diff --git a/package.json b/package.json
index ce92a21..f3df2d0 100644
--- a/package.json
+++ b/package.json
@@ -29,7 +29,7 @@
   ],
   "scripts": {
     "ng": "ng",
-    "start": "ng serve",
+    "start": "ng serve --aot -o",
     "build": "ng build --prod",
     "test": "ng test",
     "lint": "ng lint",
diff --git a/src/app/app.component.html b/src/app/app.component.html
index a651ac9..dfccfcb 100644
--- a/src/app/app.component.html
+++ b/src/app/app.component.html
@@ -99,8 +99,8 @@
           Animation
         </label>
         <div class="btn-group" role="group" aria-label="Basic example">
-          <button type="button" class="btn" (click)="animationActive = true" [ngClass]="{'btn-outline-primary': !animationActive, 'btn-primary': animationActive}">An</button>
-          <button type="button" class="btn" (click)="animationActive = false" [ngClass]="{'btn-outline-primary': animationActive, 'btn-primary': !animationActive}">Aus</button>
+          <button type="button" class="btn" (click)="startAnimation()" [ngClass]="{'btn-outline-primary': !animationActive, 'btn-primary': animationActive}">An</button>
+          <button type="button" class="btn" (click)="stopAnimation()" [ngClass]="{'btn-outline-primary': animationActive, 'btn-primary': !animationActive}">Aus</button>
         </div>
       </div>
       <div class="dropdown-divider mb-4"></div>
diff --git a/src/app/app.component.ts b/src/app/app.component.ts
index 17b03dc..ceed6a5 100644
--- a/src/app/app.component.ts
+++ b/src/app/app.component.ts
@@ -1,4 +1,3 @@
-import { AnimationService } from './services/animation.service';
 /**
  * Copyright (C) 2018 Michael Czechowski <mail@dailysh.it>
  * This program is free software; you can redistribute it and/or modify it
@@ -29,6 +28,8 @@ import { Config } from './models/config.model';
 import { CanvasService } from './services/canvas.service';
 import { HistoryService } from './services/history.service';
 import { Graph } from './models/graph.model';
+import { GraphService } from './services/graph.service';
+import { AnimationService } from './services/animation.service';
 
 @Component({
   selector: 'app-root',
@@ -49,6 +50,7 @@ export class AppComponent implements OnInit {
   constructor(
     private canvasService: CanvasService,
     private historyService: HistoryService,
+    private graphService: GraphService,
   ) {
     moment.locale('de');
 
@@ -100,4 +102,14 @@ export class AppComponent implements OnInit {
     this.configForm.reset({...history.config});
     this.restoredHistory = history;
   }
+
+  public startAnimation() {
+    this.animationActive = true;
+    this.graphService.startAnimation();
+  }
+
+  public stopAnimation() {
+    this.animationActive = false;
+    this.graphService.stopAnimation();
+  }
 }
diff --git a/src/app/app.module.ts b/src/app/app.module.ts
index 7307278..1d87154 100644
--- a/src/app/app.module.ts
+++ b/src/app/app.module.ts
@@ -25,7 +25,8 @@ import { GuillocheDirective } from './directives/guilloche.directive';
 import { CanvasService } from './services/canvas.service';
 import { HistoryService } from './services/history.service';
 import { AnimationService } from './services/animation.service';
-import { ArithmeticService } from './services/arithmetic.service';
+import { MathService } from './services/math.service';
+import { GraphService } from './services/graph.service';
 
