feat(shader-ast-stdlib): add snoise2, distance fns

packages/shader-ast-stdlib/src/index.ts

@@ -9,7 +9,10 @@ export * from "./lighting/trilight";
 
 export * from "./math/clamp";
 export * from "./math/cross2";
+export * from "./math/dist-chebyshev";
+export * from "./math/dist-manhattan";
 export * from "./math/fit";
+export * from "./math/magsq";
 export * from "./math/maxcomp";
 export * from "./math/mincomp";
 export * from "./math/orthogonal";
@@ -18,8 +21,10 @@ export * from "./matrix/lookat";
 export * from "./matrix/mvp";
 export * from "./matrix/normal";
 
+export * from "./noise/hash3";
 export * from "./noise/permute";
-export * from "./noise/voronoise";
+export * from "./noise/simplex2";
+export * from "./noise/voronoi2";
 export * from "./noise/worley2";
 
 export * from "./raymarch/ao";

packages/shader-ast-stdlib/src/math/dist-chebyshev.ts

@@ -0,0 +1,25 @@
+import {
+    $w,
+    $x,
+    $y,
+    $z,
+    abs,
+    max,
+    sub,
+    Vec2Term,
+    Vec3Term,
+    Vec4Term
+} from "@thi.ng/shader-ast";
+
+export const distChebyshev2 = (
+    a: Vec2Term | Vec3Term | Vec4Term,
+    b: Vec2Term | Vec3Term | Vec4Term
+) => max(abs(sub($x(a), $x(b))), abs(sub($y(a), $y(b))));
+
+export const distChebyshev3 = (
+    a: Vec3Term | Vec4Term,
+    b: Vec3Term | Vec4Term
+) => max(distChebyshev2(a, b), abs(sub($z(a), $z(b))));
+
+export const distChebyshev4 = (a: Vec4Term, b: Vec4Term) =>
+    max(distChebyshev3(a, b), abs(sub($w(a), $w(b))));

packages/shader-ast-stdlib/src/math/dist-manhattan.ts

@@ -0,0 +1,25 @@
+import {
+    $w,
+    $x,
+    $y,
+    $z,
+    abs,
+    add,
+    sub,
+    Vec2Term,
+    Vec3Term,
+    Vec4Term
+} from "@thi.ng/shader-ast";
+
+export const distManhattan2 = (
+    a: Vec2Term | Vec3Term | Vec4Term,
+    b: Vec2Term | Vec3Term | Vec4Term
+) => add(abs(sub($x(a), $x(b))), abs(sub($y(a), $y(b))));
+
+export const distManhattan3 = (
+    a: Vec3Term | Vec4Term,
+    b: Vec3Term | Vec4Term
+) => add(distManhattan2(a, b), abs(sub($z(a), $z(b))));
+
+export const distManhattan4 = (a: Vec4Term, b: Vec4Term) =>
+    add(distManhattan3(a, b), abs(sub($w(a), $w(b))));

packages/shader-ast-stdlib/src/math/magsq.ts

@@ -0,0 +1,13 @@
+import { defn, dot, ret } from "@thi.ng/shader-ast";
+
+export const magSq2 = defn("float", "magSq2", [["vec2"]], (v) => [
+    ret(dot(v, v))
+]);
+
+export const magSq3 = defn("float", "magSq3", [["vec3"]], (v) => [
+    ret(dot(v, v))
+]);
+
+export const magSq4 = defn("float", "magSq4", [["vec4"]], (v) => [
+    ret(dot(v, v))
+]);

packages/shader-ast-stdlib/src/noise/simplex2.ts

@@ -0,0 +1,106 @@
+import {
+    $,
+    $x,
+    $y,
+    abs,
+    add,
+    assign,
+    defn,
+    dot,
+    float,
+    FLOAT05,
+    FLOAT1,
+    floor,
+    fract,
+    gt,
+    max,
+    mod,
+    mul,
+    ret,
+    sub,
+    sym,
+    ternary,
+    vec2,
+    Vec2Sym,
+    vec3,
+    Vec3Sym,
+    vec4,
+    Vec4Sym
+} from "@thi.ng/shader-ast";
+import { magSq2 } from "../math/magsq";
+import { permute3 } from "./permute";
+
+/**
+ * Array and textureless GLSL 2D simplex noise function. Ported from
+ * original GLSL implementation by Ian McEwan & Ashima Arts.
+ *
+ * https://github.com/ashima/webgl-noise
+ */
+export const snoise2 = defn("float", "snoise2", [["vec2"]], (v) => {
+    let C: Vec4Sym;
+    let i: Vec2Sym;
+    let i1: Vec2Sym;
+    let x0: Vec2Sym;
+    let x12: Vec4Sym;
+    let p: Vec3Sym;
+    let m: Vec3Sym;
+    let x: Vec3Sym;
+    let h: Vec3Sym;
+    let ox: Vec3Sym;
+    let a0: Vec3Sym;
+    let g: Vec3Sym;
+    return [
+        (C = sym(
+            vec4(
+                0.211324865405187,
+                0.366025403784439,
+                -0.577350269189626,
+                0.024390243902439
+            )
+        )),
+        (i = sym(floor(add(v, dot(v, $(C, "yy")))))),
+        (x0 = sym(add(sub(v, i), dot(i, $(C, "xx"))))),
+        (i1 = sym(ternary(gt($x(x0), $y(x0)), vec2(1, 0), vec2(0, 1)))),
+        (x12 = sym(sub(add($(x0, "xyxy"), $(C, "xxzz")), vec4(i1, 0, 0)))),
+        assign(i, mod(i, float(289))),
+        (p = sym(
+            permute3(
+                add(
+                    permute3(add(vec3(0, $y(i1), 1), $y(i))),
+                    add(vec3(0, $x(i1), 1), $x(i))
+                )
+            )
+        )),
+        (m = sym(
+            max(
+                sub(
+                    FLOAT05,
+                    vec3(magSq2(x0), magSq2($(x12, "xy")), magSq2($(x12, "zw")))
+                ),
+                vec3()
+            )
+        )),
+        assign(m, mul(m, m)),
+        assign(m, mul(m, m)),
+        (x = sym(sub(mul(2, fract(mul(p, $(C, "www")))), FLOAT1))),
+        (h = sym(sub(abs(x), FLOAT05))),
+        (ox = sym(floor(add(x, FLOAT05)))),
+        (a0 = sym(sub(x, ox))),
+        assign(
+            m,
+            mul(
+                m,
+                sub(
+                    1.79284291400159,
+                    mul(0.85373472095314, add(mul(a0, a0), mul(h, h)))
+                )
+            )
+        ),
+        (g = sym(vec3(add(mul($x(a0), $x(x0)), mul($x(h), $y(x0)))))),
+        assign(
+            $(g, "yz"),
+            add(mul($(a0, "yz"), $(x12, "xz")), mul($(h, "yz"), $(x12, "yw")))
+        ),
+        ret(mul(130, dot(m, g)))
+    ];
+});