English Amiga Board


Go Back   English Amiga Board > Coders > Coders. General

 
 
Thread Tools
Old 06 March 2018, 15:21   #1
Steril707
OCS rocks!

 
Join Date: Sep 2016
Location: Amiga Island
Posts: 476
Has anyone tried to get a "Mode 7"-style game working on the Amiga?

Today I saw this and was heavilly impressed:

[ Show youtube player ]

and this

[ Show youtube player ]

And I wondered if this would be possible on an OCS Amiga..
I know the MD has chunky mode, which makes a lot of this 3D stuff faster..

But still...

Add: don't know, why there were two threads created when I clicked "post"... Sorry for that... :/
Steril707 is offline  
Old 06 March 2018, 15:38   #2
fryguy
Registered User
 
Join Date: Aug 2005
Location: Hjo, Sweden
Age: 39
Posts: 765
EDIT: Didn't notice the OCS part.

Both these are AGA only:

[ Show youtube player ]

[ Show youtube player ]

Last edited by fryguy; 06 March 2018 at 16:22.
fryguy is offline  
Old 06 March 2018, 16:04   #3
Galahad/FLT
Going nowhere

Galahad/FLT's Avatar
 
Join Date: Oct 2001
Location: United Kingdom
Age: 45
Posts: 7,026
The first youtube video should be doable in some form. Its highly cheated or at least, the mode 7 engine on that game knows its limitations, which is why it has no very tight turns.

The Sonic one is pretty impressive.

Street Racer was pretty good for the A1200 and the graphics were far more detailed, i'm guessing a cut down version must be at least possible on OCS.
Galahad/FLT is offline  
Old 06 March 2018, 16:12   #4
dlfrsilver
CaptainM68K-SPS France
dlfrsilver's Avatar
 
Join Date: Dec 2004
Location: Melun nearby Paris/France
Age: 41
Posts: 7,824
Send a message via MSN to dlfrsilver
Brian the Lion is the best example of a game using the Mode 7 from the snes
dlfrsilver is offline  
Old 06 March 2018, 16:31   #5
Steril707
OCS rocks!

 
Join Date: Sep 2016
Location: Amiga Island
Posts: 476
I guess I should have specified that I especially meant those perspective floor tiles, not just rotozoom fx..
Steril707 is offline  
Old 06 March 2018, 16:36   #6
Akira
Registered User

Akira's Avatar
 
Join Date: May 2001
Location: New York
Posts: 19,265
There's this too:
[ Show youtube player ]
(in case link doesn't take you to the time, jump to 1h32m55s)
Akira is offline  
Old 06 March 2018, 16:51   #7
DamienD
Global Moderator

DamienD's Avatar
 
Join Date: Aug 2005
Location: Australian in London
Age: 42
Posts: 12,601
Quote:
Originally Posted by Steril707 View Post
Add: don't know, why there were two threads created when I clicked "post"... Sorry for that... :/
Other duplicate thread now removed
DamienD is offline  
Old 06 March 2018, 16:54   #8
Steril707
OCS rocks!

 
Join Date: Sep 2016
Location: Amiga Island
Posts: 476
Quote:
Originally Posted by DamienD View Post
Other duplicate thread now removed
Thanks, Damien...
Steril707 is offline  
Old 06 March 2018, 22:55   #9
chb
Registered User

 
Join Date: Dec 2014
Location: germany
Posts: 103
Just a note: Both the "Sonic Kart" and the F-Zero clone are by gasega68k/Stephane Dallongeville, which was also active here at eab as "Stef_" (account closed unfortunately).

The Mr. Nutz fly stage is not Mode7-like, as it's only zooming without rotation. Uses the scroll register trick to scale the lines.

But concerning the original question: I do not know of any examples, maybe there are some demo parts?
chb is online now  
Old 07 March 2018, 00:16   #10
saimon69
J.M.D - Bedroom Musician

 
Join Date: Apr 2014
Location: los angeles,ca
Posts: 858
I remember some copper chunky perspective demos in the past but those were having the zoom and not rotation; plus i seems to remember the limit of 8 pixels for the OCS/ECS copper; road might look pretty blocky but if we focus on playability that should be fine
saimon69 is offline  
Old 07 March 2018, 00:51   #11
malko
Registered User

malko's Avatar
 
Join Date: Oct 2017
Location: CH
Posts: 844
Quote:
Originally Posted by chb View Post
Just a note: Both the "Sonic Kart" and the F-Zero clone are by gasega68k/Stephane Dallongeville, which was also active here at eab as "Stef_" (account closed unfortunately).[...]
Maybe one Moderator could look at the closed profile and try to send him an e-mail ??
malko is offline  
Old 07 March 2018, 10:29   #12
Steril707
OCS rocks!

