feat(shader-ast-stdlib): variadic sdf isec/sub/union

thi-ng · Aug 9, 2021 · fbff935 · fbff935
1 parent 9d52838
commit fbff935
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Showing 3 changed files with 18 additions and 12 deletions.
diff --git a/packages/shader-ast-stdlib/src/sdf/isec.ts b/packages/shader-ast-stdlib/src/sdf/isec.ts
@@ -1,9 +1,11 @@
 import { FloatTerm, max } from "@thi.ng/shader-ast";
 
 /**
- * Inline function. SDF shape intersection (a & b).
+ * Inline function. Variadic SDF shape intersection (a & b) for any number of
+ * terms (at least 1 required).
  *
- * @param a - float
- * @param b - float
+ * @param a -
+ * @param terms -
  */
-export const sdfIntersect = (a: FloatTerm, b: FloatTerm) => max(b, a);
+export const sdfIntersect = (a: FloatTerm, ...terms: FloatTerm[]) =>
+    terms.reduce((a, b) => max(a, b), a);
diff --git a/packages/shader-ast-stdlib/src/sdf/sub.ts b/packages/shader-ast-stdlib/src/sdf/sub.ts
@@ -1,9 +1,11 @@
 import { FloatTerm, max, neg } from "@thi.ng/shader-ast";
 
 /**
- * Inline function.  SDF shape subtraction (a - b).
+ * Inline function. Variadic SDF shape subtraction (a - b) for any number of
+ * terms (at least 1 required).
  *
- * @param a - float
- * @param b - float
+ * @param a -
+ * @param terms -
  */
-export const sdfSubtract = (a: FloatTerm, b: FloatTerm) => max(neg(b), a);
+export const sdfSubtract = (a: FloatTerm, ...terms: FloatTerm[]) =>
+    terms.reduce((a, b) => max(a, neg(b)), a);
diff --git a/packages/shader-ast-stdlib/src/sdf/union.ts b/packages/shader-ast-stdlib/src/sdf/union.ts
@@ -1,12 +1,14 @@
 import { $x, defn, FloatTerm, lt, min, ret, ternary } from "@thi.ng/shader-ast";
 
 /**
- * Inline function. SDF shape union (a || b).
+ * Inline function. Variadic SDF shape union (a || b) for any number of terms
+ * (at least 1 required).
  *
- * @param a - float
- * @param b - float
+ * @param a -
+ * @param terms -
  */
-export const sdfUnion = (a: FloatTerm, b: FloatTerm) => min(a, b);
+export const sdfUnion = (a: FloatTerm, ...terms: FloatTerm[]) =>
+    terms.reduce((a, b) => min(a, b), a);
 
 /**
  * SDF shape union for vec2 terms, i.e. the common form where the X coord