ESP32_Serial_Swiss_Army_Knife/src/local_display.c

/* SPDX-License-Identifier: GPL-3.0-only */
/* Bounded SSD1315-compatible OLED service with separate physical panels. */

#include "local_display.h"

#include <string.h>

#include "board_pins.h"
#include "driver/i2c_master.h"
#include "esp_timer.h"
#include "freertos/FreeRTOS.h"
#include "freertos/semphr.h"
#include "freertos/task.h"

#define LOCAL_DISPLAY_PAGE_COUNT (LOCAL_DISPLAY_HEIGHT / 8U)
#define LOCAL_DISPLAY_FRAMEBUFFER_SIZE (LOCAL_DISPLAY_WIDTH * LOCAL_DISPLAY_PAGE_COUNT)
#define LOCAL_DISPLAY_I2C_SPEED_HZ 100000U
#define LOCAL_DISPLAY_I2C_TIMEOUT_MS 250U
#define LOCAL_DISPLAY_PROBE_TIMEOUT_MS 50U
#define LOCAL_DISPLAY_SCAN_TIMEOUT_MS 10U
#define LOCAL_DISPLAY_LOCK_TIMEOUT_MS 3000U
#define LOCAL_DISPLAY_DEFAULT_CONTRAST 127U
#define LOCAL_DISPLAY_COMMAND_CAPACITY 32U
#define LOCAL_DISPLAY_DATA_CHUNK_SIZE 128U
#define LOCAL_DISPLAY_FLUSH_BUDGET_US (500LL * 1000LL)

static const uint8_t s_expected_addresses[] = {0x3cU, 0x3dU};

typedef struct {
    char character;
    uint8_t columns[5];
} glyph_t;

