sorgelig
commented
2 years ago I don't think it can be improved. It's a feature not present in original HW. Original HW is relaying on poor TV quality where some blending may give pseudo-transparency. Option is relaying just on one aspect which is easy to detect. Other possible option is to add composite blend which will worsen whole video on screen which i'm sure not a good option.
No-Intro: Nintendo - Super Nintendo Entertainment System — Tokimeki Memorial - Densetsu no Ki no Shita de (Japan) (Rev 1).sfc CRC32: AE9F3602 MD5: cd36eb8982de4bf8369deb9f2f23e590 English translated rom CRC32: C3442E00
Tokimeki Memorial: Densetsu no Ki no Shita de, a game which recently got an English patch, displays an issue with pseudo transparency option. The UI, rendered partly in high resolution to fit large portions of text, features a shadow which drops to lower parts of the interface, but with Pseudo Transparency option set to Blend, required to get transparency in some games, the whole shadow disappears. This issue is present in both the original Japanese version and the patched English version. Setting the Pseudo Transparency to Off aliviates the issue.
Pseudo Transparency: Off
Pseudo Transparency: Blend
(Native resolution screenshots stretched vertically to 448 pixels to preserve the aspect ratio).
As you can see the portions of the screen above and below the image box turn slightly softer and shift a bit to the right, but the shadow effect disappears completely. Interestingly, the shadow is present when enabling Force 256px option, making me believe that this is a true transparency effect and it should not be blended altogether.
Force 256px: On, Pseudo Transparency: Off
While turning off Pseudo Transparency fixes the issue in this particular game, it requires the user to know there's an issue in the first place and understand how to solve it with core options. So I believe that the pseudo transparency support could be probably improved to not rely on end user understanding SNES's video rendering quirks.