Merge pull request #7810 from jsdream/collisions

Add an option to optimize collision detection performance.

dist/preview release/what's new.md

@@ -46,6 +46,9 @@
 ### WebXR
 - Added optional ray and mesh selection predicates to `WebXRControllerPointerSelection` ([Exolun](https://github.com/Exolun))
 
+### Collisions
+- Added an option to optimize collision detection performance ([jsdream](https://github.com/jsdream)) - [PR](https://github.com/BabylonJS/Babylon.js/pull/7810)
+
 ## Bugs
 
 - Fix infinite loop in `GlowLayer.unReferenceMeshFromUsingItsOwnMaterial` ([Popov72](https://github.com/Popov72)

src/Collisions/collisionCoordinator.ts

@@ -57,9 +57,12 @@ export class DefaultCollisionCoordinator implements ICollisionCoordinator {
 
         collider._initialize(position, velocity, closeDistance);
 
-        // Check all meshes
-        for (var index = 0; index < this._scene.meshes.length; index++) {
-            var mesh = this._scene.meshes[index];
+        // Check if collision detection should happen against specified list of meshes or,
+        // if not specified, against all meshes in the scene
+        var meshes = (excludedMesh && excludedMesh.surroundingMeshes) || this._scene.meshes;
+
+        for (var index = 0; index < meshes.length; index++) {
+            var mesh = meshes[index];
             if (mesh.isEnabled() && mesh.checkCollisions && mesh.subMeshes && mesh !== excludedMesh && ((collisionMask & mesh.collisionGroup) !== 0)) {
                 mesh._checkCollision(collider);
             }

src/Collisions/meshCollisionData.ts

@@ -12,6 +12,7 @@ export class _MeshCollisionData {
     public _checkCollisions = false;
     public _collisionMask = -1;
     public _collisionGroup = -1;
+    public _surroundingMeshes: Nullable<AbstractMesh[]> = null;
     public _collider: Nullable<Collider> = null;
     public _oldPositionForCollisions = new Vector3(0, 0, 0);
     public _diffPositionForCollisions = new Vector3(0, 0, 0);

src/Meshes/abstractMesh.ts

@@ -559,6 +559,23 @@ export class AbstractMesh extends TransformNode implements IDisposable, ICullabl
         this._meshCollisionData._collisionGroup = !isNaN(mask) ? mask : -1;
     }
 
+    /**
+     * Gets or sets current surrounding meshes (null by default).
+     *
+     * By default collision detection is tested against every mesh in the scene.
+     * It is possible to set surroundingMeshes to a defined list of meshes and then only these specified
+     * meshes will be tested for the collision.
+     *
+     * Note: if set to an empty array no collision will happen when this mesh is moved.
+     */
+    public get surroundingMeshes(): Nullable<AbstractMesh[]> {
+        return this._meshCollisionData._surroundingMeshes;
+    }
+
+    public set surroundingMeshes(meshes: Nullable<AbstractMesh[]>) {
+        this._meshCollisionData._surroundingMeshes = meshes;
+    }
+
     // Edges
     /**
      * Defines edge width used when edgesRenderer is enabled