Improper rendering at higher resolutions

[smiga0303]

First of all I want to apologize, I know this question must've been asked before but I don't know what to search for or what's it called.
Assassin's Creed: Bloodlines has... artifacts? that become increasingly pronounced as I up the rendering resolution.

1x: https://i.imgur.com/tCaprgp.png
4x: https://i.imgur.com/6QqT3yk.png
10x: https://i.imgur.com/n52XcRO.png

Can anything be done about this? I know non-native rendering always introduces problems. I've tried different combinations of texture scaling and filtering, but to no avail.
Thank you

[[Unknown]]

Two things here.

One is already explained in: https://forums.ppsspp.org/showthread.php?tid=13556

The other, sometimes PSP games render effects to cause blur. For example:
* They render the entire scene.
* Then they take a screenshot of that scene, and render it to a temporary buffer that's 1/4 the size.
* Then they render that screenshot again, but offset by one in each of the four directions.
* Then they do that all again, 1/4 of the size once more (so now, 1/16 the size.)
* Then even one more time, 1/4 again to 1/64 the size.
* Then they use that to render some "blur effects" on the screen.

At the PSP's 1x resolution of 480x272, 1/64 is 30x17, which means things are pretty blurry when it scales it back up to the screen. But at 10x resolution, that's 300x170, which still has plenty of detail. Thus, the effect still looks kinda sharp and you get weird ghosting.

There's an option to try to avoid this, which basically just forces temporary graphics buffers used by the game to render at a lower resolution.

That probably isn't causing the line gaps at 4x, but might be causing the pattern at 10x (especially because it probably draws these effects in vertical strips of about that size.)

-[Unknown]