luma.gl/docs/api-guide/buffers.md

Using GPU Buffers

Buffer Operations

The ability to copy memory between CPU, buffers and textures

Dimension	WebGPU	WebGL2	WebGL1	Description
writeBuffe	✅	✅	✅	Read a buffer synchronously
readBuffer (sync)	❌	✅	✅	Read a buffer synchronously
readBuffer (async)	✅	❌ *	❌ *	Read a buffer asynchronously
copyBufferToBuffer	✅	✅	❌	Copy a buffer to another buffer without CPU roundtrip
copyBufferToTexture	✅	✅	❌	Copy a buffer to a texture without CPU roundtrip
copyTextureToBuffer	✅	✅	❌	Copy a buffer to a texture without CPU roundtrip

Remarks:

• A WebGL extension does exist that enables asynchronous buffer reads, but it is not implemented on MacOS which is the primary development environment for luma.gl.
• Asynchronous reads are emulated by luma.gl by providing a Promise style API. The actual reads are still asynchronous though.