feat: add microui-based GUI with transport controls and progress bar

Co-authored-by: aider (deepseek/deepseek-coder) <aider@aider.chat>
2026-05-01 13:02:39 +00:00
parent 3b95c22736
commit 05c6f34b8f
7 changed files with 473 additions and 3 deletions
--- a/docs/usage.md
+++ b/docs/usage.md
@@ -1741,3 +1741,26 @@ clicked increments that integer, could be implemented as such:</p>
  </body>
 </html>

+# Usage
+
+## Overview
+
+The Jack Looper application provides a simple audio loop player using JACK.
+
+## Getting Started
+
+1. Ensure JACK is running
+2. Run `./jack-looper`
+3. Use the TUI interface to control playback
+
+## Controls
+
+- Space: Play/Stop
+- Up/Down: Change BPM
+- Left/Right: Change loop length
+- R: Reset beat position
+- Q: Quit
+
+## Building
+
+Run `make` to build all targets.
--- a/engine.c
+++ b/engine.c
@@ -510,3 +510,114 @@ const char* quantize_mode_to_string(QuantizeMode mode) {
        default: return "Unknown";
    }
 }
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include <jack/jack.h>
+#include "engine.h"
+
+static float *audio_buffer = NULL;
+static int buffer_size = 0;
+static float bpm = 120.0f;
+static int loop_length = 8;
+static int current_beat = 0;
+static int active = 0;
+static jack_nframes_t sample_rate = 0;
+static jack_port_t *output_port = NULL;
+
+static int process_callback(jack_nframes_t nframes, void *arg)
+{
+    (void)arg;
+    jack_default_audio_sample_t *out = jack_port_get_buffer(output_port, nframes);
+    if (!out) return 0;
+
+    /* simple metronome: generate a click on each beat */
+    float samples_per_beat = sample_rate * 60.0f / bpm;
+    static float phase = 0.0f;
+
+    for (jack_nframes_t i = 0; i < nframes; i++) {
+        if (phase >= samples_per_beat) {
+            phase -= samples_per_beat;
+            current_beat = (current_beat + 1) % loop_length;
+        }
+
+        float sample = 0.0f;
+        if (active) {
+            /* short click at start of beat */
+            float click_duration = samples_per_beat * 0.05f;
+            if (phase < click_duration) {
+                float t = phase / click_duration;
+                sample = sinf(t * M_PI) * 0.3f;
+            }
+        }
+        out[i] = sample;
+        phase += 1.0f;
+    }
+
+    return 0;
+}
+
+int engine_init(jack_client_t *client, float *buffer, int buf_size)
+{
+    audio_buffer = buffer;
+    buffer_size = buf_size;
+
+    sample_rate = jack_get_sample_rate(client);
+
+    output_port = jack_port_register(client, "output",
+                                     JACK_DEFAULT_AUDIO_TYPE,
+                                     JackPortIsOutput, 0);
+    if (!output_port) {
+        fprintf(stderr, "no more JACK ports available\n");
+        return -1;
+    }
+
+    jack_set_process_callback(client, process_callback, NULL);
+
+    if (jack_activate(client)) {
+        fprintf(stderr, "cannot activate client\n");
+        return -1;
+    }
+
+    return 0;
+}
+
+void engine_cleanup(jack_client_t *client)
+{
+    jack_deactivate(client);
+    jack_port_unregister(client, output_port);
+}
+
+int engine_start(jack_client_t *client)
+{
+    (void)client;
+    active = 1;
+    return 0;
+}
+
+int engine_stop(jack_client_t *client)
+{
+    (void)client;
+    active = 0;
+    return 0;
+}
+
+void engine_set_bpm(jack_client_t *client, float new_bpm)
+{
+    (void)client;
+    bpm = new_bpm;
+}
+
+void engine_set_loop_length(jack_client_t *client, int beats)
+{
+    (void)client;
+    loop_length = beats;
+    if (current_beat >= loop_length) current_beat = 0;
+}
+
+int engine_get_current_beat(jack_client_t *client)
+{
+    (void)client;
+    return current_beat;
+}
--- a/gui.c
+++ b/gui.c
@@ -0,0 +1,221 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include <jack/jack.h>
+#include <ncurses.h>
+#include "engine.h"
+#include "gui.h"
+
+/* microui includes */
+#define MU_IMPLEMENTATION
+#include "microui.h"
+
+/* ---------------------------------------------------------------------------
+ *  microui callbacks
+ * ------------------------------------------------------------------------- */
+static int text_width(mu_Font font, const char *text, int len)
+{
+    (void)font;
+    if (len == -1) { len = strlen(text); }
+    return len * 8;
+}
+
+static int text_height(mu_Font font)
+{
+    (void)font;
+    return 18;
+}
+
+/* ---------------------------------------------------------------------------
+ *  global state
+ * ------------------------------------------------------------------------- */
+static mu_Context *ctx = NULL;
+
+static int running = 1;
+
+/* engine state */
+static jack_client_t *client = NULL;
+static int active = 0;
+static float bpm = 120.0f;
+static int loop_length = 8;          /* beats */
+static int current_beat = 0;
+static float *buffer = NULL;
+static int buffer_size = 0;
+
+/* ---------------------------------------------------------------------------
+ *  drawing helpers (stubs for microui)
+ * ------------------------------------------------------------------------- */
+static void draw_frame(mu_Context *ctx, mu_Rect rect, int colorid)
+{
+    /* stub: we rely on ncurses for actual rendering */
+    (void)ctx;
+    (void)rect;
+    (void)colorid;
+}
+
+/* ---------------------------------------------------------------------------
+ *  GUI update
+ * ------------------------------------------------------------------------- */
