IParticleSystem: add doNotSerialize (#17342)

This commit adds an optional doNotSerialize to IParticleSystem, makes it
possible to control if a particle system should be serialized.
The `doNotSerialize` is also added to `ParticleSystem` and
`GPUParticleSystem`, but not added to `SubEmitter`,
`SubEmitter.particleSystem.doNotSerialize` is checked instead.

Author: kzhsw

packages/dev/core/src/Misc/sceneSerializer.ts

@@ -338,7 +338,10 @@ export class SceneSerializer {
         // Particles Systems
         serializationObject.particleSystems = [];
         for (index = 0; index < scene.particleSystems.length; index++) {
-            serializationObject.particleSystems.push(scene.particleSystems[index].serialize(false));
+            const particleSystem = scene.particleSystems[index];
+            if (!particleSystem.doNotSerialize) {
+                serializationObject.particleSystems.push(particleSystem.serialize(false));
+            }
         }
 
         // Post processes

packages/dev/core/src/Particles/IParticleSystem.ts

@@ -299,6 +299,11 @@ export interface IParticleSystem {
      */
     isNodeGenerated: boolean;
 
+    /**
+     * Specifies if the particle system should be serialized
+     */
+    doNotSerialize?: boolean;
+
     /**
      * Gets the maximum number of particles active at the same time.
      * @returns The max number of active particles.

packages/dev/core/src/Particles/gpuParticleSystem.ts

@@ -109,6 +109,11 @@ export class GPUParticleSystem extends BaseParticleSystem implements IDisposable
     private _platform: IGPUParticleSystemPlatform;
     private _rebuildingAfterContextLost = false;
 
+    /**
+     * Specifies if the particle system should be serialized
+     */
+    public doNotSerialize = false;
+
     /**
      * Gets a boolean indicating if the GPU particles can be rendered on current browser
      */

packages/dev/core/src/Particles/particleSystem.ts

@@ -82,6 +82,12 @@ export class ParticleSystem extends ThinParticleSystem {
      * The current active Sub-systems, this property is used by the root particle system only.
      */
     public activeSubSystems: Array<ParticleSystem>;
+
+    /**
+     * Specifies if the particle system should be serialized
+     */
+    public doNotSerialize = false;
+
     /**
      * Creates a Point Emitter for the particle system (emits directly from the emitter position)
      * @param direction1 Particles are emitted between the direction1 and direction2 from within the box
@@ -878,7 +884,9 @@ export class ParticleSystem extends ThinParticleSystem {
             for (const subs of this._subEmitters) {
                 const cell = [];
                 for (const sub of subs) {
-                    cell.push(sub.serialize(serializeTexture));
+                    if (!sub.particleSystem.doNotSerialize) {
+                        cell.push(sub.serialize(serializeTexture));
+                    }
                 }
 
                 serializationObject.subEmitters.push(cell);

packages/dev/core/src/Particles/particleSystemSet.ts

@@ -137,7 +137,9 @@ export class ParticleSystemSet implements IDisposable {
 
         result.systems = [];
         for (const system of this.systems) {
-            result.systems.push(system.serialize(serializeTexture));
+            if (!system.doNotSerialize) {
+                result.systems.push(system.serialize(serializeTexture));
+            }
         }
 
         if (this._emitterNode) {