From b6fd86599343e07688302e7c2d2b890fdbfb1244 Mon Sep 17 00:00:00 2001
From: Michael Herzog <michael.herzog@human-interactive.org>
Date: Tue, 24 Jun 2025 09:38:22 +0200
Subject: [PATCH] Renderers: Initial support for `Float16Array`. (#31305)

---
 .eslintrc.json                                            | 3 ++-
 examples/webgl_geometry_colors.html                       | 3 ++-
 src/core/BufferAttribute.js                               | 4 ++--
 src/renderers/webgl-fallback/utils/WebGLAttributeUtils.js | 4 ++++
 src/renderers/webgl/WebGLAttributes.js                    | 4 ++++
 src/renderers/webgpu/utils/WebGPUAttributeUtils.js        | 6 ++++++
 6 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/.eslintrc.json b/.eslintrc.json
index b4089e0aa9eb07..bdb1813613c210 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -42,7 +42,8 @@
     "esprima": "readonly",
     "jsonlint": "readonly",
     "VideoFrame": "readonly",
-    "VideoDecoder": "readonly"
+    "VideoDecoder": "readonly",
+    "Float16Array": "readonly"
   },
   "rules": {
     "no-throw-literal": [
diff --git a/examples/webgl_geometry_colors.html b/examples/webgl_geometry_colors.html
index c916370e675d07..4c7880c47e3e05 100644
--- a/examples/webgl_geometry_colors.html
+++ b/examples/webgl_geometry_colors.html
@@ -103,7 +103,8 @@
 				const geometry1 = new THREE.IcosahedronGeometry( radius, 1 );
 
 				const count = geometry1.attributes.position.count;
-				geometry1.setAttribute( 'color', new THREE.BufferAttribute( new Float32Array( count * 3 ), 3 ) );
+				const arrayType = ( typeof Float16Array !== 'undefined' ) ? Float16Array : Float32Array;
+				geometry1.setAttribute( 'color', new THREE.BufferAttribute( new arrayType( count * 3 ), 3 ) );
 
 				const geometry2 = geometry1.clone();
 				const geometry3 = geometry1.clone();
diff --git a/src/core/BufferAttribute.js b/src/core/BufferAttribute.js
index 07fd3dc5c15108..3e1b10fe68f3f5 100644
--- a/src/core/BufferAttribute.js
+++ b/src/core/BufferAttribute.js
@@ -841,8 +841,8 @@ class Uint32BufferAttribute extends BufferAttribute {
  * Convenient class that can be used when creating a `Float16` buffer attribute with
  * a plain `Array` instance.
  *
- * This class automatically converts to and from FP16 since `Float16Array` is not
- * natively supported in JavaScript.
+ * This class automatically converts to and from FP16 via `Uint16Array` since `Float16Array`
+ * browser support is still problematic.
  *
  * @augments BufferAttribute
  */
diff --git a/src/renderers/webgl-fallback/utils/WebGLAttributeUtils.js b/src/renderers/webgl-fallback/utils/WebGLAttributeUtils.js
index 4082a9d5aefb44..2b4453fba77c93 100644
--- a/src/renderers/webgl-fallback/utils/WebGLAttributeUtils.js
+++ b/src/renderers/webgl-fallback/utils/WebGLAttributeUtils.js
@@ -114,6 +114,10 @@ class WebGLAttributeUtils {
 
 			type = gl.FLOAT;
 
+		} else if ( typeof Float16Array !== 'undefined' && array instanceof Float16Array ) {
+
+			type = gl.HALF_FLOAT;
+
 		} else if ( array instanceof Uint16Array ) {
 
 			if ( attribute.isFloat16BufferAttribute ) {
diff --git a/src/renderers/webgl/WebGLAttributes.js b/src/renderers/webgl/WebGLAttributes.js
index bb530218266c46..c022775224d9fa 100644
--- a/src/renderers/webgl/WebGLAttributes.js
+++ b/src/renderers/webgl/WebGLAttributes.js
@@ -21,6 +21,10 @@ function WebGLAttributes( gl ) {
 
 			type = gl.FLOAT;
 
+		} else if ( typeof Float16Array !== 'undefined' && array instanceof Float16Array ) {
+
+			type = gl.HALF_FLOAT;
+
 		} else if ( array instanceof Uint16Array ) {
 
 			if ( attribute.isFloat16BufferAttribute ) {
diff --git a/src/renderers/webgpu/utils/WebGPUAttributeUtils.js b/src/renderers/webgpu/utils/WebGPUAttributeUtils.js
index be81c0c33fe1ba..32799497b33814 100644
--- a/src/renderers/webgpu/utils/WebGPUAttributeUtils.js
+++ b/src/renderers/webgpu/utils/WebGPUAttributeUtils.js
@@ -12,6 +12,12 @@ const typedArraysToVertexFormatPrefix = new Map( [
 	[ Float32Array, [ 'float32', ]],
 ] );
 
+if ( typeof Float16Array !== 'undefined' ) {
+
+	typedArraysToVertexFormatPrefix.set( Float16Array, [ 'float16' ] );
+
+}
+
 const typedAttributeToVertexFormatPrefix = new Map( [
 	[ Float16BufferAttribute, [ 'float16', ]],
 ] );