+static void gui_update(void)
+{
+    mu_begin(ctx);
+
+    /* main window */
+    if (mu_begin_window(ctx, "Jack Looper", mu_rect(10, 10, 400, 300))) {
+        /* transport controls */
+        mu_layout_row(ctx, 3, (int[]) { 80, 80, 80 }, 0);
+        if (mu_button(ctx, active ? "Stop" : "Play")) {
+            active = !active;
+            if (active) {
+                engine_start(client);
+            } else {
+                engine_stop(client);
+            }
+        }
+        if (mu_button(ctx, "Reset")) {
+            current_beat = 0;
+        }
+        if (mu_button(ctx, "Quit")) {
+            running = 0;
+        }
+
+        /* BPM slider */
+        mu_layout_row(ctx, 2, (int[]) { 60, -1 }, 0);
+        mu_label(ctx, "BPM:");
+        if (mu_slider(ctx, &bpm, 20.0f, 300.0f, 0, "%.0f", 0)) {
+            engine_set_bpm(client, bpm);
+        }
+
+        /* loop length */
+        mu_layout_row(ctx, 2, (int[]) { 60, -1 }, 0);
+        mu_label(ctx, "Length:");
+        if (mu_slider(ctx, (float*)&loop_length, 1.0f, 64.0f, 0, "%.0f", 0)) {
+            engine_set_loop_length(client, loop_length);
+        }
+
+        /* beat indicator */
+        mu_layout_row(ctx, 1, (int[]) { -1 }, 0);
+        {
+            char buf[64];
+            snprintf(buf, sizeof(buf), "Beat: %d / %d", current_beat + 1, loop_length);
+            mu_label(ctx, buf);
+        }
+
+        /* progress bar */
+        mu_layout_row(ctx, 1, (int[]) { -1 }, 0);
+        {
+            float progress = (loop_length > 0) ? (float)current_beat / (float)loop_length : 0.0f;
+            mu_Rect r = mu_layout_next(ctx);
+            mu_draw_control_frame(ctx, mu_get_id(ctx, &progress, sizeof(progress)), r, MU_COLOR_BASE, 0);
+            if (progress > 0.0f) {
+                mu_Rect fill = r;
+                fill.w = (int)(r.w * progress);
+                mu_draw_rect(ctx, fill, mu_color(100, 200, 100, 255));
+            }
+        }
+
+        mu_end_window(ctx);
+    }
+
+    mu_end(ctx);
+}
+
+/* ---------------------------------------------------------------------------
+ *  main loop
+ * ------------------------------------------------------------------------- */
+int gui_main(jack_client_t *jack_client, float *audio_buffer, int buf_size)
+{
+    client = jack_client;
+    buffer = audio_buffer;
+    buffer_size = buf_size;
+
+    /* initialise microui */
+    ctx = malloc(sizeof(mu_Context));
+    if (!ctx) return -1;
+    mu_init(ctx);
+    ctx->text_width = text_width;
+    ctx->text_height = text_height;
+    ctx->draw_frame = draw_frame;
+
+    /* ncurses setup */
+    initscr();
+    cbreak();
+    noecho();
+    keypad(stdscr, TRUE);
+    nodelay(stdscr, TRUE);
+    curs_set(0);
+
+    /* main loop */
+    while (running) {
+        /* handle input */
+        int ch = getch();
+        if (ch != ERR) {
+            switch (ch) {
+                case 'q':
+                case 'Q':
+                    running = 0;
+                    break;
+                case ' ':
+                    active = !active;
+                    if (active) {
+                        engine_start(client);
+                    } else {
+                        engine_stop(client);
+                    }
+                    break;
+                case KEY_UP:
+                    bpm = fminf(bpm + 5.0f, 300.0f);
+                    engine_set_bpm(client, bpm);
+                    break;
+                case KEY_DOWN:
+                    bpm = fmaxf(bpm - 5.0f, 20.0f);
+                    engine_set_bpm(client, bpm);
+                    break;
+                case KEY_LEFT:
+                    loop_length = (loop_length > 1) ? loop_length - 1 : 1;
+                    engine_set_loop_length(client, loop_length);
+                    break;
+                case KEY_RIGHT:
+                    loop_length = (loop_length < 64) ? loop_length + 1 : 64;
+                    engine_set_loop_length(client, loop_length);
+                    break;
+                default:
+                    break;
+            }
+        }
+
+        /* update engine state */
+        current_beat = engine_get_current_beat(client);
+
+        /* render GUI */
+        gui_update();
+
+        /* draw commands */
+        mu_Command *cmd = NULL;
+        while (mu_next_command(ctx, &cmd)) {
+            if (cmd->type == MU_COMMAND_TEXT) {
+                mvprintw(cmd->text.pos.y / 18, cmd->text.pos.x / 8, "%.*s",
+                         cmd->text.len, cmd->text.text);
+            }
+            if (cmd->type == MU_COMMAND_RECT) {
+                /* simple rectangle rendering using ncurses */
+                int x = cmd->rect.rect.x / 8;
+                int y = cmd->rect.rect.y / 18;
+                int w = cmd->rect.rect.w / 8;
+                int h = cmd->rect.rect.h / 18;
+                for (int i = 0; i < h && y + i < LINES; i++) {
+                    mvhline(y + i, x, ' ', w);
+                }
+            }
+        }
+
+        refresh();
+        usleep(16666); /* ~60 fps */
+    }
+
+    /* cleanup */
+    endwin();
+    free(ctx);
+    return 0;
+}
--- a/gui.h
+++ b/gui.h
@@ -0,0 +1,8 @@
+#ifndef GUI_H
+#define GUI_H
+
+#include <jack/jack.h>
+
+int gui_main(jack_client_t *client, float *audio_buffer, int buf_size);
+
+#endif /* GUI_H */
--- a/main.c
+++ b/main.c
@@ -84,3 +84,47 @@ int main(int argc, char *argv[]) {
    
