Quick Start Guide

This guide will help you get started with ESP Emote GFX in just a few steps.

Installation

Add ESP Emote GFX to your ESP-IDF project by including it as a component. The component is available through the ESP Component Registry.

Basic Setup

  1. Include the main header:

#include "gfx.h"

  1. Initialize the graphics core (no display yet):

gfx_core_config_t gfx_cfg = {
    .fps = 30,
    .task = GFX_EMOTE_INIT_CONFIG()
};
gfx_handle_t handle = gfx_emote_init(&gfx_cfg);
if (handle == NULL) {
    ESP_LOGE(TAG, "Failed to initialize GFX");
    return;
}

  1. Add a display with a flush callback:

void disp_flush_callback(gfx_disp_t *disp, int x1, int y1, int x2, int y2, const void *data)
{
    void *panel = gfx_disp_get_user_data(disp);
    // Send RGB565 data (x1,y1)-(x2,y2) to your panel, e.g. esp_lcd_panel_draw_bitmap(panel, x1, y1, x2, y2, data);
}

gfx_disp_config_t disp_cfg = {
    .h_res = 320,
    .v_res = 240,
    .flush_cb = disp_flush_callback,
    .update_cb = NULL,
    .user_data = your_panel_handle,   // e.g. esp_lcd_panel_handle_t
    .flags = { .swap = true },
    .buffers = { .buf1 = NULL, .buf2 = NULL, .buf_pixels = 320 * 16 },
};
gfx_disp_t *disp = gfx_disp_add(handle, &disp_cfg);
if (disp == NULL) {
    ESP_LOGE(TAG, "Failed to add display");
    gfx_emote_deinit(handle);
    return;
}

  1. (Optional) Register panel IO callback so the framework knows when flush is done:

static bool flush_io_ready(esp_lcd_panel_io_handle_t panel_io, esp_lcd_panel_io_event_data_t *edata, void *user_ctx)
{
    gfx_disp_t *disp = (gfx_disp_t *)user_ctx;
    if (disp) {
        gfx_disp_flush_ready(disp, true);
    }
    return true;
}
const esp_lcd_panel_io_callbacks_t cbs = { .on_color_trans_done = flush_io_ready };
esp_lcd_panel_io_register_event_callbacks(io_handle, &cbs, disp);

  1. (Optional) Add touch input:

void touch_event_cb(gfx_touch_t *touch, const gfx_touch_event_t *event, void *user_data)
{
    // Handle PRESS / MOVE / RELEASE; event->x, event->y, event->hit_obj
}

gfx_touch_config_t touch_cfg = {
    .handle = esp_lcd_touch_handle,   // from your BSP or esp_lcd_touch_new
    .event_cb = touch_event_cb,
    .disp = disp,
    .poll_ms = 50,
    .user_data = NULL,
};
gfx_touch_t *touch = gfx_touch_add(handle, &touch_cfg);

Creating Your First Widget

Widgets are created on a display (gfx_disp_t *), not on the handle.

Creating a Label

gfx_obj_t *label = gfx_label_create(disp);
gfx_label_set_text(label, "Hello, World!");
gfx_obj_set_pos(label, 50, 50);
gfx_label_set_color(label, GFX_COLOR_HEX(0xFF0000));  // Red

Creating an Image

gfx_obj_t *img = gfx_img_create(disp);
extern const gfx_image_dsc_t my_image;
gfx_img_set_src(img, (void *)&my_image);
gfx_obj_set_pos(img, 100, 100);

Creating an Animation

gfx_obj_t *anim = gfx_anim_create(disp);
gfx_anim_set_src(anim, anim_data, anim_size);
gfx_obj_align(anim, GFX_ALIGN_CENTER, 0, 0);
gfx_anim_set_segment(anim, 0, 0xFFFF, 15, true);
gfx_anim_start(anim);

Object touch callback (e.g. drag)

void my_touch_cb(gfx_obj_t *obj, const gfx_touch_event_t *event, void *user_data)
{
    if (event->type == GFX_TOUCH_EVENT_PRESS) { /* ... */ }
    if (event->type == GFX_TOUCH_EVENT_MOVE)  { gfx_obj_set_pos(obj, event->x, event->y); }
}
gfx_obj_set_touch_cb(label, my_touch_cb, NULL);

Thread Safety

When modifying objects from outside the graphics task, use the graphics lock:

gfx_emote_lock(handle);
gfx_label_set_text(label, "Updated text");
gfx_obj_set_pos(img, new_x, new_y);
gfx_emote_unlock(handle);

Complete Example

#include "gfx.h"
#include "esp_log.h"

static const char *TAG = "gfx_example";
static gfx_handle_t gfx_handle = NULL;
static gfx_disp_t *gfx_disp = NULL;

static void disp_flush_callback(gfx_disp_t *disp, int x1, int y1, int x2, int y2, const void *data)
{
    esp_lcd_panel_handle_t panel = (esp_lcd_panel_handle_t)gfx_disp_get_user_data(disp);
    esp_lcd_panel_draw_bitmap(panel, x1, y1, x2, y2, data);
}

void app_main(void)
{
    gfx_core_config_t gfx_cfg = {
        .fps = 30,
        .task = GFX_EMOTE_INIT_CONFIG(),
    };
    gfx_handle = gfx_emote_init(&gfx_cfg);
    if (gfx_handle == NULL) {
        ESP_LOGE(TAG, "Failed to initialize GFX");
        return;
    }

    gfx_disp_config_t disp_cfg = {
        .h_res = 320,
        .v_res = 240,
        .flush_cb = disp_flush_callback,
        .update_cb = NULL,
        .user_data = panel_handle,   // your esp_lcd_panel_handle_t
        .flags = { .swap = true },
        .buffers = { .buf1 = NULL, .buf2 = NULL, .buf_pixels = 320 * 16 },
    };
    gfx_disp = gfx_disp_add(gfx_handle, &disp_cfg);
    if (gfx_disp == NULL) {
        ESP_LOGE(TAG, "Failed to add display");
        gfx_emote_deinit(gfx_handle);
        return;
    }

    gfx_obj_t *label = gfx_label_create(gfx_disp);
    gfx_label_set_text(label, "Hello, ESP Emote GFX!");
    gfx_obj_set_pos(label, 50, 50);
    gfx_label_set_color(label, GFX_COLOR_HEX(0x00FF00));

    gfx_disp_refresh_all(gfx_disp);
    ESP_LOGI(TAG, "GFX application started");
}

Next Steps