metal:pipeline

(metal:pipeline ctx lib vertex-name fragment-name &key blend)

An MTLRenderPipelineState over the two named functions of lib, drawing into the layer's pixel format. :blend makes it additive (one + one), which is what a glow pass wants. The depth attachment format follows the context rather than the caller, because a pipeline's attachments must match the pass it draws into. 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 *solid* (metal:pipeline *ctx* *lib* "solid_vertex" "solid_fragment"))
CL-USER> (defvar *glow* (metal:pipeline *ctx* *lib* "sprite_vertex" "sprite_fragment" :blend t))