From edddfd5879952ef8c06f51c82917fa0c5b7a1c00 Mon Sep 17 00:00:00 2001
From: Adam Wonak <adam.wonak@gmail.com>
Date: Tue, 1 Jul 2025 12:23:50 -0700
Subject: [PATCH] Optimize euclidean pattern by changing from an array of ints
 to a bitmask.

---
 examples/Gravity/euclidean.h | 27 ++++++++++++++++-----------
 1 file changed, 16 insertions(+), 11 deletions(-)

diff --git a/examples/Gravity/euclidean.h b/examples/Gravity/euclidean.h
index 57e5cb6..f18e0ac 100644
--- a/examples/Gravity/euclidean.h
+++ b/examples/Gravity/euclidean.h
@@ -1,7 +1,7 @@
 #ifndef EUCLIDEAN_H
 #define EUCLIDEAN_H
 
-#define MAX_PATTERN_LEN 16
+#define MAX_PATTERN_LEN 32
 
 struct PatternState {
     uint8_t steps;
@@ -26,9 +26,12 @@ class Pattern {
         updatePattern();
     }
 
-    PatternState GetState() { return {steps_, hits_}; }
+    PatternState GetState() const { return {steps_, hits_}; }
 
-    Step GetCurrentStep(byte i) { return pattern_[i]; }
+    Step GetCurrentStep(byte i) {
+        if (i >= MAX_PATTERN_LEN) return REST;
+        return (pattern_bitmap_ & (1UL << i)) ? HIT : REST;
+    }
 
     void SetSteps(int steps) {
         steps_ = constrain(steps, 1, MAX_PATTERN_LEN);
@@ -47,8 +50,6 @@ class Pattern {
     uint8_t GetHits() { return hits_; }
     uint8_t GetStepIndex() { return step_index_; }
 
-    // Get the current step value and advance the euclidean rhythm step index
-    // to the next step in the pattern.
     Step NextStep() {
         if (steps_ == 0) return REST;
 
@@ -61,19 +62,23 @@ class Pattern {
     uint8_t steps_ = 0;
     uint8_t hits_ = 0;
     volatile uint8_t step_index_ = 0;
-    Step pattern_[MAX_PATTERN_LEN];
+    uint32_t pattern_bitmap_ = 0;
 
-    // Update the euclidean rhythm pattern when attributes change.
+    // Update the euclidean rhythm pattern using bitmap
     void updatePattern() {
+        pattern_bitmap_ = 0; // Clear the bitmap
+
+        if (steps_ == 0) return;
+
         byte bucket = 0;
-        pattern_[0] = HIT;
+        // Set the first bit (index 0) if it's a HIT
+        pattern_bitmap_ |= (1UL << 0);
+
         for (int i = 1; i < steps_; i++) {
             bucket += hits_;
             if (bucket >= steps_) {
                 bucket -= steps_;
-                pattern_[i] = HIT;
-            } else {
-                pattern_[i] = REST;
+                pattern_bitmap_ |= (1UL << i);
             }
         }
     }