Forums

Hello,

While developping my SMS emulator, I found glitches at the extreme columns of the screen of the game outrun. I couldn't really understand the problem, that seems to be related to the scrolling.

Trying others emulator (Meka for example, Cf screenshot), this glitch is also existing.

I assume this is a known "issue"...is there any additional information about it ? Is it an emulation issue ?

Thanks !

outrun.jpg (90.08 KB)

All games like this work by drawing a mostly static road and applying different horizontal scroll values to each line. For a wide road or when moving off the road like this, it means the road would disappear off one side and appear on the other. The game tries to minimise this by making the road into sand as much as possible, but some corners poke across the edges. If you disable the scrolling effect, or look at the tile map viewer in Meka, you can see what is going on. You will see the same on a real system, but older CRTs cut off the screen edges and hide it a bit.

Thanks for the information.
I played this game on SMS few years ago (30?!)...I do not remind this detail. This may be because I used to stay on the road ;)

I mostly played this game on the Game Gear, but the version is very different.

The Master System and Game Gear both have a virtual screen resolution of 256x224, meaning that the Game Gear has plenty of off-screen space to hide the road whereas the Master System only has 8 pixels horizontally. Thus it’s easier for Game Gear games to avid this issue.

Author	Message
cgyed.cgyed Joined: 10 Feb 2020 Posts: 6	Outrun glitch Posted: Sun Nov 08, 2020 6:35 pm
cgyed.cgyed Joined: 10 Feb 2020 Posts: 6	Hello, While developping my SMS emulator, I found glitches at the extreme columns of the screen of the game outrun. I couldn't really understand the problem, that seems to be related to the scrolling. Trying others emulator (Meka for example, Cf screenshot), this glitch is also existing. I assume this is a known "issue"...is there any additional information about it ? Is it an emulation issue ? Thanks ! outrun.jpg (90.08 KB)

Maxim Site Admin Joined: 19 Oct 1999 Posts: 14745 Location: London	Posted: Sun Nov 08, 2020 6:47 pm
	All games like this work by drawing a mostly static road and applying different horizontal scroll values to each line. For a wide road or when moving off the road like this, it means the road would disappear off one side and appear on the other. The game tries to minimise this by making the road into sand as much as possible, but some corners poke across the edges. If you disable the scrolling effect, or look at the tile map viewer in Meka, you can see what is going on. You will see the same on a real system, but older CRTs cut off the screen edges and hide it a bit.

cgyed.cgyed Joined: 10 Feb 2020 Posts: 6	Posted: Sun Nov 08, 2020 7:46 pm
cgyed.cgyed Joined: 10 Feb 2020 Posts: 6	Thanks for the information. I played this game on SMS few years ago (30?!)...I do not remind this detail. This may be because I used to stay on the road ;) I mostly played this game on the Game Gear, but the version is very different.

Maxim Site Admin Joined: 19 Oct 1999 Posts: 14745 Location: London	Posted: Sun Nov 08, 2020 8:07 pm
	The Master System and Game Gear both have a virtual screen resolution of 256x224, meaning that the Game Gear has plenty of off-screen space to hide the road whereas the Master System only has 8 pixels horizontally. Thus it’s easier for Game Gear games to avid this issue.

Forums

View topic - Outrun glitch