refact(vg_lite): abstract common pending release logic

[FASTSHIFT]

Description of the feature or fix

Generalized delayed release logic.

Notes

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[kisvegabor]

I see that you add/remove items to the pending arrays, but can't see where you actually use them, i.e. where you do something with the saved items.

[FASTSHIFT]

I see that you add/remove items to the pending arrays, but can't see where you actually use them, i.e. where you do something with the saved items.

It's here:
https://github.com/lvgl/lvgl/pull/5756/files#diff-a7fd0e4901fa5b7f6cff798f9ae991251b63efe81d4f1a23d6a1911dac4b04a7R175
https://github.com/lvgl/lvgl/pull/5756/files#diff-8bcb9672aff4be3e779cac54c1c52e2bd88dceb6dddc7d7a976c6235db470d12R202

[kisvegabor]

What I can't see is why is it good to add something to the pending list. When/Where do you read the list, and do something with it?

[FASTSHIFT]

What I can't see is why is it good to add something to the pending list. When/Where do you read the list, and do something with it?

Since the cmd buffer of vg-lite only records the address of the image, after submitting the image to the GPU for rendering, we need to prevent the image being rendered from being automatically released by the cache.
Therefore, we need to wait until the GPU is actually rendered before marking the image as releasable. Since rendering is asynchronous, a pending list is needed to record the image information to be released, and the image references are released uniformly in lv_vg_lite_finish.

[kisvegabor]

Clear now, thanks!