How does X2:Megablast parallax with all that colors?

[AmigaHope]

Given that it's just 16 colors, why not an AGA dual-playfield modification? Then the background layer routine could be replaced with a scroll routine, freeing up performance. If the background is drawn in a separate pass, you could even just replace that bit of code in the existing code and leave the rest unmolested, then find the frameskip routine and set it to 25fps (I assume game logic would break and everything would run too fast then, but this would initially just be for proof of concept).

A first test would be to find the routine that draws the background layer and just NOP the call to it (or BRA/JMP ahead if it's inlined). If it's that easy a change, then the background draw/scroll routine can be replaced wholesale without changing the rest of the code of the game.

[sandruzzo]

For my Proxima 3 Aga,I've used a very simple solution since all THAT ram: second and third layers were built into chip and in order to scroll them, I've just change bitplane pointers. For Foreground same shit, it was build into fast-ram, and with cpu, I just copy strips...

[mcgeezer]

Doing it on aga would be easy, 50 frames no problem.
Ocs is a different story.

[DanScott]

Originally Posted by AmigaHope

A first test would be to find the routine that draws the background layer and just NOP the call to it (or BRA/JMP ahead if it's inlined). If it's that easy a change, then the background draw/scroll routine can be replaced wholesale without changing the rest of the code of the game.

I would imagine that the background layer and foreground layer are drawn in 1 pass, combining the data (masking foreground against background) and then written to the screen buffer

[Tigerskunk]

Originally Posted by AmigaHope

Given that it's just 16 colors, why not an AGA dual-playfield modification?.

If we go AGA/A1200 anyway, we would not even have this discussion.

Would be easy to get this going at 50 fps and the game looking like it does.

add/edit: I see McGeezer already covered this..

[sandruzzo]

Originally Posted by mcgeezer

Doing it on aga would be easy, 50 frames no problem.
Ocs is a different story.

In fact it was!

[Hewitson]

Originally Posted by mcgeezer

Try this poke in WinUAE to turn it from the pile of shit it is into a super top notch shooter:

Sorry, but it's still a pile of shit

[mcgeezer]

Originally Posted by Hewitson

Sorry, but it's still a pile of shit

I was being sarcastic.

[skan]

Originally Posted by Hewitson

Sorry, but it's still a pile of shit

Sorry, but you're wrong!

[mcgeezer]

Originally Posted by DanScott

I would imagine that the background layer and foreground layer are drawn in 1 pass, combining the data (masking foreground against background) and then written to the screen buffer

From what I can gather by watching the blitter registers they do the following:

Copy the background layer over writing planes 1 and 2.
Copy Blit all the foreground tiles that are on the near edges
Copy Blit all the foreground tiles that are on the outer edges on planes 3 & 4
Cookie Blit the foreground tiles that are on the outer edges on planes 1 & 2
Cookie Blit the sprites

I havent quite worked out what it's doing for the screen rebuild on the sprites, it's doing something weird.

Certainly interesting to look at this.

[Hewitson]

Originally Posted by skan

Sorry, but you're wrong!

No. You're wrong. Play a few Japanese shoot em ups from the same era. Thunder Force IV, for example.

[Tigerskunk]

Originally Posted by Hewitson

No. You're wrong. Play a few Japanese shoot em ups from the same era. Thunder Force IV, for example.

I think it's a bit unfair to have Xenon2 (a very early 16 bit game) pitted against a game that was created 4 years later.

I think at that time the Europeans were just trying to find their footing with SHMUPs.

R-type was just released in japanese arcades a year earlier, and the ideas of what a good SHMUP should have in it were not around at that time.

(and yeah, X2 is shit... )

[roondar]

Please understand, I really hate Xenon 2. I find it unplayable and one of the most overrated games of the 16 bit era. So, I agree with you that Xenon 2 is a bad game. However, there's still something I want to point out.

Originally Posted by Hewitson

No. You're wrong. Play a few Japanese shoot em ups from the same era. Thunder Force IV, for example.

Pointing to a game widely considered one of the (if not the very) best games of it's genre ever released (certainly when looking at the 16 bit era) is hardly a fair way to determine if the game you're comparing it to is a "good game".

Well, IMHO anyway.

[skan]

I like it. Period.
And my opinion has the very same f*ucking weight as yours. Period.

That said and back on topic, some interesting thoughts have emerged from the thread, makes me wonder if stable 25fps framerate was really impossible to achieve or within reach with just some different approach.

[Tigerskunk]

Originally Posted by skan

I like it. Period.
And my opinion has the very same f*ucking weight as yours. Period.

Off course...

[Galahad/FLT]

I personally don't think the A500 could manage a steady 25frames with the design brief of Xenon 2.

I think if they had reduced the weaponry a little, it could still have been a hectic game and had a lot going on, but the design brief for Xenon 2 simply wouldn't allow it.

Sure, in a screenshot, having all that shit on screen looks impressive..... less so when its in motion.

I think if the Bitmaps hadn't been so adventurous, less could have been more.

[Tigerskunk]

Originally Posted by Galahad/FLT

Sure, in a screenshot, having all that shit on screen looks impressive.....

Xenon2 looks like it has been made with the idea in mind, that is should look impressive on screenshots.

Which it did.
You almost could not believe this game is real back in the day when you saw advertisements of it.

[skan]

Originally Posted by Steril707

Off course...

That was not addressed to you mate ...and I know you hate X2 just because of the alien shop anyway!

Originally Posted by Galahad/FLT

I personally don't think the A500 could manage a steady 25frames with the design brief of Xenon 2.

I think if they had reduced the weaponry a little, it could still have been a hectic game and had a lot going on, but the design brief for Xenon 2 simply wouldn't allow it.

Sure, in a screenshot, having all that shit on screen looks impressive..... less so when its in motion.

I think if the Bitmaps hadn't been so adventurous, less could have been more.

Good point. Yeah, less could have been more indeed!

[roondar]

Originally Posted by skan

And my opinion has the very same f*ucking weight as yours. Period.

This is my view as well, to each their own

That said and back on topic, some interesting thoughts have emerged from the thread, makes me wonder if stable 25fps framerate was really impossible to achieve or within reach with just some different approach.

Originally Posted by Galahad/FLT

I personally don't think the A500 could manage a steady 25frames with the design brief of Xenon 2.

I'd agree with Galahad that a 25FPS Xenon 2 (with everything else remaining as is) would be an uphill battle for the Amiga.
Removing the background layer or going Dual Playfield (with a 3/2 split) and properly using hardware sprites (for all the bullets if possible) should help a lot, though. But overall it'd probably have been better for steady FPS if the limits of the various platforms had been taken into account in the design of the game.

Especially for the Amiga version as the hardware is different enough compared to other platforms to necessitate using Amiga specific solutions to get the best possible results.

[skan]

Originally Posted by roondar

This is my view as well, to each their own

Indeed, but I admit I'm biased 'coz I'm a BitmapBros fanboi ever since!

Originally Posted by roondar

Especially for the Amiga version as the hardware is different enough compared to other platforms to necessitate using Amiga specific solutions to get the best possible results.

Yeah, I'm a fanboi, but I can see the wasted chance.