/* Compact project-owned 5x7 ASCII subset with distinct upper/lower-case glyphs. */
static const glyph_t s_glyphs[] = {
    {' ', {0x00, 0x00, 0x00, 0x00, 0x00}},
    {'!', {0x00, 0x00, 0x5f, 0x00, 0x00}},
    {'-', {0x08, 0x08, 0x08, 0x08, 0x08}},
    {'.', {0x00, 0x60, 0x60, 0x00, 0x00}},
    {'/', {0x20, 0x10, 0x08, 0x04, 0x02}},
    {':', {0x00, 0x36, 0x36, 0x00, 0x00}},
    {'>', {0x00, 0x41, 0x22, 0x14, 0x08}},
    {'?', {0x02, 0x01, 0x51, 0x09, 0x06}},
    {'_', {0x40, 0x40, 0x40, 0x40, 0x40}},
    {'0', {0x3e, 0x51, 0x49, 0x45, 0x3e}},
    {'1', {0x00, 0x42, 0x7f, 0x40, 0x00}},
    {'2', {0x42, 0x61, 0x51, 0x49, 0x46}},
    {'3', {0x21, 0x41, 0x45, 0x4b, 0x31}},
    {'4', {0x18, 0x14, 0x12, 0x7f, 0x10}},
    {'5', {0x27, 0x45, 0x45, 0x45, 0x39}},
    {'6', {0x3c, 0x4a, 0x49, 0x49, 0x30}},
    {'7', {0x01, 0x71, 0x09, 0x05, 0x03}},
    {'8', {0x36, 0x49, 0x49, 0x49, 0x36}},
    {'9', {0x06, 0x49, 0x49, 0x29, 0x1e}},
    {'A', {0x7e, 0x11, 0x11, 0x11, 0x7e}},
    {'B', {0x7f, 0x49, 0x49, 0x49, 0x36}},
    {'C', {0x3e, 0x41, 0x41, 0x41, 0x22}},
    {'D', {0x7f, 0x41, 0x41, 0x22, 0x1c}},
    {'E', {0x7f, 0x49, 0x49, 0x49, 0x41}},
    {'F', {0x7f, 0x09, 0x09, 0x09, 0x01}},
    {'G', {0x3e, 0x41, 0x49, 0x49, 0x7a}},
    {'H', {0x7f, 0x08, 0x08, 0x08, 0x7f}},
    {'I', {0x00, 0x41, 0x7f, 0x41, 0x00}},
    {'J', {0x20, 0x40, 0x41, 0x3f, 0x01}},
    {'K', {0x7f, 0x08, 0x14, 0x22, 0x41}},
    {'L', {0x7f, 0x40, 0x40, 0x40, 0x40}},
    {'M', {0x7f, 0x02, 0x0c, 0x02, 0x7f}},
    {'N', {0x7f, 0x04, 0x08, 0x10, 0x7f}},
    {'O', {0x3e, 0x41, 0x41, 0x41, 0x3e}},
    {'P', {0x7f, 0x09, 0x09, 0x09, 0x06}},
    {'Q', {0x3e, 0x41, 0x51, 0x21, 0x5e}},
    {'R', {0x7f, 0x09, 0x19, 0x29, 0x46}},
    {'S', {0x46, 0x49, 0x49, 0x49, 0x31}},
    {'T', {0x01, 0x01, 0x7f, 0x01, 0x01}},
    {'U', {0x3f, 0x40, 0x40, 0x40, 0x3f}},
    {'V', {0x1f, 0x20, 0x40, 0x20, 0x1f}},
    {'W', {0x7f, 0x20, 0x18, 0x20, 0x7f}},
    {'X', {0x63, 0x14, 0x08, 0x14, 0x63}},
    {'Y', {0x03, 0x04, 0x78, 0x04, 0x03}},
    {'Z', {0x61, 0x51, 0x49, 0x45, 0x43}},
    {'a', {0x20, 0x54, 0x54, 0x54, 0x78}},
    {'b', {0x7f, 0x48, 0x44, 0x44, 0x38}},
    {'c', {0x38, 0x44, 0x44, 0x44, 0x20}},
    {'d', {0x38, 0x44, 0x44, 0x48, 0x7f}},
    {'e', {0x38, 0x54, 0x54, 0x54, 0x18}},
    {'f', {0x08, 0x7e, 0x09, 0x01, 0x02}},
    {'g', {0x0c, 0x52, 0x52, 0x52, 0x3e}},
    {'h', {0x7f, 0x08, 0x04, 0x04, 0x78}},
    {'i', {0x00, 0x44, 0x7d, 0x40, 0x00}},
    {'j', {0x20, 0x40, 0x44, 0x3d, 0x00}},
    {'k', {0x7f, 0x10, 0x28, 0x44, 0x00}},
    {'l', {0x00, 0x41, 0x7f, 0x40, 0x00}},
    {'m', {0x7c, 0x04, 0x18, 0x04, 0x78}},
    {'n', {0x7c, 0x08, 0x04, 0x04, 0x78}},
    {'o', {0x38, 0x44, 0x44, 0x44, 0x38}},
    {'p', {0x7c, 0x14, 0x14, 0x14, 0x08}},
    {'q', {0x08, 0x14, 0x14, 0x18, 0x7c}},
    {'r', {0x7c, 0x08, 0x04, 0x04, 0x08}},
    {'s', {0x48, 0x54, 0x54, 0x54, 0x20}},
    {'t', {0x04, 0x3f, 0x44, 0x40, 0x20}},
    {'u', {0x3c, 0x40, 0x40, 0x20, 0x7c}},
    {'v', {0x1c, 0x20, 0x40, 0x20, 0x1c}},
    {'w', {0x3c, 0x40, 0x30, 0x40, 0x3c}},
    {'x', {0x44, 0x28, 0x10, 0x28, 0x44}},
    {'y', {0x0c, 0x50, 0x50, 0x50, 0x3c}},
    {'z', {0x44, 0x64, 0x54, 0x4c, 0x44}},
};

static i2c_master_bus_handle_t s_bus;
static i2c_master_dev_handle_t s_device;
static StaticSemaphore_t s_mutex_storage;
static SemaphoreHandle_t s_mutex;
static uint8_t s_framebuffer[LOCAL_DISPLAY_FRAMEBUFFER_SIZE];
static bool s_bus_ready;
static bool s_initialized;
static bool s_frame_active;
static TaskHandle_t s_frame_owner;
static uint8_t s_address;
static uint8_t s_contrast = LOCAL_DISPLAY_DEFAULT_CONTRAST;
static bool s_inverted;
static uint8_t s_dirty_pages;
static esp_err_t s_last_error = ESP_ERR_INVALID_STATE;

static TickType_t milliseconds_to_ticks(uint32_t milliseconds)
{
    TickType_t ticks = pdMS_TO_TICKS(milliseconds);
    return (milliseconds > 0U && ticks == 0U) ? 1U : ticks;
}

