1 /*
   2  * Copyright (c) 2017, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 package sun.java2d.marlin;
  26 
  27 final class DPathSimplifier implements DPathConsumer2D {
  28 
  29     // distance threshold in pixels (device)
  30     private static final double PIX_THRESHOLD = MarlinProperties.getPathSimplifierPixelTolerance();
  31 
  32     private static final double SQUARE_TOLERANCE = PIX_THRESHOLD * PIX_THRESHOLD;
  33 
  34     // members:
  35     private DPathConsumer2D delegate;
  36     private double cx, cy;
  37 
  38     DPathSimplifier() {
  39     }
  40 
  41     DPathSimplifier init(final DPathConsumer2D delegate) {
  42         this.delegate = delegate;
  43         return this; // fluent API
  44     }
  45 
  46     @Override
  47     public void pathDone() {
  48         delegate.pathDone();
  49     }
  50 
  51     @Override
  52     public void closePath() {
  53         delegate.closePath();
  54     }
  55 
  56     @Override
  57     public long getNativeConsumer() {
  58         return 0;
  59     }
  60 
  61     @Override
  62     public void quadTo(final double x1, final double y1,
  63                        final double xe, final double ye)
  64     {
  65         // Test if curve is too small:
  66         double dx = (xe - cx);
  67         double dy = (ye - cy);
  68 
  69         if ((dx * dx + dy * dy) <= SQUARE_TOLERANCE) {
  70             // check control points P1:
  71             dx = (x1 - cx);
  72             dy = (y1 - cy);
  73 
  74             if ((dx * dx + dy * dy) <= SQUARE_TOLERANCE) {
  75                 return;
  76             }
  77         }
  78         delegate.quadTo(x1, y1, xe, ye);
  79         // final end point:
  80         cx = xe;
  81         cy = ye;
  82     }
  83 
  84     @Override
  85     public void curveTo(final double x1, final double y1,
  86                         final double x2, final double y2,
  87                         final double xe, final double ye)
  88     {
  89         // Test if curve is too small:
  90         double dx = (xe - cx);
  91         double dy = (ye - cy);
  92 
  93         if ((dx * dx + dy * dy) <= SQUARE_TOLERANCE) {
  94             // check control points P1:
  95             dx = (x1 - cx);
  96             dy = (y1 - cy);
  97 
  98             if ((dx * dx + dy * dy) <= SQUARE_TOLERANCE) {
  99                 // check control points P2:
 100                 dx = (x2 - cx);
 101                 dy = (y2 - cy);
 102 
 103                 if ((dx * dx + dy * dy) <= SQUARE_TOLERANCE) {
 104                     return;
 105                 }
 106             }
 107         }
 108         delegate.curveTo(x1, y1, x2, y2, xe, ye);
 109         // final end point:
 110         cx = xe;
 111         cy = ye;
 112     }
 113 
 114     @Override
 115     public void moveTo(final double xe, final double ye) {
 116         delegate.moveTo(xe, ye);
 117         // starting point:
 118         cx = xe;
 119         cy = ye;
 120     }
 121 
 122     @Override
 123     public void lineTo(final double xe, final double ye) {
 124         // Test if segment is too small:
 125         double dx = (xe - cx);
 126         double dy = (ye - cy);
 127 
 128         if ((dx * dx + dy * dy) <= SQUARE_TOLERANCE) {
 129             return;
 130         }
 131         delegate.lineTo(xe, ye);
 132         // final end point:
 133         cx = xe;
 134         cy = ye;
 135     }
 136 }