gposTableReader.getLookupTable(29);
@@ -57,7 +57,7 @@ public void verifyXAdvanceIsApplied() throws IOException {
     }
 
     @Test
-    public void verifyPositionIsNotAppliedForIrrelevantGlyph() throws IOException {
+    public void verifyPositionIsNotAppliedForIrrelevantGlyphSubFormat1() throws IOException {
         TrueTypeFont fontProgram = (TrueTypeFont) FontProgramFactory.createFont(RESOURCE_FOLDER + "NotoSansMyanmar-Regular.ttf");
         GlyphPositioningTableReader gposTableReader = fontProgram.getGposTable();
         GposLookupType1 lookup = (GposLookupType1) gposTableReader.getLookupTable(29);
@@ -74,4 +74,27 @@ public void verifyPositionIsNotAppliedForIrrelevantGlyph() throws IOException {
         Assert.assertEquals(0, gl.get(0).getXAdvance());
     }
 
+    @Test
+    public void verifyDifferentXAdvanceIsAppliedSubFormat2() throws IOException {
+        TrueTypeFont fontProgram = (TrueTypeFont) FontProgramFactory.createFont(RESOURCE_FOLDER + "NotoSansMyanmar-Regular.ttf");
+        GlyphPositioningTableReader gposTableReader = fontProgram.getGposTable();
+        GposLookupType1 lookup = (GposLookupType1) gposTableReader.getLookupTable(16);
+
+        List<Glyph> glyphs = Arrays.asList(new Glyph(fontProgram.getGlyphByCode(401)),
+                new Glyph(fontProgram.getGlyphByCode(5)));
+        GlyphLine gl = new GlyphLine(glyphs);
+        Assert.assertEquals(0, gl.get(0).getXAdvance());
+        Assert.assertTrue(lookup.transformOne(gl));
+        Assert.assertEquals(109, gl.get(0).getXAdvance());
+
+        // Subtable type 2 defines different GposValueRecords for different coverage glyphs
+
+        glyphs = Arrays.asList(new Glyph(fontProgram.getGlyphByCode(508)),
+                new Glyph(fontProgram.getGlyphByCode(5)));
+        gl = new GlyphLine(glyphs);
+        Assert.assertEquals(0, gl.get(0).getXAdvance());
+        Assert.assertTrue(lookup.transformOne(gl));
+        Assert.assertEquals(158, gl.get(0).getXAdvance());
+    }
+
 }