static esp_err_t take_lock(void)
{
    if (s_mutex == NULL) {
        return ESP_ERR_INVALID_STATE;
    }
    return xSemaphoreTake(s_mutex, milliseconds_to_ticks(LOCAL_DISPLAY_LOCK_TIMEOUT_MS)) == pdTRUE
               ? ESP_OK
               : ESP_ERR_TIMEOUT;
}

static void give_lock(void)
{
    if (s_mutex != NULL) {
        (void)xSemaphoreGive(s_mutex);
    }
}

static void set_last_error(esp_err_t error)
{
    s_last_error = error;
}

static esp_err_t send_commands_locked(const uint8_t *commands, size_t count)
{
    if (!s_initialized || s_device == NULL || commands == NULL || count == 0U ||
        count > LOCAL_DISPLAY_COMMAND_CAPACITY) {
        return ESP_ERR_INVALID_STATE;
    }

    uint8_t transfer[LOCAL_DISPLAY_COMMAND_CAPACITY + 1U];
    transfer[0] = 0x00U;
    memcpy(&transfer[1], commands, count);
    return i2c_master_transmit(s_device, transfer, count + 1U,
                               LOCAL_DISPLAY_I2C_TIMEOUT_MS);
}

static esp_err_t send_command_locked(uint8_t command)
{
    return send_commands_locked(&command, 1U);
}

static esp_err_t flush_dirty_locked(void)
{
    if (!s_initialized || s_device == NULL) {
        return ESP_ERR_INVALID_STATE;
    }

    int64_t started = esp_timer_get_time();
    uint8_t transfer[LOCAL_DISPLAY_DATA_CHUNK_SIZE + 1U];
    transfer[0] = 0x40U;
    for (uint8_t page = 0U; page < LOCAL_DISPLAY_PAGE_COUNT; ++page) {
        uint8_t page_mask = (uint8_t)(1U << page);
        if ((s_dirty_pages & page_mask) == 0U) {
            continue;
        }
        if ((esp_timer_get_time() - started) >= LOCAL_DISPLAY_FLUSH_BUDGET_US) {
            return ESP_ERR_TIMEOUT;
        }

        const uint8_t commands[] = {
            0x21U, 0x00U, (uint8_t)(LOCAL_DISPLAY_WIDTH - 1U),
            0x22U, page, page,
        };
        esp_err_t error = send_commands_locked(commands, sizeof(commands));
        if (error != ESP_OK) {
            return error;
        }
        if ((esp_timer_get_time() - started) >= LOCAL_DISPLAY_FLUSH_BUDGET_US) {
            return ESP_ERR_TIMEOUT;
        }
        memcpy(&transfer[1], &s_framebuffer[(size_t)page * LOCAL_DISPLAY_WIDTH],
               LOCAL_DISPLAY_WIDTH);
        error = i2c_master_transmit(s_device, transfer, sizeof(transfer),
                                    LOCAL_DISPLAY_I2C_TIMEOUT_MS);
        if (error != ESP_OK) {
            return error;
        }
        s_dirty_pages &= (uint8_t)~page_mask;
    }
    return ESP_OK;
}

static void set_pixel_raw(uint8_t x, uint8_t y, bool on)
{
    if (x >= LOCAL_DISPLAY_WIDTH || y >= LOCAL_DISPLAY_HEIGHT) {
        return;
    }
    size_t index = (size_t)(y / 8U) * LOCAL_DISPLAY_WIDTH + x;
    uint8_t mask = (uint8_t)(1U << (y & 7U));
    uint8_t before = s_framebuffer[index];
    if (on) {
        s_framebuffer[index] |= mask;
    } else {
        s_framebuffer[index] &= (uint8_t)~mask;
    }
    if (before != s_framebuffer[index]) {
        s_dirty_pages |= (uint8_t)(1U << (y / 8U));
    }
}

static bool panel_geometry(local_display_panel_t panel, uint8_t *origin_y, uint8_t *height)
{
    if (origin_y == NULL || height == NULL) {
        return false;
    }
    switch (panel) {
    case LOCAL_DISPLAY_PANEL_STATUS:
        *origin_y = 0U;
        *height = LOCAL_DISPLAY_STATUS_HEIGHT;
        return true;
    case LOCAL_DISPLAY_PANEL_CONTENT:
        *origin_y = LOCAL_DISPLAY_STATUS_HEIGHT;
        *height = LOCAL_DISPLAY_CONTENT_HEIGHT;
        return true;
    default:
        return false;
    }
}

