Line of garbage pixels on FF1 videos (regression?)

[hrydgard]

From Reddit:

"One pixel or so line of garbage on the opening fmv of FFI. Wasn't there n the previous versions. Tried all drivers and settings, cant get rid of it."

• https://www.reddit.com/r/emulation/comments/lfhu3q/ppsspp_111_is_out/gmpfwtf/?context=3

[Panderner]

But can you send me the screenshot?

[hrydgard]

The reporter didn't include one.

[nassau-tk]

@hrydgard

PPSSPP : v1.11-2
OS：Windows10（64-bit）Japanese
CPU：Ryzen7 3800X（8-core）
GPU：RADEON RADEON RX5700XT
Resolution：2560×1440
RAM：32GB

This GEdump is "Final Fantasy 1 (Japan:ULJM05241)".
Scene of Opening Movie.
If these files help you then I'm happy.
ULJM05241_opening_movie_7files.zip

And, ScreenShot same with dump files.

[unknownbrackets]

Texture is drawn with clamp S and T, but the video texture is 512x512. At 1x, everything is fine because the top 272 pixels are 1:1, drawn in vertical strips. The second draw has what looks like static there - it's just random RAM.

That said, it's set to nearest. So this only happens if you override texture filtering to linear or linear for FMV, and may be influenced by anistropic. It's fine on default texture filtering.

-[Unknown]

[hrydgard]

Alright, cool. One possibility to make it work with linear filtering is, since we're already doing special stuff here for video, we could probably infer dimensions and use shader texture clamp.

[unknownbrackets]

It's actually drawn using throughmode / s16, so in this case we should already know the height and use it to limit hashing. Drawn in vertical strips, though.

It'd likely make sense to generally enable shader tex clamp whenever drawing a 272 tall texture to screen in throughmode. But we'd need to adjust it to handle a clamp that doesn't match the actual size of the bound texture.

-[Unknown]