TSL: Add `texture3DLoad` and `texture3DLevel` (#32171)

* Examples: Fix compute_texture_pingpong example

* TSL: Add texture3DLoad and texture3DLevel

src/nodes/accessors/Texture3DNode.js

@@ -192,8 +192,33 @@ export default Texture3DNode;
  * @tsl
  * @function
  * @param {Data3DTexture} value - The 3D texture.
- * @param {?Node<vec2|vec3>} [uvNode=null] - The uv node.
+ * @param {?Node<vec3>} [uvNode=null] - The uv node.
  * @param {?Node<int>} [levelNode=null] - The level node.
  * @returns {Texture3DNode}
  */
 export const texture3D = /*@__PURE__*/ nodeProxy( Texture3DNode ).setParameterLength( 1, 3 );
+
+/**
+ * TSL function for creating a texture node that fetches/loads texels without interpolation.
+ *
+ * @tsl
+ * @function
+ * @param {?(Texture|TextureNode)} [value=EmptyTexture] - The texture.
+ * @param {?Node<vec3>} [uvNode=null] - The uv node.
+ * @param {?Node<int>} [levelNode=null] - The level node.
+ * @param {?Node<float>} [biasNode=null] - The bias node.
+ * @returns {TextureNode}
+ */
+export const texture3DLoad = ( ...params ) => texture3D( ...params ).setSampler( false );
+
+/**
+ * TSL function for creating a texture node that fetches/loads texels without interpolation.
+ *
+ * @tsl
+ * @function
+ * @param {?(Texture|TextureNode)} [value=EmptyTexture] - The texture.
+ * @param {?Node<vec3>} [uvNode=null] - The uv node.
+ * @param {?Node<int>} [levelNode=null] - The level node.
+ * @returns {TextureNode}
+ */
+export const texture3DLevel = ( value, uvNode, levelNode ) => texture3D( value, uvNode ).level( levelNode );