static const glyph_t *find_glyph(char character)
{
    for (size_t index = 0U; index < sizeof(s_glyphs) / sizeof(s_glyphs[0]); ++index) {
        if (s_glyphs[index].character == character) {
            return &s_glyphs[index];
        }
    }
    for (size_t index = 0U; index < sizeof(s_glyphs) / sizeof(s_glyphs[0]); ++index) {
        if (s_glyphs[index].character == '?') {
            return &s_glyphs[index];
        }
    }
    return NULL;
}

static esp_err_t select_device_locked(uint8_t address)
{
    if (address != 0x3cU && address != 0x3dU) {
        return ESP_ERR_INVALID_ARG;
    }
    esp_err_t error = i2c_master_probe(s_bus, address, LOCAL_DISPLAY_PROBE_TIMEOUT_MS);
    if (error != ESP_OK) {
        return error;
    }
    if (s_device != NULL && s_address == address) {
        return ESP_OK;
    }
    if (s_device != NULL) {
        error = i2c_master_bus_rm_device(s_device);
        if (error != ESP_OK) {
            return error;
        }
        s_device = NULL;
        s_initialized = false;
    }

    const i2c_device_config_t config = {
        .dev_addr_length = I2C_ADDR_BIT_LEN_7,
        .device_address = address,
        .scl_speed_hz = LOCAL_DISPLAY_I2C_SPEED_HZ,
    };
    error = i2c_master_bus_add_device(s_bus, &config, &s_device);
    if (error == ESP_OK) {
        s_address = address;
    }
    return error;
}

static esp_err_t initialize_locked(uint8_t address)
{
    s_initialized = false;
    esp_err_t error = select_device_locked(address);
    if (error != ESP_OK) {
        return error;
    }

    const uint8_t commands[] = {
        0xaeU, 0xd5U, 0x80U, 0xa8U, 0x3fU, 0xd3U, 0x00U, 0x40U,
        0x8dU, 0x14U, 0x20U, 0x00U, 0xa1U, 0xc8U, 0xdaU, 0x12U,
        0x81U, LOCAL_DISPLAY_DEFAULT_CONTRAST, 0xd9U, 0xf1U, 0xdbU,
        0x40U, 0xa4U, 0xa6U, 0x2eU,
    };

    /* send_commands_locked requires initialized, so issue the bootstrap directly. */
    uint8_t transfer[sizeof(commands) + 1U];
    transfer[0] = 0x00U;
    memcpy(&transfer[1], commands, sizeof(commands));
    error = i2c_master_transmit(s_device, transfer, sizeof(transfer),
                                LOCAL_DISPLAY_I2C_TIMEOUT_MS);
    if (error != ESP_OK) {
        return error;
    }

    s_initialized = true;
    s_contrast = LOCAL_DISPLAY_DEFAULT_CONTRAST;
    s_inverted = false;
    memset(s_framebuffer, 0, sizeof(s_framebuffer));
    s_dirty_pages = (uint8_t)((1U << LOCAL_DISPLAY_PAGE_COUNT) - 1U);
    error = flush_dirty_locked();
    if (error == ESP_OK) {
        error = send_command_locked(0xafU);
    }
    if (error != ESP_OK) {
        s_initialized = false;
    }
    return error;
}

esp_err_t local_display_init(void)
{
    if (s_bus_ready || s_mutex != NULL) {
        return ESP_ERR_INVALID_STATE;
    }

    s_mutex = xSemaphoreCreateMutexStatic(&s_mutex_storage);
    if (s_mutex == NULL) {
        return ESP_ERR_NO_MEM;
    }

    const i2c_master_bus_config_t config = {
        .i2c_port = LOCAL_UI_I2C_PORT,
        .sda_io_num = LOCAL_UI_DISPLAY_SDA_GPIO,
        .scl_io_num = LOCAL_UI_DISPLAY_SCL_GPIO,
        .clk_source = I2C_CLK_SRC_DEFAULT,
        .glitch_ignore_cnt = 7,
        .flags.enable_internal_pullup = false,
    };
    esp_err_t error = i2c_new_master_bus(&config, &s_bus);
    if (error != ESP_OK) {
        vSemaphoreDelete(s_mutex);
        s_mutex = NULL;
        set_last_error(error);
        return error;
    }
    s_bus_ready = true;
    set_last_error(ESP_OK);
    return ESP_OK;
}

