line.java

来自「ErGo是一个很早的Java通用围棋服务器(IGS/NNGS)客户端程序。有全部」· Java 代码 · 共 117 行

package ergo.ui;

// $Id: Line.java,v 1.3 1999/08/15 01:40:28 sigue Exp $

/*
 *  Copyright (C) 1999  Carl L. Gay and Antranig M. Basman.
 *  See the file copyright.txt, distributed with this software,
 *  for further information.
 */

class Line {
  int d;			// this is mod 2*v1 (x-coord).
  int x0, y0;			// 0-based current coordinates.
  int v1, v2;			// 0-based target.
  boolean up = false;
  ZappoMat zm = new ZappoMat();
  public void brezinit(int x1, int y1, int x2, int y2) {
//    String s = " ";
//    System.out.println("Brezinit: "+x1+s+x2+s+x2+s+y2);
    zm.setorig(x1, y1);
    v1 = x2 - x1;
    v2 = y2 - y1;
    x0 = 0; y0 = 0;
    if (v1 < 0) zm.compose (-1,0,0,1);
    if (v2 < 0) zm.compose (1,0,0,-1);
    v1 = v1*zm.a; v2 = v2*zm.d;
    if (v2 > v1) {
      zm.compose(0,1,1,0);
      int t = v1; v1 = v2; v2 = t;
    }
    d = v1;
    if (zm.weirdo()==1) up = true;
    else up = false;
//    System.out.println(up);
    //    System.out.println(zm);
    //    System.out.println(zm.weirdo());
  }
  public void copy (Line other) {
    d = other.d; x0 = other.x0; y0 = other.y0;
    v1 = other.v1; v2 = other.v2;
    up = other.up;
    zm.copy(other.zm);
  }
  public boolean breznext() {
    ++x0;
    //  System.out.println(v1);
    if (x0 > v1) return false;
    d += 2*v2;
    if (d>2*v1 || up && d==2*v1) {
      d -= 2*v1;
      ++y0;
    }
//       System.out.println("X: "+x0+" Y: "+y0+" D: "+d);
    return true;
  }
  public int waity(int reqy) {
    int lastx = 0;
//    System.out.println("Init Wait for "+reqy+", at "+zm.getx(x0,y0)+", "+zm.gety(x0,y0));
    while (zm.gety(x0, y0) == reqy) {
      lastx = zm.getx(x0, y0);
//      System.out.println("Wait for "+reqy+", at "+zm.getx(x0,y0)+", "+zm.gety(x0,y0));
      if (!breznext()) {
	System.out.println("Error: required wait for "+reqy+", got to "+zm.gety(x0,y0));
	break;
      }
    }
    return lastx;
  }
  public void line(RawImage imag, int color, int x1, int y1, int x2, int y2) {
    brezinit(x1, y1, x2, y2);
    do {
      zm.setZapPixel(imag, color, x0, y0);
    }
    while (breznext());
  }

  class ZappoMat {
    int a=1, b=0, c=0, d=1;
    // premultiply.....! want first things to happen first....
    ZappoMat compose(int a1, int b1, int c1, int d1) {
      int a2 = a1*a + b1*c; int b2 = a1*b + b1*d;
      int c2 = c1*a + d1*c; int d2 = b1*c + d1*d;
      a = a2; b = b2; c = c2; d = d2;
      return this;
    }
    int xorig, yorig;
    void init() {
      a=1; b=0; c=0; d=1;
    }
    int weirdo() {
      return a+b;
    }
    void setorig(int xorig1, int yorig1) {
      init();
      xorig = xorig1; yorig = yorig1;
    }
    void setZapPixel(RawImage imag, int color, int x, int y) {
      int x3 = xorig + (a*x + c*y); int y3 = yorig + (b*x + d*y);
      //    System.out.println("Trans: x="+x3+", y="+y3);
      imag.setpixel(color, x3, y3);
    }
    int gety(int x, int y) {
      return yorig + (b*x + d*y);
    }
    int getx(int x, int y) {
      return xorig + (a*x + c*y);
    }
    public String toString() {
      return ""+a+" "+b+" "+c+" "+d;
    }
    void copy(ZappoMat other) {
      a = other.a; b = other.b; c = other.c; d = other.d;
      xorig = other.xorig; yorig = other.yorig;
    }
  } // end inner class ZappoMat
}