How to change the transparency of one part of picture ,and the other part remain the same

How-to
1

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Description

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

IMXRT1052

What LVGL version are you using?

V8

What do you want to achieve?

Change the transparency of one part of picture ,and the other part remain the same.

What have you tried so far?

Code to reproduce

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Screenshot and/or video

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2

You can’t simply edit an image this way.

There would be possible to create a custom mask but it’s quite complicated and I don’t recommend going so deep.

What is the use case? Maybe there is an other, simpler solution.

3

Similar to the example of the progress bar, the progress bar uses a picture, the current progress point uses a line, the left side of the line changes transparency, and the right side remains unchanged

4

For this you can simply set the width of the image and it’d be clipped.

5

Thanks,
Use this way , i can show the left part of the image , but can’t show the right part of the image .

6

Using lv_img_set_offset_x(img, x); too should help.