esp_err_t local_display_probe_expected(uint8_t *address_7bit)
{
    if (address_7bit == NULL) {
        return ESP_ERR_INVALID_ARG;
    }
    if (!s_bus_ready) {
        return ESP_ERR_INVALID_STATE;
    }
    esp_err_t error = take_lock();
    if (error != ESP_OK) {
        return error;
    }

    uint8_t found = 0U;
    for (size_t index = 0U; index < sizeof(s_expected_addresses) / sizeof(s_expected_addresses[0]); ++index) {
        uint8_t address = s_expected_addresses[index];
        if (i2c_master_probe(s_bus, address, LOCAL_DISPLAY_PROBE_TIMEOUT_MS) == ESP_OK) {
            if (found == 0U) {
                *address_7bit = address;
            }
            ++found;
        }
    }
    error = found == 0U ? ESP_ERR_NOT_FOUND : ESP_OK;
    set_last_error(error);
    give_lock();
    return error;
}

esp_err_t local_display_start_at(uint8_t address_7bit)
{
    if (!s_bus_ready) {
        return ESP_ERR_INVALID_STATE;
    }
    esp_err_t error = take_lock();
    if (error != ESP_OK) {
        return error;
    }
    error = initialize_locked(address_7bit);
    set_last_error(error);
    give_lock();
    return error;
}

esp_err_t local_display_start(void)
{
    uint8_t address = 0U;
    esp_err_t error = local_display_probe_expected(&address);
    if (error != ESP_OK) {
        return error;
    }
    return local_display_start_at(address);
}

esp_err_t local_display_stop(void)
{
    if (!s_bus_ready) {
        return ESP_ERR_INVALID_STATE;
    }
    esp_err_t error = take_lock();
    if (error != ESP_OK) {
        return error;
    }
    if (!s_initialized) {
        error = ESP_ERR_INVALID_STATE;
    } else {
        error = send_command_locked(0xaeU);
        /* A failed command leaves panel state unknown; force a clean reinit. */
        s_initialized = false;
    }
    set_last_error(error);
    give_lock();
    return error;
}

esp_err_t local_display_get_snapshot(local_display_snapshot_t *snapshot)
{
    if (snapshot == NULL) {
        return ESP_ERR_INVALID_ARG;
    }
    esp_err_t error = take_lock();
    if (error != ESP_OK) {
        return error;
    }
    *snapshot = (local_display_snapshot_t){
        .bus_ready = s_bus_ready,
        .initialized = s_initialized,
        .address_7bit = s_address,
        .contrast = s_contrast,
        .inverted = s_inverted,
        .dirty_page_mask = s_dirty_pages,
        .last_error = s_last_error,
    };
    give_lock();
    return ESP_OK;
}

esp_err_t local_display_scan(local_display_scan_callback_t callback,
                             void *context,
                             size_t *responding_count)
{
    if (!s_bus_ready) {
        return ESP_ERR_INVALID_STATE;
    }
    esp_err_t error = take_lock();
    if (error != ESP_OK) {
        return error;
    }

    uint8_t responses[0x78U - 0x08U];
    size_t found = 0U;
    for (uint16_t address = 0x08U; address <= 0x77U; ++address) {
        if (i2c_master_probe(s_bus, address, LOCAL_DISPLAY_SCAN_TIMEOUT_MS) == ESP_OK) {
            responses[found++] = (uint8_t)address;
        }
        vTaskDelay(1U);
    }
    if (responding_count != NULL) {
        *responding_count = found;
    }
    error = found == 0U ? ESP_ERR_NOT_FOUND : ESP_OK;
    set_last_error(error);
    give_lock();