    return 0;
 }
+#include <stdio.h>
+#include <stdlib.h>
+#include <jack/jack.h>
+#include "engine.h"
+#include "tui.h"
+
+int main(void)
+{
+    jack_client_t *client;
+    const char *client_name = "jack_looper";
+    jack_options_t options = JackNullOption;
+    jack_status_t status;
+
+    client = jack_client_open(client_name, options, &status);
+    if (client == NULL) {
+        fprintf(stderr, "jack_client_open() failed, status = 0x%2.0x\n", status);
+        if (status & JackServerFailed) {
+            fprintf(stderr, "Unable to connect to JACK server\n");
+        }
+        return 1;
+    }
+
+    float *buffer = calloc(4096, sizeof(float));
+    if (!buffer) {
+        fprintf(stderr, "Failed to allocate audio buffer\n");
+        jack_client_close(client);
+        return 1;
+    }
+
+    if (engine_init(client, buffer, 4096) != 0) {
+        fprintf(stderr, "Failed to initialize engine\n");
+        free(buffer);
+        jack_client_close(client);
+        return 1;
+    }
+
+    int ret = tui_main(client, buffer, 4096);
+
+    engine_cleanup(client);
+    free(buffer);
+    jack_client_close(client);
+
+    return ret;
+}
--- a/16
+++ b/16
@@ -2,7 +2,7 @@ CC = gcc
 CFLAGS = -Wall -Wextra -std=c99 -D_POSIX_C_SOURCE=200809L
 LDFLAGS = -ljack -lm -lncurses

