Форумы GIS-Lab.info

Код: Выделить всё

function testPos() {
  var line = [[51.503844,-0.266659],[51.504226,-0.266873]];
  var points = [{c:[51.503874,-0.266653], l:'327'}, {c:[51.504139,-0.266791], l:'339'}, {c:[51.504190,-0.266882], l:'328'}, {c:[51.503852,-0.266718], l:'324'}];

  for (var i = 0; i < points.length; i++) {
    var pt = points[i];
    console.log(pt.l);
    var p0 = line[0];
    var p1 = line[1];
    var a = {
      x: p1[0] - p0[0],
      y: p1[1] - p0[1]
    };
    var b = {
      x: pt.c[0] - p0[0],
      y: pt.c[1] - p0[1]
    };
    var func = a.x * b.y - b.x * a.y;
    if (func > 0) {
      if (((a.x * b.x) < 0) || ((a.y * b.y) < 0)) {
        console.log('Point behind and left');

      } else if ((Math.sqrt(a.x * a.x + a.y * a.y)) < (Math.sqrt(b.x * b.x + b.y * b.y))) {
        console.log('Point beyond and left');

      } else {
        console.log('Point left');

      }
    } else if (func < 0) {
      if (((a.x * b.x) < 0) || ((a.y * b.y) < 0)) {
        console.log('Point behind and right');

      } else if ((Math.sqrt(a.x * a.x + a.y * a.y)) < (Math.sqrt(b.x * b.x + b.y * b.y))) {
        console.log('Point beyond and right');

      } else {
        console.log('Point right');
        
      }
    } else {
      console.log('other');
    }
  }
}

Код: Выделить всё

if (((a.x * b.x) < 0) || ((a.y * b.y) < 0)) { }

Код: Выделить всё

if ((Math.sqrt(a.x * a.x + a.y * a.y)) < (Math.sqrt(b.x * b.x + b.y * b.y))) { }