metal:shared-buffer

(metal:shared-buffer ctx bytes)

An MTLBuffer of bytes bytes in shared storage, whose contents the CPU rewrites -- what metal:buffer is not. A program that re-tessellates its geometry every frame allocates once here and metal:uploads per frame; how many it keeps in flight is its own business. Part of the metal package, a Metal drawing surface written in rontolisp over objc and loaded on first use: macOS (java -jar, the rontolisp binary, or a compiled .class / .jar; never a .wasm), with a display. See the macOS GUI guide.

CL-USER> (defvar *scratch* (metal:shared-buffer *ctx* (* 4 36 1024)))