--- old/src/java.desktop/share/classes/sun/java2d/marlin/MarlinTileGenerator.java	2018-02-15 13:11:15.328457775 +0100
+++ new/src/java.desktop/share/classes/sun/java2d/marlin/MarlinTileGenerator.java	2018-02-15 13:11:15.176453613 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -31,6 +31,8 @@
 
 final class MarlinTileGenerator implements AATileGenerator, MarlinConst {
 
+    private static final boolean DISABLE_BLEND = false;
+
     private static final int MAX_TILE_ALPHA_SUM = TILE_W * TILE_H * MAX_AA_ALPHA;
 
     private static final int TH_AA_ALPHA_FILL_EMPTY = ((MAX_AA_ALPHA + 1) / 3); // 33%
@@ -43,10 +45,10 @@
             throw new IllegalStateException("Invalid MAX_TILE_ALPHA_SUM: " + MAX_TILE_ALPHA_SUM);
         }
         if (DO_TRACE) {
-            System.out.println("MAX_AA_ALPHA           : " + MAX_AA_ALPHA);
-            System.out.println("TH_AA_ALPHA_FILL_EMPTY : " + TH_AA_ALPHA_FILL_EMPTY);
-            System.out.println("TH_AA_ALPHA_FILL_FULL  : " + TH_AA_ALPHA_FILL_FULL);
-            System.out.println("FILL_TILE_W            : " + FILL_TILE_W);
+            MarlinUtils.logInfo("MAX_AA_ALPHA           : " + MAX_AA_ALPHA);
+            MarlinUtils.logInfo("TH_AA_ALPHA_FILL_EMPTY : " + TH_AA_ALPHA_FILL_EMPTY);
+            MarlinUtils.logInfo("TH_AA_ALPHA_FILL_FULL  : " + TH_AA_ALPHA_FILL_FULL);
+            MarlinUtils.logInfo("FILL_TILE_W            : " + FILL_TILE_W);
         }
     }
 
@@ -141,6 +143,10 @@
      */
     @Override
     public int getTypicalAlpha() {
+        if (DISABLE_BLEND) {
+            // always return empty tiles to disable blending operations
+            return 0x00;
+        }
         int al = cache.alphaSumInTile(x);
         // Note: if we have a filled rectangle that doesn't end on a tile
         // border, we could still return 0xff, even though al!=maxTileAlphaSum