LVGL控件边缘出现莫名亮点

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LVGL控件边缘出现莫名亮点，并且这样的问题会随着设置LVGL初始化时候的缓冲buff大小而改变点点的数量，当把缓冲减小的时候点点就会明显变多，buff越大，点点越小，我使用的是ESP32S3芯片，采用LVGL8.3模板，以下是buff设置大小不同的情况

[15172072715]

无论是在guider上面还是用模拟器都不存在点点的情况

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[asd3330303]

/中文 start**********/
参考(https://www.esp32.com/viewtopic.php?f=25&t=28324&p=118360#p118360)，已解决问题哈哈，这个问题卡了我半年
在函数void ili9488_flush(lv_disp_drv_t * drv, const lv_area_t * area, lv_color_t * color_map)
里最后
ili9488_send_color((void ) mybuf, size * 3);
ili9488_send_color((void ) (&mybuf[(size * 3) - 3]), 3);//增加的，本质是将最后一个像素再发一次
heap_caps_free(mybuf);
/中文 END********/

/English start**********/
thanks for(https://www.esp32.com/viewtopic.php?f=25&t=28324&p=118360#p118360)
The problem has been solved. The problem has stuck me for half a year
In function: void ili9488_flush(lv_disp_drv_t * drv, const lv_area_t * area, lv_color_t * color_map)
ili9488_send_color((void *) mybuf, size * 3);
ili9488_send_color((void *) (&mybuf[(size * 3) - 3]), 3);//need add. Essentially, you send the last pixel again
heap_caps_free(mybuf);

/English END**********/

[asd3330303]

/中文 start**********/
根因已找到了，是因为数据加入发送队列的之后，我们就free掉buffer了，所以存在野数据问题，野数据是导致亮点的原因。在发送和free之间加入disp_wait_for_pending_transactions();也可以解决这问题（弊端是会降低刷新率)
最下面的代码是完美解决方案
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/English start**********/
The root cause has been found, because after the data is added to the send queue, we will free the buffer, so there is a wild data problem, wild data is the cause of the bright spot. Add disp_wait_for_pending_transactions() between send and free; It can also solve this problem (the disadvantage is that it will reduce the refresh rate)

The bottom code is the perfect solution

/English END**********/

void ili9488_flush(lv_disp_drv_t * drv, const lv_area_t * area, lv_color_t * color_map)
{
    uint32_t size = lv_area_get_width(area) * lv_area_get_height(area);

    lv_color16_t *buffer_16bit = (lv_color16_t *) color_map;
    static uint8_t *mybuf = NULL;

    if (mybuf != NULL){
        disp_wait_for_pending_transactions();//等待发完后重新申请地址
        heap_caps_free(mybuf);
        mybuf = NULL;
    }

    do {
        mybuf = (uint8_t *) heap_caps_malloc(3 * size * sizeof(uint8_t), MALLOC_CAP_DMA);
        if (mybuf == NULL)  ESP_LOGW(TAG, "Could not allocate enough DMA memory!");
    } while (mybuf == NULL);

    uint32_t LD = 0;
    uint32_t j = 0;

    for (uint32_t i = 0; i < size; i++) {
        LD = buffer_16bit[i].full;
        mybuf[j] = (uint8_t) (((LD & 0xF800) >> 8) | ((LD & 0x8000) >> 13));
        j++;
        mybuf[j] = (uint8_t) ((LD & 0x07E0) >> 3);
        j++;
        mybuf[j] = (uint8_t) (((LD & 0x001F) << 3) | ((LD & 0x0010) >> 2));
        j++;
    }

	/* Column addresses  */
	uint8_t xb[] = {
	    (uint8_t) (area->x1 >> 8) & 0xFF,
	    (uint8_t) (area->x1) & 0xFF,
	    (uint8_t) (area->x2 >> 8) & 0xFF,
	    (uint8_t) (area->x2) & 0xFF,
	};
	
	/* Page addresses  */
	uint8_t yb[] = {
	    (uint8_t) (area->y1 >> 8) & 0xFF,
	    (uint8_t) (area->y1) & 0xFF,
	    (uint8_t) (area->y2 >> 8) & 0xFF,
	    (uint8_t) (area->y2) & 0xFF,
	};

	/*Column addresses*/
	ili9488_send_cmd(ILI9488_CMD_COLUMN_ADDRESS_SET);
	ili9488_send_data(xb, 4);

	/*Page addresses*/
	ili9488_send_cmd(ILI9488_CMD_PAGE_ADDRESS_SET);
	ili9488_send_data(yb, 4);

	/*Memory write*/
	ili9488_send_cmd(ILI9488_CMD_MEMORY_WRITE);

	ili9488_send_color((void *) mybuf, size * 3);
    
	// heap_caps_free(mybuf);
}