More strategies

2026-02-18 19:31:38 +01:00
parent da30471f31
commit 07c30d20ef
4 changed files with 412 additions and 2 deletions
@@ -0,0 +1,163 @@
+#ifndef LSYSTEM_STRATEGY_H
+#define LSYSTEM_STRATEGY_H
+
+#include "MelodyStrategy.h"
+#include <Arduino.h>
+
+struct Rule {
+    char from;
+    const char* to;
+};
+
+struct RuleSet {
+    const char* axiom;
+    const Rule* rules;
+    uint8_t numRules;
+};
+
+// --- L-System Rule Definitions ---
+const Rule rules1[] = { {'A', "B-A-B"}, {'B', "A+B+A"} };
+const Rule rules2[] = { {'F', "F+F-F-F+F"} };
+const Rule rules3[] = { {'X', "F+[[X]-X]-F[-FX]+X"}, {'F', "FF"} };
+
+const RuleSet ruleSets[] = {
+    {"A", rules1, 2},      // Sierpinski triangle
+    {"F", rules2, 1},      // Koch curve
+    {"X", rules3, 2}       // Fractal plant
+};
+const uint8_t numRuleSets = sizeof(ruleSets) / sizeof(RuleSet);
+
+class LSystemStrategy : public MelodyStrategy {
+public:
+    void generate(Step (*sequence)[NUM_STEPS], int track, int numSteps, int* scaleNotes, int numScaleNotes, int seed) override {
+        randomSeed(seed);
+        if (numScaleNotes == 0) {
+            // Fill with silence if no scale
+            for (int i = 0; i < numSteps; i++) {
+                sequence[track][i].note = -1;
+                sequence[track][i].accent = false;
+                sequence[track][i].tie = false;
+            }
+            return;
+        }
+
+        // 1. Select a rule set and expand the axiom
+        const RuleSet& selectedRuleSet = ruleSets[random(numRuleSets)];
+        String currentString = selectedRuleSet.axiom;
+        int iterations = random(2, 5); // 2-4 iterations
+
+        for (int i = 0; i < iterations; i++) {
+            String nextString = "";
+            for (char c : currentString) {
+                bool replaced = false;
+                for (int j = 0; j < selectedRuleSet.numRules; j++) {
+                    if (c == selectedRuleSet.rules[j].from) {
+                        nextString += selectedRuleSet.rules[j].to;
+                        replaced = true;
+                        break;
+                    }
+                }
+                if (!replaced) {
+                    nextString += c;
+                }
+                if (nextString.length() > 256) break; // Memory safety
+            }
+            currentString = nextString;
+            if (currentString.length() > 256) break;
+        }
+
+        // 2. Interpret the string to create the sequence
+        int stepIndex = 0;
+        int noteIndex = random(numScaleNotes);
+        int octave = 4;
+
+        // Stack for branching rules
+        int note_stack[8];
+        int octave_stack[8];
+        int stack_ptr = 0;
+
+        for (char c : currentString) {
+            if (stepIndex >= numSteps) break;
+
+            switch(c) {
+                case 'F': case 'G': case 'A': case 'B': // Characters that draw notes
+                    sequence[track][stepIndex].note = 12 * octave + scaleNotes[noteIndex];
+                    sequence[track][stepIndex].accent = (random(100) < 25);
+                    sequence[track][stepIndex].tie = (random(100) < 10);
+                    stepIndex++;
+                    break;
+                case '+': // Go up in scale
+                    noteIndex = (noteIndex + 1) % numScaleNotes;
+                    break;
+                case '-': // Go down in scale
+                    noteIndex = (noteIndex - 1 + numScaleNotes) % numScaleNotes;
+                    break;
+                case '[': // Push current state
+                    if(stack_ptr < 8) {
+                        note_stack[stack_ptr] = noteIndex;
+                        octave_stack[stack_ptr] = octave;
+                        stack_ptr++;
+                    }
+                    break;
+                case ']': // Pop state
+                    if(stack_ptr > 0) {
+                        stack_ptr--;
+                        noteIndex = note_stack[stack_ptr];
+                        octave = octave_stack[stack_ptr];
+                    }
+                    break;
+                // Any other characters (like 'X' in rule 3) are ignored for drawing
+            }
+        }
+
+        // 3. Fill any remaining steps with rests
+        for (int i = 0; i < numSteps; i++) {
+            if (i >= stepIndex) {
+                sequence[track][i].note = -1;
+                sequence[track][i].accent = false;
+                sequence[track][i].tie = false;
+            }
+        }
+        randomSeed(micros());
+    }
+
+    void generateScale(int* scaleNotes, int& numScaleNotes) override {
+        numScaleNotes = random(5, 8);
+        for (int i = 0; i < 12; i++) {
+            scaleNotes[i] = i;
+        }
+        for (int i = 0; i < 12; i++) {
+            int j = random(12);
+            int temp = scaleNotes[i];
+            scaleNotes[i] = scaleNotes[j];
+            scaleNotes[j] = temp;
+        }
+        sortArray(scaleNotes, numScaleNotes);
+    }
+
+    void mutate(Step (*sequence)[NUM_STEPS], int track, int numSteps, int* scaleNotes, int numScaleNotes) override {
+        // Swap two non-rest steps to create a variation
+        int s1 = random(numSteps);
+        int s2 = random(numSteps);
+        int attempts = 0;
+
+        // Try to find two different, non-rest steps
+        while((sequence[track][s1].note == -1 || sequence[track][s2].note == -1 || s1 == s2) && attempts < 20) {
+            s1 = random(numSteps);
+            s2 = random(numSteps);
+            attempts++;
+        }
+
+        if (sequence[track][s1].note != -1 && sequence[track][s2].note != -1) {
+            Step temp = sequence[track][s1];
+            sequence[track][s1] = sequence[track][s2];
+            sequence[track][s2] = temp;
+        }
+    }
+
+    const char* getName() override {
+        return "L-System";
+    }
+};
+
+#endif