pedalgen.ngjs

#!/usr/bin/env ngspicejs
// Pedalgen v0.1 - generate random guitar pedals
// linter: ngspicejs-lint
"use strict";

// include sources
var tune_gain = include('src/tune_gain.js');
var valid_current = include('src/valid_current.js');
var valid_thd = include('src/valid_thd.js');
var tran_check = include('src/tran_check.js');
var randomize_values = include('src/randomize_values.js');
var cache_element_by_name = include('src/cache_element_by_name.js');
var cache_net_element_pin = include('src/cache_net_element_pin.js');
var cache_edges = include('src/cache_edges.js');
var edge_exists = include('src/edge_exists.js');
var remove_parallel_capacitors = include('src/remove_parallel_capacitors.js');
var cache_net_element_type = include('src/cache_net_element_type.js');
var remove_series = include('src/remove_series.js');
var generate_pedal = include('src/generate_pedal.js');
var build_circuit = include('src/build_circuit.js');
var elements_to_short_bom = include('src/elements_to_short_bom.js');
var optimize_one = include('src/optimize_one.js');

ignore(cache_element_by_name, cache_net_element_pin, cache_net_element_type,
    cache_edges, edge_exists, remove_parallel_capacitors, remove_series);

// variables
var config = file_read_json('pedalgen.json'); // config file from current directory
var reason = tally('Reason');   // Why was generated pedal wrong
var batch = 'batch/' + (new Date()).toISOString().substr(0, 19).replace('T', '--').replace(/[\:]+/g, '-') + '/'; // batch/2023-12-21--08-30-57/
dir_create(batch);

// save copy of config file
file_write_json(batch + 'pedalgen.json', config, 4);

// validate config
if (Object.values(config.optimize).filter((a) => a).length > 1) {
    error('You can only optimize one value, make sure in config.optimize only 1 property is true!');
    exit(1);
}

// replace Math.random with seeded Mersenne twister
if (config.seed > 0) {
    warn('Using random seed ' + config.seed + ' (and same config) will always generate the same pedals, use it only for debugging!');
    mersenne_twister(config.seed).replace_math_random();
}

// header of index.html
var html = [];
html.push('<style>');
html.push('img.chart {width: 360px; height: 150px;}');
html.push('</style>');
html.push('');
html.push('<script>');
html.push('function audioOnPause(event) {');
html.push('  event.target.currentTime = 0;');
html.push('}');
html.push('var au = document.createElement("audio");');
html.push('function audio_play(src) {');
html.push('  au.src = src;');
html.push('  au.play();');
html.push('}');
html.push('window.addEventListener("DOMContentLoaded", function () {');
html.push('    var id = parseInt(document.location.hash.substr(1), 10);');
html.push('    var e = document.getElementById(id);');
html.push('    if (!e) { return; };');
html.push('    e.scrollIntoView();');
html.push('    e.style.backgroundColor = "skyblue";');
html.push('});');
html.push('</script>');
html.push('');
html.push('<h1>pedalgen v0.1 - ' + batch + '</h1>');

// main loop
var pedals_found = 0;
var topo_counter = 0;
while (true) {
    echo_progress();
    // generate pedal
    topo_counter++;
    echo('Generating new topology #' + topo_counter);
    var pedal = generate_pedal(config.complexity);
    // build ngspicejs circuit
    var cir = build_circuit(pedal.elements);
    // check for singular matrix
    if (singular_matrix()) {
        reason.inc('Simulation: Singular matrix');
        continue;
    }
    // check for timestep too small
    if (tran_check()) {
        reason.inc('Simulation: Timestep too small');
        continue;
    }
    // first do the gain alone to skip really poor topologies
    if (!tune_gain(config, randomize_values)) {
        reason.inc('Tune: First gain failed');
        continue;
    }

    // tune gain, check current and thd
    var passed = false;
    var score = 0;
    for (var i = 0; i < 100; i++) {
        echo_progress();

        if (i > 0 && !tune_gain(config, randomize_values)) {
            reason.inc('Tune: Second gain failed');
            continue;
        }
        score++;

        if (!valid_current(config)) {
            reason.inc('Tune: Current failed');
            randomize_values();
            continue;
        }
        score++;

        if (!valid_thd(config)) {
            reason.inc('Tune: THD failed');
            randomize_values();
            continue;
        }
        score++;
        passed = true;
        break;
    }
    echo('  Score', score, i);
    if (!passed) {
        continue;
    }

    // redo all analyses for passing pedal
    echo('  Pedal found!');
    var t = tran().start(config.tran.start).step(config.tran.step).interval(config.tran.interval).run();
    var current = t.rms('I(V2)');
    var a = ac().fstart(config.ac.fstart).fstop(config.ac.fstop).run();
    var gain = a.value_at('V(load)', config.input.frequency);
    var gain_tran = t.data['V(load)'].slice(100).amplitude() / config.input.amplitude;
    var f = fft().interval(config.fft.interval).fstop(config.fft.fstop).run('V(load)');
    var thd = f.thd(config.input.frequency, config.fft.harmonics);
    var even = f.even(config.input.frequency, config.fft.harmonics);
    var odd = f.odd(config.input.frequency, config.fft.harmonics);
    echo('  Current', current.toEng(), 'gain', gain, 'gain_tran', gain_tran, 'thd', thd, 'even', even, 'odd', odd);

