From 2614bff28c0ca995fa4c24735e95331333ef6626 Mon Sep 17 00:00:00 2001
From: Christian Helgeson <62450112+cmhhelgeson@users.noreply.github.com>
Date: Wed, 1 Oct 2025 15:47:05 -0700
Subject: [PATCH 1/2] add polyfill for GLSLNodeBuilder

---
 .../webgl-fallback/nodes/GLSLNodeBuilder.js   | 36 +++++++++++++++++--
 1 file changed, 34 insertions(+), 2 deletions(-)

diff --git a/src/renderers/webgl-fallback/nodes/GLSLNodeBuilder.js b/src/renderers/webgl-fallback/nodes/GLSLNodeBuilder.js
index 7728c0bf741162..a106f5a7f10f45 100644
--- a/src/renderers/webgl-fallback/nodes/GLSLNodeBuilder.js
+++ b/src/renderers/webgl-fallback/nodes/GLSLNodeBuilder.js
@@ -1,4 +1,4 @@
-import { GLSLNodeParser, NodeBuilder, TextureNode, vectorComponents } from '../../../nodes/Nodes.js';
+import { GLSLNodeParser, NodeBuilder, TextureNode, vectorComponents, CodeNode } from '../../../nodes/Nodes.js';
 
 import NodeUniformBuffer from '../../common/nodes/NodeUniformBuffer.js';
 import NodeUniformsGroup from '../../common/nodes/NodeUniformsGroup.js';
@@ -9,6 +9,11 @@ import { NoColorSpace, ByteType, ShortType, RGBAIntegerFormat, RGBIntegerFormat,
 import { DataTexture } from '../../../textures/DataTexture.js';
 import { error } from '../../../utils.js';
 
+const glslPolyfills = {
+	bitcast_int_uint: new CodeNode( /* glsl */'uint tsl_bitcast_uint_to_int ( int x ) { return floatBitsToInt( uintBitsToFloat( x ) ); }' ),
+	bitcast_uint_int: new CodeNode( /* glsl */'uint tsl_bitcast_int_to_uint ( int x ) { return floatBitsToUint( intBitsToFloat ( x ) ); }' )
+};
+
 const glslMethods = {
 	textureDimensions: 'textureSize',
 	equals: 'equal',
@@ -16,6 +21,8 @@ const glslMethods = {
 	bitcast_int_float: 'intBitsToFloat',
 	bitcast_uint_float: 'uintBitsToFloat',
 	bitcast_float_uint: 'floatBitsToUint',
+	bitcast_uint_int: 'tsl_bitcast_uint_to_int',
+	bitcast_int_uint: 'tsl_bitcast_int_to_uint'
 };
 
 const precisionLib = {
@@ -127,6 +134,25 @@ class GLSLNodeBuilder extends NodeBuilder {
 
 	}
 
+	/**
+	 * Includes the given method name into the current
+	 * function node.
+	 *
+	 * @private
+	 * @param {string} name - The method name to include.
+	 * @return {CodeNode} The respective code node.
+	 */
+	_include( name ) {
+
+		const codeNode = glslPolyfills[ name ];
+		codeNode.build( this );
+
+		this.addInclude( codeNode );
+
+		return codeNode;
+
+	}
+
 	/**
 	 * Returns the native shader method name for a given generic name.
 	 *
@@ -135,6 +161,12 @@ class GLSLNodeBuilder extends NodeBuilder {
 	 */
 	getMethod( method ) {
 
+		if ( glslPolyfills[ method ] !== undefined ) {
+
+			this._include( method );
+
+		}
+
 		return glslMethods[ method ] || method;
 
 	}
@@ -148,7 +180,7 @@ class GLSLNodeBuilder extends NodeBuilder {
 	 */
 	getBitcastMethod( type, inputType ) {
 
-		return glslMethods[ `bitcast_${ inputType }_${ type }` ];
+		return this.getMethod( `bitcast_${ inputType }_${ type }` );
 
 	}
 

From 3e35cdf90ba1e8f93c48a96f4fd561e5d60c389e Mon Sep 17 00:00:00 2001
From: Christian Helgeson <62450112+cmhhelgeson@users.noreply.github.com>
Date: Wed, 1 Oct 2025 15:52:56 -0700
Subject: [PATCH 2/2] unify how GLSL _include and WGSL _include work

---
 src/renderers/webgpu/nodes/WGSLNodeBuilder.js | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/src/renderers/webgpu/nodes/WGSLNodeBuilder.js b/src/renderers/webgpu/nodes/WGSLNodeBuilder.js
index cb7f1053376b09..b24000d1cbd4b2 100644
--- a/src/renderers/webgpu/nodes/WGSLNodeBuilder.js
+++ b/src/renderers/webgpu/nodes/WGSLNodeBuilder.js
@@ -2068,11 +2068,7 @@ ${ flowData.code }
 		const codeNode = wgslPolyfill[ name ];
 		codeNode.build( this );
 
-		if ( this.currentFunctionNode !== null ) {
-
-			this.currentFunctionNode.includes.push( codeNode );
-
-		}
+		this.addInclude( codeNode );
 
 		return codeNode;