Does the AGA chipset has been fully exploited ?

[DamienD]

Originally Posted by mcgeezer

Purely for technical purposes, does anyone have a working download link for Flink for the CD32.

I want to check what screen mode / fetch mode the game is running in and what it does with the sprites.

Alternatively, if someone know a good webpage with the information I would be most grateful.

Geezer

G, it's in my collection that you have

[mcgeezer]

Originally Posted by DamienD

G, it's in my collection that you have

First place i looked and its not there for some bizarre reason.

I’ll have another look when i get home.

[skan]

Originally Posted by Steril707

Or to give another example, I understand why there are only three dual playfield levels in Lionheart.

Off course those levels look amazing when you first see them, but if every level had only those shades of brown and grey in the foreground it would start to look boring after a few levels.
Plus, on Agony where they do this, you could barely make out the enemies in front of the same coloured background.

...But those are OCS games.

[aros-sg]

Originally Posted by mcgeezer

Flink for the CD32.

I was curious too some time ago and in first level at least it seems normal 64 color screen and hw sprites for parallax layer. And only 25 FPS.


64 color because Genesis/Mega Drive has 4x16 color palettes so with normal dual playfield speed may have been better (50 FPS) but not enough colors to match nice gfx of game on Sega's hardware.

[mcgeezer]

Originally Posted by aros-sg

I was curious too some time ago and in first level at least it seems normal 64 color screen and hw sprites for parallax layer. And only 25 FPS.


64 color because Genesis/Mega Drive has 4x16 color palettes so with normal dual playfield speed may have been better (50 FPS) but not enough colors to match nice gfx of game on Sega's hardware.

Can u remember how wide the playfield is?

[DamienD]

Originally Posted by mcgeezer

First place i looked and its not there for some bizarre reason.

I’ll have another look when i get home.

It was included ages ago, in Update Pack #23

[ross]

Originally Posted by mcgeezer

Can u remember how wide the playfield is?

px=288, py=176

FMODE = x2 bitplanes, x4 sprites, DDFSTRT = $30, 6 BPLs
11 DMA fetches for BPLs = 352 - (2x32) for x-scroll, DIWx = $91 to $1b1, DIWy = $38 to $E8

no SSCAN2 trick for sprites, 'normal' x copper multiplex

[mcgeezer]

Originally Posted by DamienD

It was included ages ago, in Update Pack #23

Spot on, will take a look shortly.

Originally Posted by ross

px=288, py=176

FMODE = x2 bitplanes, x4 sprites, DDFSTRT = $30, 6 BPLs
11 DMA fetches for BPLs = 352 - (2x32) for x-scroll, DIWx = $91 to $1b1, DIWy = $38 to $E8

no SSCAN2 trick for sprites, 'normal' x copper multiplex

I’ll have to take another look, the sprites must be only 4 colours then for background.

Edit- they actually look like 2x16 colour sprites, 128px wide repeated - risky woods style.

[ross]

Originally Posted by mcgeezer

I’ll have to take another look, the sprites must be only 4 colours then for background.

No, only 4 are used for the background at 64x2x16colours.

With a 3x multiplexing you can cover 128*3=384 that is more than enough for a full scrolling 288 px screen.



EDIT: missed your edit

[mcgeezer]

Originally Posted by ross

No, only 4 are used for the background at 64x2x16colours.

With a 3x multiplexing you can cover 128*3=384 that is more than enough for a full scrolling 288 px screen.

Thanks Ross.

Off topic and i might start another thread, also not at a kryboard.

I’m thinking of the best screen mode for a game like impossible mission, but possibly hi-res with x-axis scrolling. My thoughts are around somehow using the sprites to expand the size of the dual playfield so that the 32 pixels either side are not lost on scrolling.

[ross]

Originally Posted by mcgeezer

I’m thinking of the best screen mode for a game like impossible mission, but possibly hi-res with x-axis scrolling. My thoughts are around somehow using the sprites to expand the size of the dual playfield so that the 32 pixels either side are not lost on scrolling.

[OFFTOPIC, but not much]
No need for it in hi-res: if you go for FMODE=BPLs x2 and use DDFSTRT=$30 then the shifter draw the first pixel at $71 and if you scroll you can use $81 as DIWx start value (old DIW registers are in low-res pixel metric so a gap of 16 is 32 hi-res pixels).
Problem here is that for a dual playfield 4+4bpls in hi-res you fill in DMA fetches..
[/OFFTOPIC]

[mcgeezer]

Originally Posted by ross

[OFFTOPIC, but not much]
No need for it in hi-res: if you go for FMODE=BPLs x2 and use DDFSTRT=$30 then the shifter draw the first pixel at $71 and if you scroll you can use $81 as DIWx start value (old DIW registers are in low-res pixel metric so a gap of 16 is 32 hi-res pixels).
Problem here is that for a dual playfield 4+4bpls in hi-res you fill in DMA fetches..
[/OFFTOPIC]

I think i’ll do some experimentation with this.
I was recently reading some of the overscan techniques used on the Atari ST and so i’m going to see if i can get full overscan in hi-res with dual playfield.(or 32x8 split). The hardware sprites are expendable.

[Steril707]

Originally Posted by skan

...But those are OCS games.

I know, but I was answering to this statement of yours...

Originally Posted by skan

Is there such thing as a "generic engine" on Amiga really...or need of one?!?

[skan]

Originally Posted by Steril707

I know, but I was answering to this statement of yours...

Ok.

[roondar]

Originally Posted by Steril707

I'd love to see a 64 color game, for instance.

Originally Posted by skan

Completely agree on the 64 color game!

Just for reference, both Aladdin and The Lion King run in 64 colour mode and seem to use the Blitter to create the background layer.

[Gilbert]

Originally Posted by DamienD

Flink starts with a NTSC screenmode:

You press the Green button to switch to PAL:

I didn't know that - that's a lot better but it's still bordered on the width, which is a shame. If you comapre to the Mega CD I think the Mega CD has a bigger view window (can't remember exactly now) but I'm sure the Amiga could have done this too

[aros-sg]

Originally Posted by aros-sg

And only 25 FPS.

Btw, I think there may be a chance to hack games like this to run in 50 FPS for emulators (where blitter has no speed limit) because I find it unlikely that the game logic was modified to run on 25 FPS. Instead it likely is just called twice per 25 Hz or even same as on Sega HW = 1 per 50 Hz and it's just the display that is split over two frames.

[Steril707]

Originally Posted by Gilbert

I didn't know that - that's a lot better but it's still bordered on the width, which is a shame. If you comapre to the Mega CD I think the Mega CD has a bigger view window (can't remember exactly now) but I'm sure the Amiga could have done this too

Going overscan takes away some other stuff as far as I know.

[kremiso]

Originally Posted by mcgeezer

...I’m thinking of the best screen mode for a game like impossible mission...

oh man, i would like to see a new approach also for that one
...at least to reach to remove that bad '2025' echoes sound in my ears

[Foebane]

Originally Posted by aros-sg

Btw, I think there may be a chance to hack games like this to run in 50 FPS for emulators (where blitter has no speed limit) because I find it unlikely that the game logic was modified to run on 25 FPS. Instead it likely is just called twice per 25 Hz or even same as on Sega HW = 1 per 50 Hz and it's just the display that is split over two frames.

The point of emulation is that it emulates the real hardware, so bending the rules as you suggest means that such a "hacked" game would not run on a real A500 or whatever. If we start heading in this direction we may as well separate WinUAE from a real Amiga and call it its own incompatible thing.