 
Join Date: Sep 2016
Location: Amiga Island
Posts: 476
Would be amazing, if he could join in the discussion and explain a bit how he accomplished the outstanding work he did on the MD..
Steril707 is offline  
Old 07 March 2018, 11:41   #13
alexh
Thalion Webshrine
alexh's Avatar
 
Join Date: Jan 2004
Location: Oxford
Posts: 12,146
Quote:
Originally Posted by Galahad/FLT View Post
Street Racer was pretty good for the A1200 and the graphics were far more detailed, i'm guessing a cut down version must be at least possible on OCS.
Would that be considered a "Mode 7" game? The playfield is very narrow. You can never see any other parts of the track other than the bits you're driving on. It's more like OutRun than Mario Kart / F-Zero.
alexh is offline  
Old 07 March 2018, 17:18   #14
Akira
Registered User

Akira's Avatar
 
Join Date: May 2001
Location: New York
Posts: 19,265
Quote:
Originally Posted by alexh View Post
It's more like OutRun than Mario Kart / F-Zero.
Yeah agreed, not mode7-type effects, it was mode7-like on the SNES, but not on the MD/Amiga

SNES/Sega:
[ Show youtube player ]

Sega/Amiga:
[ Show youtube player ]
(look at that, the AMiga version seems smoother)
Akira is offline  
Old 07 March 2018, 18:27   #15
DanScott
Lemon. / Core Design

DanScott's Avatar
 
Join Date: Mar 2016
Location: Belgrade, Serbia
Posts: 319
You *could* do something like this on OCS Amiga

You could go for a copper screen 8x8,8x4,8x2 pixels.. or even a "fake" 4x4 (or 4x2) as used in some demos (see Unique - Multicolor demo for example)

[ Show youtube player ]


Another alternative is to use a HAM 4x4 (or 4x3, 4x2) using the 7 bitplane trick (that enabled HAM mode but only enables 4 DMA channels.. the Modify bitplanes are written directly to the Bitplane 5 & 6 data registers)

This was used in the following demo:

[ Show youtube player ]


With a game engine like this, you would not be able to use just a bitmap for a track or floor, as the resolution would be too small for anything expansive. Your rendering code (for each "pixel") would need to index a block, then to index a pixel in that block, so the overhead is somewhat more. You could precalculate quite a lot of lookup tables for this, but then memory usage would also be quite high

But the answer is yes, I think that this could be done on a500
DanScott is offline  
Old 07 March 2018, 18:36   #16
Akira
Registered User

Akira's Avatar
 
Join Date: May 2001
Location: New York
Posts: 19,265
Those examples are rotozoomers, don't look at all to what Steril wants to do, really. He alredy mentioned "no rotozoomeers" on an above post.
Akira is offline  
Old 07 March 2018, 18:54   #17
malko
Registered User

malko's Avatar
 
Join Date: Oct 2017
Location: CH
Posts: 844
Quote:
Originally Posted by malko View Post
Maybe one Moderator could look at the closed profile and try to send him an e-mail ??
By PM I have asked DamienD. Unfortunately he answered me that there is no e-mail available.
Sorry Steril707. Maybe an EAB member knows somebody who knows somebody that can contact him (I know it's like trying to send an e-mail to a 20 years old address, but who knows... )
malko is offline  
Old 07 March 2018, 21:52   #18
DanScott
Lemon. / Core Design

DanScott's Avatar
 
Join Date: Mar 2016
Location: Belgrade, Serbia
Posts: 319
Quote:
Originally Posted by Akira View Post
Those examples are rotozoomers, don't look at all to what Steril wants to do, really. He alredy mentioned "no rotozoomeers" on an above post.
1) As the A500 can't push pixels to the screen partcularly quickly, I was giving examples of screen modes that *could* be used to display a mode 7 style floor

2) If you ever investigated how a mode 7 style floor works, it is essentially the same as a rotozoomer, except that the x/y texel positions and dx/dy are calculated slightly differently. Other than that, the inner workings of the 2 should be practically identical.
DanScott is offline  
Old 07 March 2018, 23:29   #19
chb
Registered User

 
Join Date: Dec 2014
Location: germany
Posts: 103
Stephane is still active on the Sega16 forum, so should be easy to contact him there:

http://www.sega-16.com/forum/member....1357-gasega68k

I'd guess blitter-assisted c2p should be fast enough to do a 2x2 (or fake 1x2 like in britelite's wolf3d demo and seemingly gasega6k's demos) mode7 at half screen height at a reasonable frame rate, maybe using some self-modifying code for the texture mapper. But I do not see an obvious approach for the scaling in z - you'd need to generate code for every line because the scaling is different, in a rotzoomer it's fixed and you need only to generate code for a single line. Maybe a combination of c2p and scroll register trickery?
chb is online now  
Old 08 March 2018, 10:00   #20
Steril707
OCS rocks!

 
Join Date: Sep 2016
Location: Amiga Island
Posts: 476
@Dan Scott:
Super interesting idea, using Copper Chunky.
I guess first off, you'd need to calculate tiles into an intermediate buffer, and after that move everything into one of two copperlists.
Steril707 is offline  
 


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
What are "VGA mode resolution autoswitch" and "Variable sync"? Foebane support.WinUAE 2 09 November 2017 22:21
Keep Active control panel "Line Mode" and "Interlaced Line Mode" Zilog request.UAE Wishlist 4 03 August 2014 00:08
Looking for a "Gauntlet" style game SilverHand Looking for a game name ? 7 21 January 2005 20:05
Looking for a "Wild West" - style, game name... Shoonay Looking for a game name ? 3 22 October 2004 00:25

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +2. The time now is 16:35.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2018, vBulletin Solutions Inc.
Page generated in 0.11286 seconds with 13 queries