WebGLProgram Accumulation Issue

Based on the information available, I can address your issue regarding the accumulation of WebGLProgram objects when updating material textures.

Understanding the Issue

When you set a material's map property and trigger material.needsUpdate = true, Three.js creates a new WebGLProgram to handle the updated material configuration. This is expected behavior, as Three.js needs to compile new shader programs when material properties change significantly.

JAVASCRIPTCopied
material.map = new THREE.Texture()
material.needsUpdate = true

Each time this sequence is executed, a new WebGLProgram is created, which explains the increasing count in renderer.info.programs.

Proper Resource Management

You don't need to dispose of the material before setting its map property. However, you should:

1. Dispose of old textures if you're replacing them to prevent memory leaks
2. Dispose of materials when they're no longer needed in your application

Recommended Approach

If you're frequently updating textures on the same material:

JAVASCRIPTCopied
// If there's an existing texture, dispose it first
if (material.map) {
    material.map.dispose();
}

// Set the new texture
material.map = new THREE.Texture();
material.needsUpdate = true;

When you're completely done with a material:

JAVASCRIPTCopied
// Dispose textures first
if (material.map) material.map.dispose();
// Dispose other texture maps if present (normalMap, aoMap, etc.)

// Then dispose the material
material.dispose();

Renderer Cleanup

When your application is shutting down or when you're done with a renderer instance, make sure to call:

JAVASCRIPTCopied
renderer.dispose();

This will free up GPU-related resources allocated by the renderer instance, which is crucial for preventing memory leaks in applications that create and destroy multiple renderers.

The accumulation of WebGLProgram objects is normal during material updates, but proper disposal of resources when they're no longer needed will help manage memory usage in your application.