enhanced graph shifting

src/app/services/graph.service.ts

@@ -0,0 +1,76 @@
+import { Validators } from '@angular/forms';
+/**
+ * Copyright (C) 2018 Michael Czechowski <mail@dailysh.it>
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; version 2.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+import { Inject, Injectable, Renderer2, RendererFactory2 } from '@angular/core';
+import * as Selection from 'd3-selection';
+
+import { MathService } from './math.service';
+import { Graph } from './../models/graph.model';
+import { Point } from './../models/point.model';
+
+@Injectable()
+export class GraphService {
+  private graphs: Graph[];
+  private animation: boolean | null;
+
+  constructor(
+    private math: MathService
+  ) {}
+
+  public get() {
+    return this.graphs;
+  }
+
+  public set(newGraphs: Graph[]) {
+    // console.log('GraphService:set', newGraphs);
+    this.graphs = newGraphs;
+  }
+
+  public get isAnimated() {
+    return this.animation;
+  }
+
+  public startAnimation() {
+    this.animation = true;
+  }
+
+  public stopAnimation() {
+    this.animation = false;
+  }
+
+  public *spreadOrthogonal(start: Point, spacing: number) {
+    const sign = this.math.flipSign();
+    let currentPoint = start;
+    let i = 0;
+
+    while (true) {
+      const currentSpacing = sign.next().value * spacing * i;
+      currentPoint = this.shiftPoint(currentPoint, start.ascent, currentSpacing);
+
+      yield currentPoint;
+
+      i++;
+    }
+  }
+
+  public shiftPoint(point: Point, radians: number, spacing: number) {
+    return {
+      x: Math.sin(radians * Math.PI) * spacing + point.x,
+      y: Math.cos(radians * Math.PI) * spacing + point.y
+    };
+  }
+}