Screen Flip on Mode 3

Topics related to the API, programming discussions & questions, coding tips, bugs, etc. should go here.
Post Reply
User avatar
ggvicviper
Posts: 16
Joined: Sat Oct 24, 2015 8:54 pm

Screen Flip on Mode 3

Post by ggvicviper »

Hi, I was wondering if there was a way to flip the screen in Mode 3. I'm building another game for the JAMMA UzeBox, but I'd like to be able to render things 180 degrees if need be. Is there an easy way to do this, or even a way to potentially edit the Kernel to do so?
User avatar
uze6666
Site Admin
Posts: 4778
Joined: Tue Aug 12, 2008 9:13 pm
Location: Montreal, Canada
Contact:

Re: Screen Flip on Mode 3

Post by uze6666 »

So you need horizontal flipping or really 180 degrees rotation? And permanent or dynamically settable? In any of those cases there's no quick way to do this. You need to create a new video mode derived from mode3. It's pretty doable.
User avatar
ggvicviper
Posts: 16
Joined: Sat Oct 24, 2015 8:54 pm

Re: Screen Flip on Mode 3

Post by ggvicviper »

Well, it would be both horizontal and vertical flipping, so yeah, 180 degrees. It would need to be dynamic, too.
User avatar
uze6666
Site Admin
Posts: 4778
Joined: Tue Aug 12, 2008 9:13 pm
Location: Montreal, Canada
Contact:

Re: Screen Flip on Mode 3

Post by uze6666 »

It's indeed quite possible to have such a mode but the simplest solution would require a second render loop since you have to traverse the RAM and tiles data "backwards". What would be the purpose of such screen rotation?
User avatar
ggvicviper
Posts: 16
Joined: Sat Oct 24, 2015 8:54 pm

Re: Screen Flip on Mode 3

Post by ggvicviper »

Most vertical arcade games have an option for this via dipswitch, since machines can vary which way they rotate the screen to be vertical. Was wondering if there was any way to do this easily with Mode 3.
Post Reply