 @NgModule({
   declarations: [
@@ -43,7 +44,8 @@ import { ArithmeticService } from './services/arithmetic.service';
     CanvasService,
     HistoryService,
     AnimationService,
-    ArithmeticService,
+    MathService,
+    GraphService,
   ],
   bootstrap: [AppComponent]
 })
diff --git a/src/app/components/graphs.component.html b/src/app/components/graphs.component.html
index 37a7bbd..389ac28 100644
--- a/src/app/components/graphs.component.html
+++ b/src/app/components/graphs.component.html
@@ -1,3 +1,5 @@
 <svg #svg width="100%" height="100%">
-  <g guilloche *ngFor="let graph of graphs" [graph]="graph" [matrix]="matrix" [config]="config" (guillocheChange)="prepareGuillocheExport($event)"></g>
+  <g guilloche [graph]="graphs[0]" [matrix]="matrix" [config]="config" [animate]="true" (guillocheChange)="prepareGuillocheExport($event)"></g>
+  <g guilloche [graph]="graphs[1]" [matrix]="matrix" [config]="config" [animate]="true" (guillocheChange)="prepareGuillocheExport($event)"></g>
+  <!-- <g guilloche *ngFor="let graph of graphs" [graph]="graph" [matrix]="matrix" [config]="config" [animate]="true" (guillocheChange)="prepareGuillocheExport($event)"></g> -->
 </svg>
diff --git a/src/app/components/graphs.component.ts b/src/app/components/graphs.component.ts
index 59e6d26..195fd39 100644
--- a/src/app/components/graphs.component.ts
+++ b/src/app/components/graphs.component.ts
@@ -25,10 +25,11 @@ import { environment as env } from '../../environments/environment';
 import { CanvasService } from './../services/canvas.service';
 import { HistoryService } from './../services/history.service';
 import { AnimationService } from '../services/animation.service';
-import { ArithmeticService } from '../services/arithmetic.service';
+import { MathService } from '../services/math.service';
 import { GuillocheDirective } from './../directives/guilloche.directive';
 import { Graph } from '../models/graph.model';
 import { Point } from '../models/point.model';
+import { GraphService } from '../services/graph.service';
 
 @Component({
   selector: 'app-graphs',
@@ -48,7 +49,6 @@ export class GraphsComponent implements OnChanges, OnInit {
   private hash: string;
   private animation: Observable<Graph[]>;
   private timer: Observable<number>;
-  private animationSteps: any;
 
   @Input() config: any;
   @Input() restoredHistory: any;
@@ -66,7 +66,8 @@ export class GraphsComponent implements OnChanges, OnInit {
     private canvasService: CanvasService,
     private historyService: HistoryService,
     private animationService: AnimationService,
-    private arithmetics: ArithmeticService
+    private math: MathService,
+    private graphService: GraphService
   ) {
     this.genLoadedAllGraphs = this.countLoadedGraphs();
     this.timer = interval(500);
@@ -90,19 +91,6 @@ export class GraphsComponent implements OnChanges, OnInit {
       this.graphs = this.restoredHistory.graphs;
       this.hash = this.restoredHistory.hash;
     }
-
-    if (changes.animationActive) {
-      if (this.animationActive) {
-        this.animationSteps = setInterval(() => this.animateGraph(), 50);
-      } else {
-        if (this.animationSteps) {
-          clearInterval(this.animationSteps);
-        }
-      }
-    }
-  }
-  private animateGraph() {
-    this.graphs = this.animationService.animate(this.graphs);
   }
 
   private saveHistory() {
@@ -110,6 +98,10 @@ export class GraphsComponent implements OnChanges, OnInit {
     this.historyService.save(this.graphs, this.config);
   }
 
+  private saveGraph() {
+    this.graphService.set(this.graphs);
+  }
+
   private updateGraphs(): void {
     const genShiftStart = this.shiftPoint(this.matrix.start, this.config.vectors.start);
     const genShiftEnd = this.shiftPoint(this.matrix.end, this.config.vectors.end);
@@ -130,6 +122,7 @@ export class GraphsComponent implements OnChanges, OnInit {
     this.graphs = curveList.map(curve => this.adjustGraph(curve));
     this.hash = this.historyService.hash(this.graphs);
     this.saveHistory();
+    this.saveGraph();
   }
 
   private adjustGraph(curve) {
@@ -147,7 +140,7 @@ export class GraphsComponent implements OnChanges, OnInit {
     const generatedPoints = [];
 
     for (let i = 0; i < this.config.nodes; i++) {
-      generatedPoints.push(this.arithmetics.randomPoint(this.matrix, this.config.overlap));
+      generatedPoints.push(this.math.randomPoint(this.matrix, this.config.overlap));
     }
 
