Lv_img_set_angle() causes distortion or flip when rotating .bin image in LVGL v8

[e2718281689]

Description

When using LVGL v8 to load images converted with the LVGL Image Converter (in .bin format), the image displays correctly by default, but becomes distorted or appears “flipped”/“mirrored” when rotated using lv_img_set_angle().

What MCU/Processor/Board and compiler are you using?

esp32c3

What do you want to achieve?

• LVGL version: v8
• Image format: generated using LVGL’s official Image Converter, output as .bin
• Color format: LV_IMG_CF_TRUE_COLOR (or TRUE_COLOR_ALPHA)
• Image renders correctly before rotation
• After rotation, the image appears as a thin line or looks like it’s been “flipped” or “mirrored”
• bin file format images can be rotated correctly

What have you tried so far?

The generated C code image can be rotated normally, but the bin image cannot

Code to reproduce

    // 获取当前屏幕
    lv_obj_t *scr = lv_disp_get_scr_act(disp);

    // 创建图像对象
    lv_obj_t *img = lv_img_create(scr);
    lv_img_set_src(img, "A:/littlefs/moiw_2014.bin"); // 使用LittleFS中的图像文件
    // lv_img_set_src(img, &moiw_2014); // 使用LittleFS中的图像文件

    // 设置图像中心对齐
    lv_obj_center(img);

    // 允许旋转和缩放（开启变换属性）
    lv_img_set_pivot(img, 100 ,100); // 设定旋转中心
    lv_img_set_angle(img, 0); // 初始角度：0°

    // 创建动画旋转图像
    lv_anim_t a;
    lv_anim_init(&a);
    lv_anim_set_var(&a, img);
    lv_anim_set_values(&a, 0, 3600); // 单位是0.1°，3600 = 360°
    lv_anim_set_time(&a, 3000); // 3秒一圈
    lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
    lv_anim_set_exec_cb(&a, (lv_anim_exec_xcb_t)lv_img_set_angle);
    lv_anim_start(&a);

Screenshot and/or video

If possible, add screenshots and/or videos about the current state.

image