Odd Glitch in "Sonic Mega Collection"

10-09-2016, 10:33 AM #1

So I was playing "Sonic Mega Collection" and obviously seeing as it was a ton of Genesis games, it mainly ran well. Except for Sonic 3. (And Sonic 3 & Knuckles) The main parts of the game played fine, however the file select and the special stages have this annoying flickering affect, which made it near impossible to play. Anyone know a fix for this?

Craftyawesome · 10-09-2016, 11:53 AM #2

https://wiki.dolphin-emu.org/index.php?title=Sonic_Mega_Collection
"Problems
Frame Issues
When the game lags, it is possible that it will duplicate or show the wrong frames in the wrong order. This is most evident in Blue Sphere; where it will happen when there are any number of spheres on the screen. In order to avoid this, enable "Emulated CPU Clock Override" and set it to 150% or higher."

drhycodan · 10-10-2016, 01:55 AM #3

How come the GC is capable of running the special stages at full speed while dolphin requires the emulated cpu to be overclocked?

**JosJuice** · 10-10-2016, 02:01 AM #4

(10-10-2016, 01:55 AM)drhycodan Wrote: How come the GC is capable of running the special stages at full speed while dolphin requires the emulated cpu to be overclocked?

Dolphin is not perfect at knowing what speed the original hardware would run something at. Usually, Dolphin with the CPU clock set to 100% runs faster than a real console, but some emulated software and video decoding can actually run slower than a real console. (By emulated software, I mean when the real console emulates another console, meaning Dolphin has to emulate a GC/Wii that emulates another console.)

drhycodan · 10-10-2016, 02:15 AM #5

Sonic 3 and knuckles runs the special stages full speed with genesis plus emulator.

10-10-2016, 03:40 AM #6

(10-09-2016, 11:53 AM)Craftyawesome Wrote: https://wiki.dolphin-emu.org/index.php?title=Sonic_Mega_Collection
"Problems
Frame Issues
When the game lags, it is possible that it will duplicate or show the wrong frames in the wrong order. This is most evident in Blue Sphere; where it will happen when there are any number of spheres on the screen. In order to avoid this, enable "Emulated CPU Clock Override" and set it to 150% or higher."

Thanks, tried this and it ran perfectly.

**mbc07** · 10-10-2016, 05:59 AM #7

(10-10-2016, 02:15 AM)drhycodan Wrote: Sonic 3 and knuckles runs the special stages full speed with genesis plus emulator.

Genesis Plus is emulating Sonic 3 & Knuckles directly. Dolphin is emulating a GameCube which is emulating whatever emulator the Sonic Mega Collection dev team chose. In other words, you're emulating an emulator.

drhycodan · 10-11-2016, 01:05 AM #8

Sorry, I forgot to add the fact that I was running Genesis Plus ON Dolphin, not a real GC. Same scenario, emulating on an emulator.

**mbc07** · 10-11-2016, 04:31 AM #9

Different implementations. The emulator chosen by Sonic Mega Collection devs probably relies on something not emulated correctly by Dolphin while Genesis Plus doesn't, which explains the glitch...