Metroid 2: Minor Graphical glitches

[georgehb]

Glitch 1

When this enemy is just off screen, incorrect sprites are shown

Easily seen when standing on the lower ledge, sprite flickers rapidly between the two shown screen shots

In mGBA the enemy is not visible at all from lower ledge

Glitch 2

When loading from a save, the save room loads incorrectly

These glitches are more than just graphical and can even be stood on

And Samus can fit in the blank space in the collumn whilst a ball

Once you move the incriminating tiles off screen they then loads normally. This error has only been found to occur when first starting up the game

Unbroken room for comparison

[georgehb]

Here is a nearby save for Glitch 1. Head right until you reach a tall vertical room it's the first enemy at the top of this room

(I had to save as an image so just rename the file)

[philj56]

Note to self: this is definitely in gbcc_ppu.c

[philj56]

The first glitch should be solved in c32eaab28f2ff4c83f2a7f1a2b3576e7eca77f23. It was being caused by a negative overflow in the ppu when an 8x8 sprite was within the top 8 pixels of the screen.

[philj56]

At long last this can be closed I think - the saves got fixed somewhere in 0d4fa8b52d6f79e10319135f9c7d676a213607a7. No more magical glitch world exploration.