path: root/src/main.c

/*
Copyright (c) 2023 Bad Diode

Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE.
*/

// TODO: A list of features I would like to get to implement in the near future.
//
// UI tweaks.
//  - Notification support for feedback when doing some operations
//    (copying/pasting)
//  - Animations for cursor movement/current step highlight. (A fade out maybe?)
//  - Theming support, with a number of pre-configured themes and custom colors.
//  - Add panning support. We could send ch1-3 to the left and ch4 to the right
//    to act as metronome and achieve analog sync.
//
// Quality of life improvements.
//  + Add a settings page to change some configuration parameters.
//  - Change the cursor, the line is difficult to see.
//  - When not on play mode, adjusting a note or a parameter triggers the sound.
//    This could get annoying, so maybe it should be a configuration option to
//    enable it?
//  - Pattern chaining for more than 1 queue and/or song mode.
//  - Undo/Redo.
//  - Select + up/down to queue the next pattern as we move to it?
//
//  Advanced
//  + Sync via CV by using the link cable.
//  - Audio sync by panning left the sound and using right as a click (or
//    viceversa, needs to check the standard.)
//  - Sync via MIDI via arduinoboy or something similar.
//  - Add an FM channel using Direct Sound.
//  - Per trig note probability.
//  - Add an envelope to ch3, would need to work with a timer in order to make
//    it work I think.
//  - Allow "marking" several trigs to be able to copy/paste them and/or adjust
//    their parameters.
//
//  Bugfixes
//  - Sound can get hung up sometimes, but I can't reproduce when this happens.
//    Not sure if this is an emulator thing or happens also in hardware.
//  - Cursor can stay in position instead of dissapering, again I can't
//    reproduce this right now, just happened randomly. Needs investigation.
//  + Pattern chaining seems off, it plays the first note of the pattern before
//    switching
//  + Memory corruption when trying to load a save file. Regression due to
//  removal of filesystem.c
//

#include "gba/gba.h"

#include "renderer_m0.c"
#include "sequencer.c"

#define PROF_ENABLE 0
#include "profiling.c"

void
render_sequencer(void) {
    PROF(draw_rect(0, 0, SCREEN_WIDTH - 1, SCREEN_HEIGHT - 1, 1), clear_cycles);
    if (redraw_trigs) {
        PROF(draw_triggers(), draw_trigs_cycles);
        redraw_trigs = false;
    }
    if (redraw_channels) {
        PROF(draw_channels(), draw_btn_cycles);
        redraw_channels = false;
    }
    if (redraw_pattern_buttons) {
        PROF(draw_pattern_buttons(), draw_btn_cycles);
        redraw_pattern_buttons = false;
    }
    if (redraw_bank_buttons) {
        PROF(draw_bank_buttons(), draw_btn_cycles);
        redraw_bank_buttons = false;
    }
    if (redraw_bpm) {
        PROF(draw_bpm(), draw_btn_cycles);
        redraw_bpm = false;
    }
    if (redraw_play_pause) {
        PROF(draw_play(), draw_btn_cycles);
        PROF(draw_stop(), draw_btn_cycles);
        redraw_play_pause = false;
    }
    if (redraw_piano_note) {
        PROF(draw_piano_notes(), draw_piano_cycles);
        redraw_piano_note = false;
    }
    if (redraw_params) {
        PROF(draw_parameters(), draw_param_cycles);
        redraw_params = false;
    }
    PROF(draw_cursors(), draw_cursor_cycles);
}

bool clear_screen = false;

typedef enum Scene {
    SCENE_SEQUENCER = 0,
    SCENE_SETTINGS,
} Scene;

static scene = SCENE_SETTINGS;
static next_scene = SCENE_SETTINGS;

typedef enum SyncSetting {
    SYNC_NONE = 0,
    SYNC_OUT_LINK_16,
    SYNC_OUT_LINK_8,
    SYNC_OUT_LINK_4,
    SYNC_NUM,
} SyncSetting;

char * sync_setting_str[] = {
    "NONE",
    "LINK OUT (16)",
    "LINK OUT (8)",
    "LINK OUT (4)",
};

typedef enum  ThemeSetting {
    THEME_DEFAULT = 0,
} ThemeSetting;

char * theme_setting_str[] = {
    "DEFAULT",
};

