Base

app/Helper/Line.php

@@ -0,0 +1,61 @@
+<?php
+namespace App\Helper;
+
+class Line
+{
+  protected $origin;
+  protected $length;
+  protected $direction;
+
+  public function __construct($point_a, $point_b)
+  {
+    $this->origin = $point_a;
+    $this->length = $this->distance($point_a, $point_b);
+    $this->direction = $this->gradient($point_a, $point_b);
+  }
+  public function origin()
+  {
+    return $this->origin;
+  }
+  public function length()
+  {
+    return $this->length;
+  }
+  public function direction()
+  {
+    return $this->direction;
+  }
+  /**
+   * Calculate the gradient to move from point a to point b
+   * @param  array $point_a [Vector]
+   * @param  array $point_b [Vector]
+   * @return array          [Vector]
+   */
+  public function gradient($point_a, $point_b)
+  {
+    $distance = $this->distance($point_a, $point_b);
+    return array_map(function($a, $b) use ($distance) {
+      return ($a - $b) / $distance;
+    }, $point_b, $point_a);
+  }
+  // sqrt((a0-b0)²+(a1-b1)²+(a2-b2)²)
+  public function distance($point_a, $point_b)
+  {
+    return sqrt(array_sum(array_map(function($a, $b) {
+      return pow($a - $b, 2);
+    }, $point_a, $point_b)));
+  }
+  /**
+   * Move from point in the direction of the gradient acording to step_size
+   * @param  array $point     [Vector]
+   * @param  int $step_size [step size]
+   * @return array            [Vector]
+   */
+  public function move($point, $step_size)
+  {
+    $gradient = $this->direction;
+    return array_map(function($a, $b) use ($step_size) {
+      return $a + $b * $step_size;
+    }, $point, $gradient);
+  }
+}