ShaderMaterial

• uniforms entries must be objects like a value wrapper, not raw numbers.
• Built-ins such as modelViewMatrix, projectionMatrix, position, and uv are injected automatically.
• Set glslVersion to THREE.GLSL3 for GLSL ES 3.0 syntax.

const uniforms = {
  uTime: { value: 0 },
  uColor: { value: new THREE.Color('#4aa3df') },
  uAmplitude: { value: 1.4 }
};

const material = new THREE.ShaderMaterial({
  uniforms: uniforms,
  vertexShader: `
    uniform float uTime;
    uniform float uAmplitude;
    varying float vHeight;

    void main() {
      vec3 p = position;
      float h = sin(p.x * 0.8 + uTime) * cos(p.z * 0.8 + uTime) * uAmplitude;
      p.y += h;
      vHeight = h;
      gl_Position = projectionMatrix * modelViewMatrix * vec4(p, 1.0);
    }
  `,
  fragmentShader: `
    uniform vec3 uColor;
    varying float vHeight;

    void main() {
      vec3 c = mix(uColor, vec3(1.0), clamp(vHeight * 0.4 + 0.4, 0.0, 1.0));
      gl_FragColor = vec4(c, 1.0);
    }
  `,
  side: THREE.DoubleSide
});

function animate(t) {
  uniforms.uTime.value = t * 0.001;
  renderer.render(scene, camera);
}

• Shared uniforms objects affect every material referencing them; clone with UniformsUtils.clone().
• Changing defines requires recompilation, so plan macro combinations rather than toggling often.