@thi.ng/shader-ast/ast/scope.js

DSL to define shader code in TypeScript and cross-compile to GLSL, JS and other targets

import { isArray } from "@thi.ng/checks/is-array";
import { DGraph } from "@thi.ng/dgraph";
import { isMat, isTerm, isVec } from "./checks.js";
const scopedChildren = (t) => {
  let children;
  switch (t.tag) {
    case "scope":
      return t.body;
    case "fn":
      return t.scope.body;
    case "for":
      children = [t.test, ...t.scope.body];
      if (t.init) children.push(t.init);
      if (t.iter) children.push(t.iter);
      return children;
    case "while":
      return [t.test, ...t.scope.body];
    case "if":
      children = [t.test, ...t.t.body];
      if (t.f) children.push(...t.f.body);
      return children;
  }
};
const allChildren = (t) => scopedChildren(t) || (t.tag === "scope" ? t.body : t.tag === "ternary" ? [t.test, t.t, t.f] : t.tag === "ret" ? t.val !== void 0 ? [t.val] : void 0 : t.tag === "call" || t.tag === "call_i" ? t.args : t.tag === "sym" && t.init ? [t.init] : t.tag === "decl" ? [t.id] : t.tag === "op1" || t.tag === "swizzle" ? [t.val] : t.tag === "op2" ? [t.l, t.r] : t.tag === "assign" ? [t.r] : isVec(t) || isMat(t) ? t.val : isTerm(t.val) ? t.val : void 0);
const walk = (visit, children, acc, tree, pre = true) => {
  if (isArray(tree)) {
    tree.forEach((x) => acc = walk(visit, children, acc, x, pre));
  } else {
    pre && (acc = visit(acc, tree));
    const c = children(tree);
    c && (acc = walk(visit, children, acc, c, pre));
    !pre && (acc = visit(acc, tree));
  }
  return acc;
};
const buildCallGraph = (fn, graph = new DGraph()) => fn.deps?.length ? fn.deps.reduce(
  (graph2, d) => buildCallGraph(d, graph2.addDependency(fn, d)),
  graph
) : graph.addNode(fn);
const decl = (id) => ({
  tag: "decl",
  type: id.type,
  id
});
const scope = (body, global = false) => ({
  tag: "scope",
  type: "void",
  body: body.filter((x) => x != null).map((x) => x.tag === "sym" ? decl(x) : x),
  global
});
const program = (body) => {
  const syms = body.filter((x) => x.tag !== "fn");
  const g = body.reduce(
    (acc, x) => x.tag === "fn" ? buildCallGraph(x, acc) : acc,
    new DGraph()
  );
  return scope(syms.concat(g.sort()), true);
};
export {
  allChildren,
  buildCallGraph,
  decl,
  program,
  scope,
  scopedChildren,
  walk
};