Corrected trajectories in energy

js/client/utils/shapes/energy-line.js

@@ -151,13 +151,18 @@ class EnergyLine extends TrajectoryLine {
 
             // Calculate length of the segment. Applies the scale.
             let length = this._end.clone().sub(this._start).length() * this.getEnergyScale();
-
+            
             // Create a line segment for the line.
-            let segment = new LineSegment(new THREE.Vector3(0, 0, 0), new THREE.Vector3(0, 0, length), 0.5 / scale, this._lineMaterial);
-            this._line = segment;
+            if (length > 0) {
+                // It is necessary not to draw line with length 0 because the underlying cylinder has a default length 1.
+                this._line = new LineSegment(new THREE.Vector3(0, 0, 0), new THREE.Vector3(0, 0, length), 0.5 / scale, this._lineMaterial);
 
-            // Add the line to the data group.
-            this._dataGroup.add(this._line.object3D);
+                // Add the line to the data group.
+                this._dataGroup.add(this._line.object3D);
+            }
+            else {
+                this._line = null;
+            }
         }
 
         // Update the data.
@@ -189,6 +194,7 @@ class EnergyLine extends TrajectoryLine {
             this._line.object3D.visible = visibility;
         }
         this._dataGroup.visible = visibility;
+        this._pointSphereGroup.visible = visibility;
     }
 
     /**

js/client/views/3D/reciprocal/trajectory-view.js

@@ -104,12 +104,8 @@ class TrajectoryView3D extends View3D {
 
                 this._energyLine.start = energyStart;
                 this._energyLine.end = energyStart;
-
-                // Show energy line for ki and kf trajectories.
-                if (this._type === 'ki' || this._type === 'kf') {
-                    this._energyLine.setVisibility(true);
-                }
-
+                this._energyLine.setVisibility(true);
+                
                 this._drawLines = true;
             }
             else {