PDFPainter updated for transparency text processing, metanorma/metano…

…rma-bipm#188
metanorma · Aug 19, 2022 · cb706b2 · cb706b2
1 parent 5b0d989
commit cb706b2
Showing 1 changed file with 9 additions and 2 deletions.
diff --git a/src/main/java/org/apache/fop/render/pdf/PDFPainter.java b/src/main/java/org/apache/fop/render/pdf/PDFPainter.java
@@ -467,7 +467,12 @@ private void drawTextWithDX(int x, int y, String text, FontTriplet triplet,
 
         double shear = 0;
         boolean simulateStyle = tf instanceof CustomFont && ((CustomFont) tf).getSimulateStyle();
-        if (simulateStyle) {
+
+        boolean isTransparent = state.getTextColor().getAlpha() == 0;
+
+        if (isTransparent) {
+            textutil.setTextRenderingMode(PDFTextUtil.TR_INVISIBLE); // set transparent mode '3 Tr'
+        } else if (simulateStyle) {
             if (triplet.getWeight() == 700) {
                 generator.add("q\n");
                 generator.add("2 Tr 0.31543 w\n");
@@ -528,7 +533,9 @@ private void drawTextWithDX(int x, int y, String text, FontTriplet triplet,
 
         }
         textutil.writeTJ();
-        if (simulateStyle && triplet.getWeight() == 700) {
+        if (isTransparent) {
+            textutil.setTextRenderingMode(PDFTextUtil.TR_FILL); //restore default mode
+        } else if (simulateStyle && triplet.getWeight() == 700) {
             generator.add("Q\n");
         }
     }