ESP32_Serial_Swiss_Army_Knife/src/local_boot_animation.c

/* SPDX-License-Identifier: GPL-3.0-only */
/* Compact monochrome derivative of images/logo.png for the 128x48 content panel. */

#include "local_boot_animation.h"

#include <stdbool.h>
#include <stdint.h>

#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "local_display.h"

#define BOOT_ANIMATION_FRAMES 20U
#define BOOT_ANIMATION_FRAME_MS 250U
#define BOOT_ANIMATION_NAME_SPEED 16U

static const char s_device_name[] = "ESP32 SERIAL SWISS ARMY KNIFE";

static void pixel(int x, int y)
{
    if (x >= 0 && x < (int)LOCAL_DISPLAY_WIDTH &&
        y >= 0 && y < (int)LOCAL_DISPLAY_CONTENT_HEIGHT) {
        local_display_frame_set_pixel(LOCAL_DISPLAY_PANEL_CONTENT, (uint8_t)x,
                                      (uint8_t)y, true);
    }
}

static void line(int x0, int y0, int x1, int y1)
{
    int dx = x1 >= x0 ? x1 - x0 : x0 - x1;
    int sx = x0 < x1 ? 1 : -1;
    int dy = y1 >= y0 ? y0 - y1 : y1 - y0;
    int sy = y0 < y1 ? 1 : -1;
    int error = dx + dy;

    for (;;) {
        pixel(x0, y0);
        if (x0 == x1 && y0 == y1) {
            return;
        }
        int twice_error = 2 * error;
        if (twice_error >= dy) {
            error += dy;
            x0 += sx;
        }
        if (twice_error <= dx) {
            error += dx;
            y0 += sy;
        }
    }
}

static void rectangle(int x, int y, int width, int height)
{
    line(x, y, x + width - 1, y);
    line(x, y, x, y + height - 1);
    line(x + width - 1, y, x + width - 1, y + height - 1);
    line(x, y + height - 1, x + width - 1, y + height - 1);
}

static void draw_serial_connector(void)
{
    rectangle(2, 8, 16, 10);
    rectangle(4, 10, 12, 6);
    for (int column = 0; column < 5; ++column) {
        pixel(6 + column * 2, 12);
        pixel(6 + column * 2, 14);
    }
    line(18, 13, 30, 22);
    line(18, 16, 28, 25);
}

static void draw_usb_connector(void)
{
    rectangle(2, 31, 14, 11);
    rectangle(4, 33, 10, 7);
    line(16, 35, 29, 30);
    line(16, 39, 30, 34);
    pixel(7, 35);
    pixel(10, 38);
}

static void draw_terminal(bool cursor_on)
{
    rectangle(28, 21, 42, 22);
    rectangle(30, 23, 38, 18);
    /* Keep the prompt upright even though the source logo is reoriented. */
    line(38, 28, 45, 33);
    line(45, 33, 38, 38);
    if (cursor_on) {
        line(51, 37, 59, 37);
    }
    line(31, 27, 31, 39);
    line(67, 27, 67, 39);
    line(34, 22, 34, 20);
    line(63, 22, 63, 20);
}

static void draw_board(void)
{
    rectangle(72, 7, 28, 36);
    rectangle(78, 14, 16, 17);
    for (int row = 0; row < 5; ++row) {
        pixel(74, 11 + row * 6);
        pixel(76, 11 + row * 6);
        pixel(96, 11 + row * 6);
        pixel(98, 11 + row * 6);
    }
    for (int column = 0; column < 6; ++column) {
        pixel(79 + column * 3, 35);
        pixel(79 + column * 3, 38);
    }
    line(70, 28, 72, 28);
    line(70, 34, 72, 34);
}

static void draw_wifi(uint8_t frame)
{
    bool outer = (frame % 2U) == 0U;
    if (outer) {
        line(103, 8, 109, 3);
        line(109, 3, 115, 8);
    }
    line(105, 12, 109, 8);
    line(109, 8, 113, 12);
    line(107, 16, 109, 14);
    line(109, 14, 111, 16);
    pixel(109, 19);
}

static void draw_logo(uint8_t frame)
{
    draw_serial_connector();
    draw_usb_connector();
    draw_terminal((frame % 2U) == 0U);
    draw_board();
    draw_wifi(frame);
}

static void draw_scrolling_name(uint8_t frame)
{
    int text_width = ((int)sizeof(s_device_name) - 1) * 6;
    int x = (int)LOCAL_DISPLAY_WIDTH - (int)frame * BOOT_ANIMATION_NAME_SPEED;
    if (x < -text_width) {
        x += text_width + (int)LOCAL_DISPLAY_WIDTH;
    }
    const char *text = s_device_name;
    while (x < 0 && *text != '\0') {
        x += 6;
        ++text;
    }
    if (x < (int)LOCAL_DISPLAY_WIDTH && *text != '\0') {
        local_display_frame_draw_text(LOCAL_DISPLAY_PANEL_STATUS, (uint8_t)x, 4U, text);
    }
}

esp_err_t local_boot_animation_play(void)
{
    for (uint8_t frame = 0U; frame < BOOT_ANIMATION_FRAMES; ++frame) {
        esp_err_t error = local_display_frame_begin();
        if (error != ESP_OK) {
            return error;
        }
        local_display_frame_clear_all();
        draw_scrolling_name(frame);
        draw_logo(frame);
        error = local_display_frame_end();
        if (error != ESP_OK) {
            return error;
        }
        vTaskDelay(pdMS_TO_TICKS(BOOT_ANIMATION_FRAME_MS));
    }
    return ESP_OK;
}