src/main/java/eu/svjatoslav/sixth/e3d/renderer/raster/shapes/basic/texturedpolygon/PolygonBorderInterpolator.java

   1 /*
   2  * Sixth 3D engine. Author: Svjatoslav Agejenko.
   3  * This project is released under Creative Commons Zero (CC0) license.
   4  */
   5 package eu.svjatoslav.sixth.e3d.renderer.raster.shapes.basic.texturedpolygon;
   6
   7 import eu.svjatoslav.sixth.e3d.geometry.Point2D;
   8
   9 public class PolygonBorderInterpolator implements
  10         Comparable<PolygonBorderInterpolator> {
  11
  12     // on-screen coordinates
  13     Point2D p1;
  14     Point2D p2;
  15     double distanceFromY1;
  16     private int height;
  17     private int width;
  18     private int absoluteHeight;
  19     private double twidth;
  20     private double theight;
  21     // texture coordinates
  22     private Point2D tp1;
  23     private Point2D tp2;
  24
  25
  26     @Override
  27     public boolean equals(final Object o) {
  28         if (o == null) return false;
  29
  30         return o instanceof PolygonBorderInterpolator && compareTo((PolygonBorderInterpolator) o) == 0;
  31     }
  32
  33     @Override
  34     public int hashCode() {
  35         int result = width;
  36         result = 31 * result + absoluteHeight;
  37         return result;
  38     }
  39
  40     @Override
  41     public int compareTo(final PolygonBorderInterpolator o) {
  42         if (absoluteHeight < o.absoluteHeight)
  43             return 1;
  44         if (absoluteHeight > o.absoluteHeight)
  45             return -1;
  46
  47         if (width < o.width)
  48             return 1;
  49         if (width > o.width)
  50             return -1;
  51
  52         return 0;
  53     }
  54
  55     public boolean containsY(final int y) {
  56
  57         if (p1.y < p2.y) {
  58             if (y >= p1.y)
  59                 return y <= p2.y;
  60         } else if (y >= p2.y)
  61             return y <= p1.y;
  62
  63         return false;
  64     }
  65
  66     public double getTX() {
  67
  68         if (height == 0)
  69             return (tp2.x + tp1.x) / 2d;
  70
  71         return tp1.x + ((twidth * distanceFromY1) / height);
  72     }
  73
  74     public double getTY() {
  75
  76         if (height == 0)
  77             return (tp2.y + tp1.y) / 2d;
  78
  79         return tp1.y + ((theight * distanceFromY1) / height);
  80     }
  81
  82     public int getX() {
  83
  84         if (height == 0)
  85             return (int) ((p2.x + p1.x) / 2d);
  86
  87         return (int) (p1.x + ((width * distanceFromY1) / height));
  88     }
  89
  90     public void setCurrentY(final int y) {
  91         distanceFromY1 = y - p1.y;
  92     }
  93
  94     public void setPoints(final Point2D p1, final Point2D p2,
  95                           final Point2D tp1, final Point2D tp2) {
  96
  97         this.p1 = p1;
  98         this.p2 = p2;
  99         this.tp1 = tp1;
 100         this.tp2 = tp2;
 101
 102         height = (int) (p2.y - p1.y);
 103         width = (int) (p2.x - p1.x);
 104         absoluteHeight = Math.abs(height);
 105
 106         twidth = tp2.x - tp1.x;
 107         theight = tp2.y - tp1.y;
 108     }
 109
 110 }