# Water2: Getting Error While Trying to add custom Shader to Water2.js, R3F

**URL:** <https://discourse.threejs.org/t/water2-getting-error-while-trying-to-add-custom-shader-to-water2-js-r3f/76640>\
**Category:** Questions\
**Tags:** materials, shaders, react-three-fiber\
**Created:** [January 17, 2025, 3:42pm UTC](https://discourse.threejs.org/t/water2-getting-error-while-trying-to-add-custom-shader-to-water2-js-r3f/76640 "2025-01-17T15:42:54Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![srinivas\_work](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.threejs.org/srinivas_work/32/55735_2.png) [@srinivas\_work](https://discourse.threejs.org/u/srinivas_work)\
**Post date:** [January 17, 2025, 3:42pm UTC](https://discourse.threejs.org/t/water2-getting-error-while-trying-to-add-custom-shader-to-water2-js-r3f/76640/1 "2025-01-17T15:42:54Z")

</div>

I’m new to three.js and trying to add custom shader to the Water2.js for more realistic feel but I’m getting error while adding the shader. _The current shader is a demo shader_

```javascript
import { useFrame, useLoader } from "@react-three/fiber";
import { useEffect, useRef } from "react";
import * as THREE from "three";
import { Water2 } from "three/examples/jsm/Addons.js";

const WaterEx = () => {
  const waterRef = useRef<THREE.Group>(null);
  const waterNormals = useLoader(
    THREE.TextureLoader,
    "https://raw.githubusercontent.com/mrdoob/three.js/master/examples/textures/waternormals.jpg"
  );

  const customShader = {
    uniforms: {
      time: { value: 0.0 },
      customColor: { value: new THREE.Color(0x001e0f) },
    },
    vertexShader: `
      uniform float time;
      varying vec3 vWorldPosition;
      void main() {
        vWorldPosition = position + normal * sin(time + position.x * 0.1) * 0.5;
        gl_Position = projectionMatrix * modelViewMatrix * vec4(vWorldPosition, 1.0);
      }
    `,
    fragmentShader: `
      uniform vec3 customColor;
      varying vec3 vWorldPosition;
      void main() {
        gl_FragColor = vec4(customColor * abs(vWorldPosition.y), 1.0);
      }
    `,
  };

  useEffect(() => {
    if (waterRef.current) {
      waterNormals.wrapS = waterNormals.wrapT = THREE.RepeatWrapping;

      const waterGeometry = new THREE.PlaneGeometry(100, 100);
      const water = new Water2(waterGeometry, {
        color: 0xffffff,
        scale: 4,
        flowDirection: new THREE.Vector2(1, 1),
        textureWidth: 1024,
        textureHeight: 1024,
        normalMap0: waterNormals,
        normalMap1: waterNormals,
        shader: customShader,
      });

      water.rotation.x = -Math.PI / 2; // Rotate to lay flat
      waterRef.current.add(water);

      return () => {
        waterGeometry.dispose();
      };
    }
  }, []);

  useFrame(() => {
    if (waterRef.current) {
      const water = waterRef.current.children[0] as Water2;
      water.material.uniforms["time"].value -= 0.4 / 60.0;
    }
  });

  return <group ref={waterRef} />;
};

export default WaterEx;

```

Error:

```javascript
Uncaught TypeError: Cannot set properties of undefined (setting 'value')
    at WaterEx.tsx:40:21
chunk-NG4E3QU3.js?v=3e5ebd4f:18163 The above error occurred in the <WaterEx> component:

    at WaterEx (http://localhost:5174/src/components/WaterEx.tsx?t=1737093630107:24:20)
    at Suspense
    at Suspense
    at ErrorBoundary (http://localhost:5174/node_modules/.vite/deps/chunk-NG4E3QU3.js?v=3e5ebd4f:16546:5)
    at FiberProvider (http://localhost:5174/node_modules/.vite/deps/chunk-NG4E3QU3.js?v=3e5ebd4f:18166:21)
    at Provider (http://localhost:5174/node_modules/.vite/deps/chunk-NG4E3QU3.js?v=3e5ebd4f:17833:3)

React will try to recreate this component tree from scratch using the error boundary you provided, ErrorBoundary.

2
chunk-NG4E3QU3.js?v=3e5ebd4f:18431 Uncaught TypeError: Cannot set properties of undefined (setting 'value')
    at WaterEx.tsx:40:21
chunk-NG4E3QU3.js?v=3e5ebd4f:18163 The above error occurred in the <ForwardRef(Canvas)> component:

    at Canvas (http://localhost:5174/node_modules/.vite/deps/chunk-NG4E3QU3.js?v=3e5ebd4f:18391:3)
    at FiberProvider (http://localhost:5174/node_modules/.vite/deps/chunk-NG4E3QU3.js?v=3e5ebd4f:18166:21)
    at CanvasWrapper
    at App (http://localhost:5174/src/App.tsx?t=1737093567626:31:20)

Consider adding an error boundary to your tree to customize error handling behavior.
Visit https://reactjs.org/link/error-boundaries to learn more about error boundaries.
chunk-PJEEZAML.js?v=3e5ebd4f:19413 Uncaught TypeError: Cannot set properties of undefined (setting 'value')
    at WaterEx.tsx:40:21

```