     return generatedPoints;
@@ -165,13 +158,13 @@ export class GraphsComponent implements OnChanges, OnInit {
 
   private updateMatrix() {
     const totalArea = Math.abs(this.canvas.clientWidth * this.canvas.clientHeight);
-    const totalCenter = this.arithmetics.centerPoint(this.canvas.clientWidth, this.canvas.clientHeight);
+    const totalCenter = this.math.centerOfArea(this.canvas.clientWidth, this.canvas.clientHeight);
 
     const baseArea = Math.abs(this.config.width * this.config.height);
     const baseScale = Math.pow(totalArea / baseArea * this.config.scale, 0.5);
     const baseWidthScaled = baseScale * this.config.width;
     const baseHeightScaled = baseScale * this.config.height;
-    const baseCenter = this.arithmetics.centerPoint(baseWidthScaled, baseHeightScaled);
+    const baseCenter = this.math.centerOfArea(baseWidthScaled, baseHeightScaled);
 
     this.matrix = {
       start: {
@@ -189,7 +182,7 @@ export class GraphsComponent implements OnChanges, OnInit {
   }
 
   private genVectorPoint(point: Point, vector: number) {
-    const range = this.arithmetics.Δ(this.matrix.start, this.matrix.end) * this.config.vectors.range;
+    const range = this.math.Δ(this.matrix.start, this.matrix.end) * this.config.vectors.range;
 
     return {
       x: range * Math.sin(Math.PI * vector) + point.x,
@@ -215,7 +208,7 @@ export class GraphsComponent implements OnChanges, OnInit {
   private *shiftNumber(space: number, vector: number) {
     let current = 0;
     let index = 0;
-    const sign = this.flipSign();
+    const sign = this.math.flipSign();
 
     while (true) {
       yield current = sign.next().value * index * space + current;
@@ -223,14 +216,6 @@ export class GraphsComponent implements OnChanges, OnInit {
     }
   }
 
-  private *flipSign() {
-    let sign = 1;
-
-    while (true) {
-      yield sign = sign * (-1);
-    }
-  }
-
   public prepareGuillocheExport(guillocheElement) {
     if (this.genLoadedAllGraphs.next().value) {
       this.svgChange.emit(this.svgElementRef);
diff --git a/src/app/directives/guilloche.directive.ts b/src/app/directives/guilloche.directive.ts
index af9cfed..fcbf4ea 100644
--- a/src/app/directives/guilloche.directive.ts
+++ b/src/app/directives/guilloche.directive.ts
@@ -14,11 +14,13 @@
  * Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-import { ElementRef, HostListener, Output, EventEmitter, Input, Directive, OnChanges, SimpleChanges } from '@angular/core';
+import { ElementRef, HostListener, Output, EventEmitter, Input, Directive, OnChanges, OnInit, SimpleChanges } from '@angular/core';
 import * as Selection from 'd3-selection';
 import * as Shape from 'd3-shape';
 import * as Random from 'd3-random';
 import * as Drag from 'd3-drag';
+import * as Ease from 'd3-ease';
+import * as Timer from 'd3-timer';
 
 import { environment as env } from './../../environments/environment';
 import { Config } from './../models/config.model';
@@ -26,33 +28,74 @@ import { Graph } from './../models/graph.model';
 import { Point } from './../models/point.model';
 import { Param } from './../models/param.model';
 import { CanvasService } from './../services/canvas.service';
-import { ArithmeticService } from './../services/arithmetic.service';
+import { MathService } from './../services/math.service';
+import { GraphService } from '../services/graph.service';
+import { AnimationService } from './../services/animation.service';
+import { spread } from 'q';
 
 @Directive({
   selector: '[guilloche]'
 })
-export class GuillocheDirective implements OnChanges {
+export class GuillocheDirective implements OnChanges, OnInit {
 
   private canvas: any;
   private group: any;
+  private animationInterval: any;
+  private x: any;
+  private y: any;
 
