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 import sun.awt.geom.PathConsumer2D;
  28 
  29 final class PathSimplifier implements PathConsumer2D {
  30 
  31     // distance threshold in pixels (device)
  32     private static final float PIX_THRESHOLD = MarlinProperties.getPathSimplifierPixelTolerance();
  33 
  34     private static final float SQUARE_TOLERANCE = PIX_THRESHOLD * PIX_THRESHOLD;
  35 
  36     // members:
  37     private PathConsumer2D delegate;
  38     private float cx, cy;
  39 
  40     PathSimplifier() {
  41     }
  42 
  43     PathSimplifier init(final PathConsumer2D delegate) {
  44         this.delegate = delegate;
  45         return this; // fluent API
  46     }
  47 
  48     @Override
  49     public void pathDone() {
  50         delegate.pathDone();
  51     }
  52 
  53     @Override
  54     public void closePath() {
  55         delegate.closePath();
  56     }
  57 
  58     @Override
  59     public long getNativeConsumer() {
  60         return 0;
  61     }
  62 
  63     @Override
  64     public void quadTo(final float x1, final float y1,
  65                        final float xe, final float ye)
  66     {
  67         // Test if curve is too small:
  68         float dx = (xe - cx);
  69         float dy = (ye - cy);
  70 
  71         if ((dx * dx + dy * dy) <= SQUARE_TOLERANCE) {
  72             // check control points P1:
  73             dx = (x1 - cx);
  74             dy = (y1 - cy);
  75 
  76             if ((dx * dx + dy * dy) <= SQUARE_TOLERANCE) {
  77                 return;
  78             }
  79         }
  80         delegate.quadTo(x1, y1, xe, ye);
  81         // final end point:
  82         cx = xe;
  83         cy = ye;
  84     }
  85 
  86     @Override
  87     public void curveTo(final float x1, final float y1,
  88                         final float x2, final float y2,
  89                         final float xe, final float ye)
  90     {
  91         // Test if curve is too small:
  92         float dx = (xe - cx);
  93         float dy = (ye - cy);
  94 
  95         if ((dx * dx + dy * dy) <= SQUARE_TOLERANCE) {
  96             // check control points P1:
  97             dx = (x1 - cx);
  98             dy = (y1 - cy);
  99 
 100             if ((dx * dx + dy * dy) <= SQUARE_TOLERANCE) {
 101                 // check control points P2:
 102                 dx = (x2 - cx);
 103                 dy = (y2 - cy);
 104 
 105                 if ((dx * dx + dy * dy) <= SQUARE_TOLERANCE) {
 106                     return;
 107                 }
 108             }
 109         }
 110         delegate.curveTo(x1, y1, x2, y2, xe, ye);
 111         // final end point:
 112         cx = xe;
 113         cy = ye;
 114     }
 115 
 116     @Override
 117     public void moveTo(final float xe, final float ye) {
 118         delegate.moveTo(xe, ye);
 119         // starting point:
 120         cx = xe;
 121         cy = ye;
 122     }
 123 
 124     @Override
 125     public void lineTo(final float xe, final float ye) {
 126         // Test if segment is too small:
 127         float dx = (xe - cx);
 128         float dy = (ye - cy);
 129 
 130         if ((dx * dx + dy * dy) <= SQUARE_TOLERANCE) {
 131             return;
 132         }
 133         delegate.lineTo(xe, ye);
 134         // final end point:
 135         cx = xe;
 136         cy = ye;
 137     }
 138 }