TSL instancePositionNode

src/materials/nodes/NodeMaterial.js

@@ -265,6 +265,17 @@ class NodeMaterial extends Material {
 		 */
 		this.positionNode = null;
 
+		/**
+		 * Allows to overwrite {@link positionLocal} immediately after it has
+		 * been transformed by the instance matrix in the vertex shader.
+		 * Note: this node property only has an effect when used with
+		 * an {@link InstancedMesh} or a {@link BatchedMesh}.
+		 *
+		 * @type {?Node<vec3>}
+		 * @default null
+		 */
+		this.instancePositionNode = null;
+
 		/**
 		 * This node property is intended for logic which modifies geometry data once or per animation step.
 		 * Apps usually place such logic randomly in initialization routines or in the animation loop.

src/nodes/accessors/BatchNode.js

@@ -7,6 +7,7 @@ import { textureSize } from './TextureSizeNode.js';
 import { tangentLocal } from './Tangent.js';
 import { instanceIndex, drawIndex } from '../core/IndexNode.js';
 import { varyingProperty } from '../core/PropertyNode.js';
+import NodeMaterial from '../../materials/nodes/NodeMaterial.js';
 
 /**
  * This node implements the vertex shader logic which is required
@@ -134,6 +135,12 @@ class BatchNode extends Node {
 
 		positionLocal.assign( batchingMatrix.mul( positionLocal ) );
 
+		if ( builder.material instanceof NodeMaterial && builder.material.instancePositionNode != null ) {
+
+			positionLocal.assign( builder.material.instancePositionNode );
+
+		}
+
 		const transformedNormal = normalLocal.div( vec3( bm[ 0 ].dot( bm[ 0 ] ), bm[ 1 ].dot( bm[ 1 ] ), bm[ 2 ].dot( bm[ 2 ] ) ) );
 
 		const batchingNormal = bm.mul( transformedNormal ).xyz;

src/nodes/accessors/InstanceNode.js

@@ -12,6 +12,7 @@ import { instanceIndex } from '../core/IndexNode.js';
 import { InstancedInterleavedBuffer } from '../../core/InstancedInterleavedBuffer.js';
 import { InstancedBufferAttribute } from '../../core/InstancedBufferAttribute.js';
 import { DynamicDrawUsage } from '../../constants.js';
+import NodeMaterial from '../../materials/nodes/NodeMaterial.js';
 
 /**
  * This node implements the vertex shader logic which is required
@@ -187,6 +188,12 @@ class InstanceNode extends Node {
 		const instancePosition = instanceMatrixNode.mul( positionLocal ).xyz;
 		positionLocal.assign( instancePosition );
 
+		if ( builder.material instanceof NodeMaterial && builder.material.instancePositionNode != null ) {
+
+			positionLocal.assign( builder.material.instancePositionNode );
+
+		}
+
 		if ( builder.needsPreviousData() ) {
 
 			positionPrevious.assign( this.getPreviousInstancedPosition( builder ) );