   @Input() graph: Graph;
   @Input() matrix: any;
   @Input() config: any;
+  @Input() animate: boolean;
 
   @Output() guillocheChange = new EventEmitter();
 
   constructor(
     private canvasService: CanvasService,
     private el: ElementRef,
-    private arithmetics: ArithmeticService
+    private math: MathService,
+    private graphService: GraphService,
+    private animationService: AnimationService
   ) {
     this.group = Selection.select(el.nativeElement);
     this.canvas = Selection.select(this.canvasService.get);
   }
 
+  ngOnInit() {
+    // console.log('guilloche:init');
+    // Timer.timer(function(elapsed) {
+    //   let t = (elapsed % 3000) / 3000;
+    //   console.log(t);
+    //   // dot1.attr("cx", x(t)).attr("cy", y(ease(t)));
+    //   // dot2.attr("cy", y(ease(t)));
+    // });
+
+    // console.log(Ease.easeLinear(0.5));
+    // const t = Timer.timer(function(elapsed) {
+    //   if (elapsed > 200) {
+    //     t.stop();
+    //   }
+    // }, 1000);
+  }
+
   ngOnChanges(changes: SimpleChanges) {
-    // console.log(this.graph);
+    // @todo modify graph here instead of in graphs.component.ts
+    this.group.selectAll('*').remove();
+
+    // console.log('guilloche:changes', changes);
+
+    if (this.graphService.isAnimated) {
+      console.log('is animated');
+      // this.graphService.startAnimation();
+      this.animationInterval = setInterval(() => this.animateGraph(), 60);
+    } else {
+      if (this.animationInterval) {
+        console.log('not animated');
+        // this.graphService.stopAnimation();
+        clearInterval(this.animationInterval);
+      }
+    }
 
     const points = [
       this.graph.start.point,
@@ -63,6 +106,18 @@ export class GuillocheDirective implements OnChanges {
     this.guillocheChanged();
   }
 
+  private animateGraph() {
+    this.group.selectAll('*').remove();
+    this.graph = this.animationService.animate(this.graph);
+    // this.saveGraph();
+    const points = [
+      this.graph.start.point,
+      ...this.graph.nodes,
+      this.graph.end.point
+    ];
+    this.spreadLines(points);
+  }
+
   public guillocheChanged() {
     this.guillocheChange.emit(this.el.nativeElement);
   }
@@ -77,50 +132,93 @@ export class GuillocheDirective implements OnChanges {
       .attr('stroke-width', this.graph.stroke)
       .attr('fill', 'none');
 
-    if (!env.production) {
+    if (env.grid) {
       this.showGrid();
     }
   }
 
   private spreadLines(points: Point[]) {
-    const indexMiddle = Math.floor(points.length * 0.5);
-    const pointMiddle = points[indexMiddle];
-    const closestCenter = this.arithmetics.getClosestCenter(pointMiddle, this.matrix);
-    const radius = this.arithmetics.Δ(pointMiddle, closestCenter);
-    const spreadPoints = [];
-    const pies = 80;
+    const shiftedMedians = [];
+    const medianPoint = this.math.centerOfCurve(points);
+    const medianIndex = this.math.medianIndex(points);
+    const genshiftedMedians = this.graphService.spreadOrthogonal(medianPoint, 20);
 