    // optimize
    if (!optimize_one('max gain', gain)) {
        continue;
    }
    if (!optimize_one('min current', current)) {
        continue;
    }
    if (!optimize_one('min thd', thd)) {
        continue;
    }
    if (!optimize_one('max thd', thd)) {
        continue;
    }
    if (!optimize_one('max even', even)) {
        continue;
    }
    if (!optimize_one('max odd', odd)) {
        continue;
    }
    if (!optimize_one('max thd*even', thd * even)) {
        continue;
    }
    if (!optimize_one('max thd*odd', thd * odd)) {
        continue;
    }

    // show charts
    t.chart('V(load)', {width: 360, height: 150});
    f.chart_db('V(load)', {width: 360, height: 150});
    a.chart('V(load)', {width: 360, height: 150});

    // create pedal folder
    var timestamp = Date.now();
    var folder = timestamp.toString() + '/';
    var path = batch + folder;
    dir_create(path);

    // save charts as gifs
    t.last_chart.gif(path + 'tran.gif');
    f.last_chart.gif(path + 'fft.gif');
    a.last_chart.gif(path + 'ac.gif');

    // write other files
    file_write_json(path + 'netlist.json', netlist_export(), 4);
    file_write_json(path + 'schematic.netlist', netlist_export_schematic(['RS','LS','V1','CP','RP','RLOAD']), 4);
    file_write_ngspicejs(path + 'netlist.ngjs');
    file_mode(path + 'netlist.ngjs', parseInt('755', 8));

    // create sharable url
    var schematic = netlist_export_schematic_url(['RS','LS','V1', 'CP','RP','RLOAD']);
    // add ground symbol
    schematic += '|ground,Ground,,0';
    // add in and out connectors
    schematic += '|connector,IN,,sig|connector,OUT,,load';
    file_write(path + 'schematic.url', schematic);

    // write summary.json
    var summary = {
        timestamp,
        path,
        folder,
        current,
        gain: gain,
        thd,
        even,
        odd,
        schematic
    };
    file_write_json(path + 'summary.json', summary, 4);

    // replace pickup sinewave with audio source and save the output
    if (config.input.wav) {
        cir.v1.remove();
        cir.v1 = audio('V1', 'sig2', 0).filename(config.input.wav || 'wav/chord.wav').v(config.input.amplitude);
        // add tran and wav saving command to saved script (if user wants to re-run it later)
        file_write_ngspicejs(path + 'netlist_wav.ngjs');
        var src = file_read(path + 'netlist_wav.ngjs').split('\n');
        src.push('echo("running tran");');
        src.push('var t = tran().interval(3.5).step("20.833u").run();');
        src.push('echo("saving wav");');
        src.push('file_write_wav("output.wav", t.data.time, t.data["V(load)"], undefined);');
        src.push('echo("done");');
        src = src.join('\n').replace('wav/chord.m', '../../../wav/chord.wav');
        file_write(path + 'netlist_wav.ngjs', src);
        file_mode(path + 'netlist_wav.ngjs', parseInt('755', 8));
        // run tran and save wav
        echo('Saving audio...');
        t = tran().interval(cir.v1.get_duration() - 0.001).step('20.833u').run();
        file_write_wav(path + 'output.wav', t.data.time, t.data['V(load)'], undefined);
    }

    // add pedal to index.html
    html.push('<div id="' + summary.timestamp + '">');
    html.push('  <button class="play" onclick="audio_play(\'../../' + config.input.wav + '\')">input</button>');
    html.push('  <button class="play" onclick="audio_play(\'' + summary.timestamp + '/output.wav\')">play</button>');
    html.push('  <b>pedalgen.' + summary.timestamp + '</b> - ');
    html.push('  Current ' + summary.current.toEng() + 'A, ');
    html.push('  Gain ' + summary.gain.toFixed(3) + 'x, ');
    html.push('  THD ' + (100 * summary.thd).toFixed(1) + '%, ');
    html.push('  Even ' + (100 * summary.even).toFixed(1) + '%, ');
    html.push('  Odd ' + (100 * summary.odd).toFixed(1) + '%, ');
    html.push('  <a href="' + summary.schematic + '">Schematic</a>, ');
    html.push('  ' + elements_to_short_bom(pedal.elements));
    html.push('</div>');
    html.push('<div>');
    var ac_title = '???'; //p.ac_points.map(a => a.value.toFixed(3) + 'V @' + a.frequency.toEng() + 'Hz').join(', ');
    html.push('  <img class="chart" src="' + summary.folder + 'tran.gif">');
    html.push('  <img class="chart" src="' + summary.folder + 'fft.gif">');
    html.push('  <img class="chart" src="' + summary.folder + 'ac.gif" title="' + ac_title + '">');
    html.push('</div>');
    html.push('<hr>');
    file_write(batch + 'index.html', html.join('\n'));

    // beep
    echo('pedal ' + (pedals_found + 1) + '/' + config.generate_how_many_pedals + ' found');
    beep();

    // stop after enough pedals are found
    pedals_found++;
    if (pedals_found >= config.generate_how_many_pedals) {
        reason.echo();
        file_write_json(batch + 'reason.json', reason.counts, 4);
        echo('Generated ' + pedals_found + ' pedals in ' + (script_ms() / 1000 / 60).toFixed(0) + ' minutes');
        break;
    }
}