Fixing Glow Effect Issues with Transparent Spheres in Three.js

Based on your description of the issues with the glowing spheres in your Three.js project, I can offer some suggestions to help make the glow effect consistent from all viewing angles.

Issue Analysis

The problems you're experiencing are common when working with transparent materials and post-processing effects like bloom:

1. The sphere appearing white from behind suggests material rendering issues
2. The glow effect only showing on the front surface indicates the bloom effect isn't properly processing the back faces

Potential Solutions

1. Material Configuration

Make sure your transparent material is properly configured:

JAVASCRIPTCopied
const material = new THREE.MeshBasicMaterial({
  color: 0xff0000,  // Red color
  transparent: true,
  opacity: 0.5,
  side: THREE.DoubleSide  // This is crucial for transparent objects
});

The THREE.DoubleSide setting is essential as it ensures both front and back faces of the geometry are rendered.

2. Bloom Effect Setup

For the selective bloom effect to work properly with transparent objects:

JAVASCRIPTCopied
// Make sure your bloom pass has appropriate settings
const bloomPass = new UnrealBloomPass(
  new THREE.Vector2(window.innerWidth, window.innerHeight),
  1.5,   // Strength
  0.4,   // Radius
  0.85   // Threshold
);

// Ensure your glowing objects are in the correct layer
glowingSphere.layers.enable(BLOOM_LAYER);

3. Rendering Order

Control the rendering order to ensure transparent objects are rendered correctly:

JAVASCRIPTCopied
// Set a higher renderOrder for transparent objects
glowingSphere.renderOrder = 1;

4. Alternative Approach

If the above solutions don't work, consider using an emissive material instead:

JAVASCRIPTCopied
const material = new THREE.MeshPhongMaterial({
  color: 0xff0000,
  transparent: true,
  opacity: 0.5,
  emissive: 0xff0000,
  emissiveIntensity: 1.0,
  side: THREE.DoubleSide
});

This approach can sometimes provide more consistent glowing results with the bloom effect.

Additional Considerations

• Make sure your camera's near and far planes are set appropriately
• Check if any other post-processing effects might be interfering with the bloom
• Consider adjusting the bloom threshold, strength, and radius parameters

These adjustments should help ensure your glowing effect appears consistently from all viewing angles, including through the back of the transparent spheres.