typedef enum  CursorSetting {
    CURSOR_DEFAULT = 0,
} CursorSetting;

char * cursor_setting_str[] = {
    "LINE",
};

typedef struct Settings {
    SyncSetting sync;
    ThemeSetting theme;
    CursorSetting cursor;
} Settings;

static Settings settings = {0};
static settings_cursor_loc = 0;

void
draw_settings_cursor(void) {
    int x = 6;
    int y = 17 + settings_cursor_loc * 12;
    draw_line(x + 1, y + 3, x + 1, y + 7, COL_CYAN);
    draw_line(x + 2, y + 4, x + 2, y + 6, COL_CYAN);
    draw_line(x + 3, y + 5, x + 3, y + 5, COL_CYAN);
}

void
render_settings(void) {
    PROF(draw_rect(0, 0, SCREEN_WIDTH - 1, SCREEN_HEIGHT - 1, 1), clear_cycles);
    txt_drawf_small("settings", 11, 5, COL_FG)
    txt_printf("\n\n\n");
    txt_printf("  SYNC:   %s\n\n", sync_setting_str[settings.sync]);
    txt_printf("  THEME:  %s\n\n", theme_setting_str[settings.theme]);
    txt_printf("  CURSOR: %s\n\n", cursor_setting_str[settings.cursor]);
    txt_render();
    txt_clear();
    draw_settings_cursor();
}

#define N_SETTINGS 3

void
handle_settings_input(void) {
    if (key_tap(KEY_DOWN)) {
        if (settings_cursor_loc == (N_SETTINGS - 1)) {
            settings_cursor_loc = 0;
        } else {
            settings_cursor_loc++;
        }
        clear_screen = true;
    }
    if (key_tap(KEY_UP)) {
        if (settings_cursor_loc == 0) {
            settings_cursor_loc = N_SETTINGS - 1;
        } else {
            settings_cursor_loc--;
        }
        clear_screen = true;
    }
    if (key_tap(KEY_R)) {
        switch (settings_cursor_loc) {
            case 0: {
                if ((settings.sync + 1) >= SYNC_NUM) {
                    settings.sync = 0;
                } else {
                    settings.sync++;
                }
            } break;
        }
        clear_screen = true;
    }
    if (key_tap(KEY_L)) {
        switch (settings_cursor_loc) {
            case 0: {
                if (settings.sync == 0) {
                    settings.sync = SYNC_NUM - 1;
                } else {
                    settings.sync--;
                }
            } break;
        }
        clear_screen = true;
    }
    if (key_tap(KEY_B)) {
        next_scene = SCENE_SEQUENCER;
    }
}

void
render(void) {
    if (clear_screen) {
        screen_fill(COL_BG);
        clear_screen = false;
    }
    switch (scene) {
        case SCENE_SETTINGS: {
            render_settings();
        } break;
        case SCENE_SEQUENCER: {
            render_sequencer();
        } break;
    }
}

void
handle_input(void) {
    switch (scene) {
        case SCENE_SETTINGS: {
            handle_settings_input();
        } break;
        case SCENE_SEQUENCER: {
            handle_sequencer_input();
        } break;
    }
}

void
update(void) {
    if (next_scene != scene) {
        scene = next_scene;
        clear_screen = true;
    }
    last_trig_loc = trig_selection_loc;
    last_channel_loc = channel_selection_loc;
    last_pattern_loc = pattern_selection_loc;
    last_right_col_loc = right_col_selection_loc;
    if (update_bpm) {
        set_time(patterns[current_pattern].bpm);
        update_bpm = false;
    }
}

int
main(void) {
    // Adjust system wait times.
    SYSTEM_WAIT = SYSTEM_WAIT_CARTRIDGE;

    // Initialize renderer.
    renderer_init();

    // Register interrupts.
    irq_init();
    irs_set(IRQ_VBLANK, irs_stub);

    // Initialize sequencer.
    sequencer_init();
    txt_spacing(6);

    // Main loop.
    while (true) {
        poll_keys();
        bios_vblank_wait();
        PROF_SHOW();
        FRAME_START();
        PROF(flip_buffer(), flip_cycles);
        PROF(update(), update_cycles);
        PROF(handle_input(), input_cycles);
        PROF(render(), render_cycles);
        FRAME_END();
    }

    return 0;
}