-    for (let i = 0; i < pies; i++) {
-      spreadPoints.push({
-        x: radius * Math.cos(2 * i * Math.PI / pies) + closestCenter.x,
-        y: radius * Math.sin(2 * i * Math.PI / pies) + closestCenter.y,
+    for (let i = 0; i < this.config.spread; i++) {
+      shiftedMedians.push(genshiftedMedians.next().value);
+    }
+
+    // const indexMiddle = Math.floor(points.length * 0.5);
+    // const pointMiddle = points[indexMiddle];
+    // const closestCenter = this.math.getClosestCenter(pointMiddle, this.matrix);
+    // const radius = this.math.Δ(pointMiddle, closestCenter);
+    // const shiftedMedians = [];
+    // const pies = 200;
+
+    // for (let i = 0; i < pies; i++) {
+      //   shiftedMedians.push({
+        //     x: radius * Math.cos(2 * i * Math.PI / pies) + closestCenter.x,
+        //     y: radius * Math.sin(2 * i * Math.PI / pies) + closestCenter.y,
+        //   });
+        // }
+
+        // shiftedMedians.sort((a, b) => {
+          //   // Good possibility to align orientation points outsite
+          //   return this.math.Δ(b, pointMiddle) - this.math.Δ(a, pointMiddle);
+          // });
+
+          // console.log(shiftedMedians);
+
+          // shiftedMedians.some((point, index) => {
+            //   points[indexMiddle] = point;
+
+            //   this.drawGraph(points);
+
+            //   return index === this.config.spread - 1;
+            // });
+    if (env.grid) {
+      [medianPoint, ...shiftedMedians].forEach((point, index) => {
+        this.group.append('circle')
+          .attr('cx', point.x)
+          .attr('cy', point.y)
+          .attr('r', 10 / index)
+          .attr('fill-opacity', 0.6)
+          .attr('fill', 'darkgray');
       });
     }
 
-    spreadPoints.sort((a, b) => {
-      // Good possibility to align orientation points outsite
-      return this.arithmetics.Δ(b, pointMiddle) - this.arithmetics.Δ(a, pointMiddle);
-    });
-
-    spreadPoints.some((point, index) => {
-      points[indexMiddle] = point;
-
-      this.drawGraph(points);
-
-      return index === this.config.spread - 1;
+    shiftedMedians.forEach(median => {
+      const shiftedGraph = points.slice();
+      shiftedGraph.splice(medianIndex, 1, median);
+      this.drawGraph(shiftedGraph);
     });
 
+    // this.drawGraph(points);
   }
 
+  // private animateRange(n: number) {
+  //   return Ease.scaleLinear().range([n, n + 100]);
+  // }
+
   private showGrid() {
-    this.graph.nodes.forEach(point => {
-      this.group.append('circle')
+    this.graph.nodes.forEach((point, index) => {
+      const circle = this.group.append('g');
+      // const xRange = this.animateRange(point.x);
+      // const yRange = this.animateRange(point.y);
+
+      circle.append('circle')
         .attr('cx', point.x)
         .attr('cy', point.y)
         .attr('r', 3)
-        .attr('stroke-width', 0.1)
-        .attr('fill-opacity', 0)
-        .attr('stroke', 'darkgray');
+        .attr('fill-opacity', 0.6)
+        .attr('fill', this.graph.color);
+
+      circle.append('text')
+        .attr('x', point.x)
+        .attr('y', point.y)
+        .attr('dx', 8)
+        .attr('dy', 15)
+        .attr('fill', this.graph.color)
+        .text(index);
     });
   }
 }
diff --git a/src/app/models/point.model.ts b/src/app/models/point.model.ts
index aff2e70..f1103e6 100644
--- a/src/app/models/point.model.ts
+++ b/src/app/models/point.model.ts
@@ -18,4 +18,5 @@ export interface Point {
   x: number;
   y: number;
   color?: string;
+  ascent?: number;
 }
diff --git a/src/app/services/animation.service.ts b/src/app/services/animation.service.ts
index 2f37612..4251f39 100644
--- a/src/app/services/animation.service.ts
+++ b/src/app/services/animation.service.ts
@@ -19,7 +19,7 @@ import { interval, Observable } from 'rxjs';
 import * as Selection from 'd3-selection';
 
 import { Graph } from '../models/graph.model';
-import { ArithmeticService } from './arithmetic.service';
+import { MathService } from './math.service';
 import { HistoryService } from './history.service';
 
 @Injectable()
@@ -33,27 +33,28 @@ export class AnimationService {
   // private subscribtion: any;
 
   constructor(
-    private arithmetics: ArithmeticService,
+    private math: MathService,
     private historyService: HistoryService,
   ) {
   }
 
