@thi.ng/shader-ast-stdlib/math/interval.js

Function collection for modular GPGPU / shader programming with @thi.ng/shader-ast

import { F } from "@thi.ng/shader-ast/api/types";
import { ternary } from "@thi.ng/shader-ast/ast/controlflow";
import { defn, ret } from "@thi.ng/shader-ast/ast/function";
import { FLOAT0, FLOAT1, FLOAT2 } from "@thi.ng/shader-ast/ast/lit";
import { div, lt, mul, sub } from "@thi.ng/shader-ast/ast/ops";
import { sym } from "@thi.ng/shader-ast/ast/sym";
import {
  abs,
  ceil,
  floor,
  mix,
  mod,
  step
} from "@thi.ng/shader-ast/builtin/math";
const trunc = defn(F, null, [F], (x) => [
  ret(ternary(lt(x, FLOAT0), ceil(x), floor(x)))
]);
const modulo = defn(F, null, [F, F], (x, y) => [
  ret(sub(x, mul(y, trunc(div(x, y)))))
]);
const foldback01 = defn(F, null, [F], (x) => {
  let y;
  return [
    y = sym(mod(abs(x), FLOAT2)),
    ret(mix(y, sub(FLOAT2, y), step(FLOAT1, y)))
  ];
});
export {
  foldback01,
  modulo,
  trunc
};