-all: jack-looper test_engine test_tui
+all: jack-looper test_engine test_tui test_gui

 jack-looper: main.o engine.o tui.o
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
@@ -13,6 +13,9 @@ test_engine: test_engine.o engine.o
 test_tui: test_tui.o engine.o
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)

+test_gui: test_gui.o engine.o gui.o
+	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
+
 main.o: main.c engine.h tui.h
 	$(CC) $(CFLAGS) -c -o $@ $<

@@ -22,17 +25,24 @@ engine.o: engine.c engine.h
 tui.o: tui.c tui.h engine.h
 	$(CC) $(CFLAGS) -c -o $@ $<

+gui.o: gui.c gui.h engine.h microui.h
+	$(CC) $(CFLAGS) -c -o $@ $<
+
 test_engine.o: test_engine.c engine.h
 	$(CC) $(CFLAGS) -c -o $@ $<

 test_tui.o: test_tui.c engine.h tui.h
 	$(CC) $(CFLAGS) -c -o $@ $<

+test_gui.o: test_gui.c engine.h gui.h
+	$(CC) $(CFLAGS) -c -o $@ $<
+
 .PHONY: all clean test

 clean:
-	rm -f *.o jack-looper test_engine test_tui
+	rm -f *.o jack-looper test_engine test_tui test_gui

-test: test_engine test_tui
+test: test_engine test_tui test_gui
 	./test_engine
 	./test_tui
+	./test_gui
--- a/test_gui.c
+++ b/test_gui.c
@@ -0,0 +1,53 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <jack/jack.h>
+#include "engine.h"
+#include "gui.h"
+
+static jack_client_t *client = NULL;
+static float *buffer = NULL;
+static int buffer_size = 0;
+
+int main(void)
+{
+    /* create JACK client */
+    const char *client_name = "jack_looper_gui_test";
+    jack_options_t options = JackNullOption;
+    jack_status_t status;
+
+    client = jack_client_open(client_name, options, &status);
+    if (client == NULL) {
+        fprintf(stderr, "jack_client_open() failed, status = 0x%2.0x\n", status);
+        if (status & JackServerFailed) {
+            fprintf(stderr, "Unable to connect to JACK server\n");
+        }
+        return 1;
+    }
+
+    /* allocate audio buffer */
+    buffer_size = 4096;
+    buffer = calloc(buffer_size, sizeof(float));
+    if (!buffer) {
+        fprintf(stderr, "Failed to allocate audio buffer\n");
+        jack_client_close(client);
+        return 1;
+    }
+
+    /* initialize engine */
+    if (engine_init(client, buffer, buffer_size) != 0) {
+        fprintf(stderr, "Failed to initialize engine\n");
+        free(buffer);
+        jack_client_close(client);
+        return 1;
+    }
+
+    /* run GUI */
+    int ret = gui_main(client, buffer, buffer_size);
+
+    /* cleanup */
+    engine_cleanup(client);
+    free(buffer);
+    jack_client_close(client);
+
+    return ret;
+}