新しい点電荷を追加

app/index.html

@@ -24,6 +24,12 @@
             <img class="control_img" src="./static/point_charge.png" alt="点">
           </button>
         </div>
+        <div class="control_button">
+          <p class="title">新しい点</p>
+          <button type="button" id="add_new_point_charge_button">
+            <img class="control_img" src="./static/point_charge.png" alt="点">
+          </button>
+        </div>
         <div class="control_button">
           <p class="title">無限線</p>
           <button type="button" id="add_infinity_line_charge_button">

app/script/main.ts

@@ -12,6 +12,7 @@ import { SphereSurfaceCharge } from './sphereSurfaceCharge';
 import { SphereVolumeCharge } from './sphereVolumeCharge';
 import { InfinityCylinderVolumeCharge } from './infinityCylinderVolumeCharge';
 import { InfinityCylinderSurfaceCharge } from './infinityCylinderSurfaceCharge';
+import { NewPointCharge } from './newPointCharge';
 import { Store } from './store';
 
 const start = () => {
@@ -157,6 +158,11 @@ const start = () => {
         addCharge(new PointCharge(new THREE.Vector3(), 10));
     });
 
+    // 新しい点電荷追加
+    document.getElementById('add_new_point_charge_button')!.addEventListener('click', () => {
+        addCharge(new NewPointCharge(new THREE.Vector3(), 10));
+    });
+
     // 線電荷追加
     document.getElementById('add_infinity_line_charge_button')!.addEventListener('click', () => {
         addCharge(new InfinityLineCharge(new THREE.Vector3(), new THREE.Euler(), 0.1));

app/script/newPointCharge.ts

@@ -0,0 +1,202 @@
+import * as THREE from 'three';
+import { Charge, ChargeType, ChargeToChargeType } from './charge';
+import { kCoulomb } from './constants';
+import { GSS } from './gss';
+import { Editor, PositionEditor, NumberEditor } from './editor';
+import { Store } from './store';
+
+
+
+/**
+ * 点電荷
+ */
+export class NewPointCharge extends Charge {
+
+
+    private charge: number;
+
+
+    /**
+     * 点電荷を構築する
+     * @param position 点電荷の座標
+     * @param charge 電荷量
+     */
+    constructor(position: THREE.Vector3, charge: number) {
+
+        const geometry = NewPointCharge.pointChargeGeometry;
+        const material = NewPointCharge.getMaterial(charge);
+        super(geometry, material);
+
+        this.position.copy(position);
+
+        this.charge = charge;
+
+    }
+
+
+    /**
+     * 電荷の正負を取得する
+     * @returns 電荷の正負
+     */
+    override getChargeType = (): ChargeType => {
+
+        return ChargeToChargeType(this.charge);
+
+    }
+
+
+    /**
+     * 任意の座標における電荷との距離ベクトルを取得する
+     * @param position 任意の座標
+     * @returns 電荷との距離ベクトル
+     */
+    private distanceFrom = (position: THREE.Vector3): THREE.Vector3 => {
+
+        return position.clone().sub(this.position);
+
+    }
+
+
+    /**
+     * 任意の座標が電荷に接触しているかどうかを判定する
+     * @param position 任意の座標
+     * @param threshold 閾値
+     * @returns 接触しているかどうか
+     */
+    override isContact = (position: THREE.Vector3, threshold: number): boolean => {
+
+        return this.position.distanceToSquared(position) < threshold ** 2;
+
+    }
+
+
+    /**
+     * 任意の座標における、この電荷からの電界ベクトルを返す
+     * @param position 任意の座標
+     * @returns 電界ベクトル
+     */
+    override electricFieldVector = (position: THREE.Vector3): THREE.Vector3 => {
+
+        const diffVector = this.distanceFrom(position);
+
+        if (diffVector.lengthSq() < Number.EPSILON) {
+            return new THREE.Vector3();  // 観測点が点電荷と重なっている場合 (0除算防止)
+        }
+
+        // E=kq/r^3
+        return diffVector.multiplyScalar((kCoulomb * this.charge) / (diffVector.length() ** 3));
+
+    }
+
+
+    /**
+     * 電気力線の始点、方向ベクトルの配列を返す
+     * @returns 電気力線の始点、方向ベクトルの配列
+     */
+    override electricForceLinesDirection = (): { begin: THREE.Vector3, direction: THREE.Vector3 }[] => {
+
+        return GSS(25).map((vector) => { return { begin: this.position, direction: vector } });
+
+    }
+
+
+    /**
+     * 解放
+     * @note ジオメトリの破棄等を行う
+     */
+    override dispose = () => { }
+
+
+    /**
+     * JSON フォーマット
+     * {
+     *     position: [number, number, number],
+     *     charge: number
+     * }
+     */
+
+
+    /**
+     * JSONから電荷を生成する
+     */
+    static override fromJSON = (json: any): Charge => {
+
+        return new NewPointCharge(
+            new THREE.Vector3(json.position.x, json.position.y, json.position.z),
+            json.charge
+        );
+
+    }
+
+
+    /**
+     * 電荷をJSONに変換する
+     */
+    override toJSON = (): any => {
+
+        return {
+            position: {
+                x: this.position.x,
+                y: this.position.y,
+                z: this.position.z
+            },
+            charge: this.charge
+        };
+
+    }
+
+
+    /**
+     * パラメーター設定用エディタを生成する
+     */
+    override createEditor = (): Editor => {
+
+        const positionEditor = new PositionEditor({
+            position: this.position,
+            onChange: (value: THREE.Vector3) => {
+                this.position.copy(value);
+            }
+        });
+
+        const chargeEditor = new NumberEditor({
+            name: "電荷量[C]",
+            value: this.charge,
+            onChange: (value: number) => {
+                this.charge = value;
+                this.material = NewPointCharge.getMaterial(this.charge);
+            }
+        });
+
+        return new Editor()
+            .add(positionEditor)
+            .add(chargeEditor)
+            ;
+
+    }
+
+
+    private static readonly plusMaterial = new THREE.MeshBasicMaterial({ color: 0xff0000 });
+    private static readonly minusMaterial = new THREE.MeshBasicMaterial({ color: 0x0000ff });
+    private static readonly neutralMaterial = new THREE.MeshBasicMaterial({ color: 0xffff00 });
+    private static readonly pointChargeGeometry = new THREE.SphereGeometry(4, 32, 32);
+
+    /**
+     * 電荷量からマテリアルを取得する
+     * @param charge 電荷量
+     * @returns マテリアル
+    */
+    private static getMaterial = (charge: number) => {
+
+        if (charge > 0)
+            return NewPointCharge.plusMaterial;
+        else if (charge < 0)
+            return NewPointCharge.minusMaterial;
+        else
+            return NewPointCharge.neutralMaterial;
+
+    }
+
+
+}
+
+Store.RegisterChargeGenerator("NewPointCharge", NewPointCharge.fromJSON);