-  public animate(initialGraphs: Graph[]) {
-    const newGraphs = initialGraphs.slice();
+  // public animate(initialGraphs: Graph[]) {
+  public animate(initialGraph: Graph) {
+    // const newGraphs = initialGraphs.slice();
 
-    return newGraphs.map(graph => {
+    // return newGraphs.map(graph => {
 
-      const newGraph = Object.assign({}, graph);
+      const newGraph = Object.assign({}, initialGraph);
       const indexMiddle = Math.floor(newGraph.nodes.length * 0.5);
       const pointMiddle = newGraph.nodes[indexMiddle];
 
       newGraph.nodes.splice(indexMiddle, 1, {
-        x: pointMiddle.x - 1,
-        y: pointMiddle.y + 1,
+        x: pointMiddle.x - 2,
+        y: pointMiddle.y + 2,
       });
 
       return newGraph;
-    });
+  //   });
   }
 }
 
diff --git a/src/app/services/graph.service.ts b/src/app/services/graph.service.ts
new file mode 100644
index 0000000..c053a64
--- /dev/null
+++ b/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
+    };
+  }
+}
diff --git a/src/app/services/arithmetic.service.ts b/src/app/services/math.service.ts
similarity index 63%
rename from src/app/services/arithmetic.service.ts
rename to src/app/services/math.service.ts
index f79ff79..aa5cde9 100644
--- a/src/app/services/arithmetic.service.ts
+++ b/src/app/services/math.service.ts
@@ -19,9 +19,10 @@ import * as Selection from 'd3-selection';
 import * as Random from 'd3-random';
 
 import { Point } from './../models/point.model';
+import { Graph } from './../models/graph.model';
 
 @Injectable()
-export class ArithmeticService {
+export class MathService {
 
   /**
    * Calculate distance between to points with coordinates.
@@ -64,10 +65,58 @@ export class ArithmeticService {
     };
   }
 
-  public centerPoint(width, height): Point {
+  public centerOfArea(width, height): Point {
     return {
       x: width * 0.5,
       y: height * 0.5
     };
   }
+
+  public centerOfPoints(p1: Point, p2: Point) {
+    return {
+      x: (p1.x + p2.x) * 0.5,
+      y: (p1.y + p2.y) * 0.5
+    };
+  }
+
+  public centerOfCurve(curve: Point[]) {
+    const genMedian = this.medianPoint(curve);
+    const p1 = genMedian.next().value;
+    const p2 = genMedian.next().value;
+    const radians = this.angleRadians(p1, p2);
+
+    return Object.assign(this.centerOfPoints(p1, p2), { ascent: radians });
+  }
+
+  public angleRadians(p1: Point, p2: Point) {
+    return Math.atan2(p2.y - p1.y, p2.x - p1.x);
+  }
+
+  public angleDegree(p1: Point, p2: Point) {
+    return this.angleRadians(p1, p2) * 180 / Math.PI;
+  }
+
+  public medianIndex(list: any): number {
+    return Math.floor(list.length * 0.5);
+  }
+
+  public *medianPoint(points: Point[]) {
+    let index: number;
+    const list: Point[] = points.slice();
+
+    while (list) {
+      index = this.medianIndex(points);
+      yield list[index];
+
+      list.splice(index, 1);
+    }
+  }
+
+  public *flipSign() {
+    let sign = 1;
+
+    while (true) {
+      yield sign = sign * (-1);
+    }
+  }
 }
diff --git a/src/environments/environment.ts b/src/environments/environment.ts
index a71c77f..4a6a2ec 100644
--- a/src/environments/environment.ts
+++ b/src/environments/environment.ts
@@ -16,6 +16,7 @@
 
 export const environment = {
   production: false,
+  grid: false,
   guilloche: {
     colors: {
       primary: '#cb0c4d',
@@ -30,11 +31,11 @@ export const environment = {
     vectors: {
       start: 1,
       end: 0,
-      range: 0.4,
+      range: 0.4
     },
     nodes: 4,
     stroke: 1,
     spread: 12,
-    space: 5
+    space: 10
   }
 };