    /* Callers may safely use the display service from the callback. */
    if (callback != NULL) {
        for (size_t index = 0U; index < found; ++index) {
            callback(responses[index], context);
        }
    }
    return error;
}

esp_err_t local_display_set_contrast(uint8_t contrast)
{
    esp_err_t error = take_lock();
    if (error != ESP_OK) {
        return error;
    }
    const uint8_t commands[] = {0x81U, contrast};
    error = send_commands_locked(commands, sizeof(commands));
    if (error == ESP_OK) {
        s_contrast = contrast;
    } else {
        s_initialized = false;
    }
    set_last_error(error);
    give_lock();
    return error;
}

esp_err_t local_display_set_inverted(bool inverted)
{
    esp_err_t error = take_lock();
    if (error != ESP_OK) {
        return error;
    }
    error = send_command_locked(inverted ? 0xa7U : 0xa6U);
    if (error == ESP_OK) {
        s_inverted = inverted;
    } else {
        s_initialized = false;
    }
    set_last_error(error);
    give_lock();
    return error;
}

esp_err_t local_display_frame_begin(void)
{
    esp_err_t error = take_lock();
    if (error != ESP_OK) {
        return error;
    }
    if (!s_initialized || s_frame_active) {
        give_lock();
        return ESP_ERR_INVALID_STATE;
    }
    s_frame_active = true;
    s_frame_owner = xTaskGetCurrentTaskHandle();
    return ESP_OK;
}

esp_err_t local_display_frame_end(void)
{
    if (!s_frame_active || s_frame_owner != xTaskGetCurrentTaskHandle()) {
        return ESP_ERR_INVALID_STATE;
    }
    esp_err_t error = flush_dirty_locked();
    if (error != ESP_OK) {
        s_initialized = false;
    }
    set_last_error(error);
    s_frame_active = false;
    s_frame_owner = NULL;
    give_lock();
    return error;
}

void local_display_frame_cancel(void)
{
    if (s_frame_active && s_frame_owner == xTaskGetCurrentTaskHandle()) {
        s_frame_active = false;
        s_frame_owner = NULL;
        give_lock();
    }
}

void local_display_frame_clear(local_display_panel_t panel)
{
    if (!s_frame_active || s_frame_owner != xTaskGetCurrentTaskHandle()) {
        return;
    }
    uint8_t origin_y = 0U;
    uint8_t height = 0U;
    if (!panel_geometry(panel, &origin_y, &height)) {
        return;
    }
    for (uint8_t y = origin_y; y < origin_y + height; ++y) {
        for (uint8_t x = 0U; x < LOCAL_DISPLAY_WIDTH; ++x) {
            set_pixel_raw(x, y, false);
        }
    }
}

void local_display_frame_clear_all(void)
{
    if (!s_frame_active || s_frame_owner != xTaskGetCurrentTaskHandle()) {
        return;
    }
    for (size_t index = 0U; index < sizeof(s_framebuffer); ++index) {
        if (s_framebuffer[index] != 0U) {
            s_framebuffer[index] = 0U;
            s_dirty_pages |= (uint8_t)(1U << (index / LOCAL_DISPLAY_WIDTH));
        }
    }
}

void local_display_frame_set_pixel(local_display_panel_t panel,
                                   uint8_t x,
                                   uint8_t y,
                                   bool on)
{
    if (!s_frame_active || s_frame_owner != xTaskGetCurrentTaskHandle()) {
        return;
    }
    uint8_t origin_y = 0U;
    uint8_t height = 0U;
    if (!panel_geometry(panel, &origin_y, &height) || x >= LOCAL_DISPLAY_WIDTH || y >= height) {
        return;
    }
    set_pixel_raw(x, (uint8_t)(origin_y + y), on);
}

void local_display_frame_draw_text(local_display_panel_t panel,
                                   uint8_t x,
                                   uint8_t y,
                                   const char *text)
{
    if (!s_frame_active || s_frame_owner != xTaskGetCurrentTaskHandle() || text == NULL) {
        return;
    }
    uint8_t origin_y = 0U;
    uint8_t height = 0U;
    if (!panel_geometry(panel, &origin_y, &height) || y >= height) {
        return;
    }

    uint16_t cursor_x = x;
    for (const char *character = text; *character != '\0'; ++character) {
        const glyph_t *glyph = find_glyph(*character);
        if (glyph == NULL || cursor_x + 5U > LOCAL_DISPLAY_WIDTH) {
            break;
        }
        for (uint8_t column = 0U; column < 5U; ++column) {
            for (uint8_t row = 0U; row < 7U; ++row) {
                if ((glyph->columns[column] & (uint8_t)(1U << row)) != 0U &&
                    y + row < height) {
                    set_pixel_raw((uint8_t)(cursor_x + column),
                                  (uint8_t)(origin_y + y + row), true);
                }
            }
        }
        cursor_x += 6U;
        if (cursor_x >= LOCAL_DISPLAY_WIDTH) {
            break;
        }
    }
}