Light Beam Effect in Three.js

Based on the image and link you've shared, I can provide some insights about how this light beam effect might be implemented in Three.js, though I should note that I don't have direct access to the specific code used in that example.

Likely Implementation Techniques

This animated light beam effect is likely created using a combination of:

1. Volumetric Light Rays: These are typically implemented using either:

   • Shader-based solutions with custom materials
   • Multiple semi-transparent planes with gradient textures

2. Light Probe Techniques: The LightProbeGenerator utility in Three.js could be used to enhance the lighting effects and create realistic light interactions with the environment.

3. Particle Systems: The sparkle/dust effects within the beams might be implemented using particle systems.

Possible Implementation Approach

Here's a simplified approach to create a similar effect:

JAVASCRIPTCopied
// Create a light beam using a custom shader material
const lightBeamGeometry = new THREE.CylinderGeometry(0.1, 0.5, 10, 32, 1, true);
const lightBeamMaterial = new THREE.ShaderMaterial({
  uniforms: {
    time: { value: 0 },
    color: { value: new THREE.Color(0x00ffff) },
    intensity: { value: 1.5 }
  },
  vertexShader: `
    varying vec2 vUv;
    void main() {
      vUv = uv;
      gl_Position = projectionMatrix * modelViewMatrix * vec4(position, 1.0);
    }
  `,
  fragmentShader: `
    uniform float time;
    uniform vec3 color;
    uniform float intensity;
    varying vec2 vUv;
    
    void main() {
      // Create animated gradient effect
      float alpha = (1.0 - vUv.y) * 0.5 * (0.8 + 0.2 * sin(time * 2.0 + vUv.y * 10.0));
      
      // Add noise for volumetric effect
      float noise = fract(sin(vUv.y * 100.0 + time) * 1000.0);
      alpha *= (0.9 + 0.1 * noise);
      
      gl_FragColor = vec4(color * intensity, alpha);
    }
  `,
  transparent: true,
  side: THREE.DoubleSide,
  blending: THREE.AdditiveBlending
});

const lightBeam = new THREE.Mesh(lightBeamGeometry, lightBeamMaterial);
lightBeam.rotation.x = Math.PI / 2; // Orient the beam
scene.add(lightBeam);

// Animation loop
function animate() {
  requestAnimationFrame(animate);
  
  // Update time uniform for animation
  lightBeamMaterial.uniforms.time.value += 0.01;
  
  renderer.render(scene, camera);
}

Advanced Enhancements

For a more realistic effect like the one in your example:

1. Multiple Beams: Create several beams with different parameters and positions
2. Dust Particles: Add a particle system within the beams
3. Light Probes: Use the LightProbeGenerator to create realistic light interactions
4. Post-Processing: Add bloom and glow effects using Three.js post-processing

The LightProbeGenerator mentioned in the documentation could be particularly useful for creating realistic lighting interactions between the beams and surrounding objects in your scene.

To implement a more complete solution, you would need to combine these techniques and fine-tune the parameters to achieve the desired visual effect.