Feat: adding LPG

crates/forth/src/words/compile.rs

@@ -145,6 +145,7 @@ pub(super) fn simple_op(name: &str) -> Option<Op> {
         "ead" => Op::ModEnvAd,
         "eadr" => Op::ModEnvAdr,
         "eadsr" | "env" => Op::ModEnv,
+        "lpg" => Op::Lpg,
         _ => return None,
     })
 }

crates/forth/src/words/sound.rs

@@ -862,4 +862,14 @@ pub(super) const WORDS: &[Word] = &[
         compile: Simple,
         varargs: false,
     },
+    Word {
+        name: "lpg",
+        aliases: &[],
+        category: "Audio Modulation",
+        stack: "(min max depth --)",
+        desc: "Low pass gate: pairs amp envelope with lpf modulation",
+        example: "0.01 0.1 ad 200 8000 1 lpg .",
+        compile: Simple,
+        varargs: false,
+    },
 ];