Shadow of the beast 2/3 technical breakdown?

[Adrian Browne]

Has there ever been an in depth analysis of sotb 2 or 3 from a technical point of view? Or are they not that remarkable? I know codetapper did a deep dive of part 1.

I understand beast 2 uses dual playfield mode and maybe 16 colours. I assume the pink graduated background was done with copper. Beast 3 has some impressively big boss sprites too.
Any thoughts or info on these games?

[alain.treesong]

Hello Adrian,

I had a look to shadow of the beast 3 some monthes (or perhaps years) ago.
I think this game is probably one the best game in a technical and artistic point of view.

As the game has also a good gameplay and is specific to the Amiga (no other existing version on other platfforms I think) it is certainly one of the masterpiece of the A500.

There are four "worlds". If I have good memory, one at least (the castle) is in half bright mode (64 colors) and others are un dual playfield.

The main character and his shuriken are sprites.

The mountains in the back are an animation : we have the impression that there are 2 planes of mountains and therefore that the screen is in quad playfield but the two planes of mountains are a same animation. It is very well done.

The option screen of the game is in dual playfied : the platforms and the ladders are in 8 colors (!). The front of the screen are the title and the menu info. I will check that with winuae and will confirm (or not) these first data.

[amuleth]

Maybe this can help http://amr.abime.net/review_38412

[alain.treesong]

So I take the great winuae to check what I have said. Globally What I spoke about was accurate.

If we consider the option screen :


The main character runs and climb ladders. There is a far backgound with clouds and mountains. The floor is made of a lot of parallax scrollings
The foreground is made of 4 rotating discs, one for each level/world of the game. In one word : "Beautiful"

If we disable the bitplanes and the sprites, it gives that :

So a nice raster made with the copper that change color register.

If we enable only the sprites, it gives that:

As we can see, the clouds and far mountains are made of sprites. Like the main character, the red arrow and element of the panel. Nice additional raster in the life counters. So the "dual playfield" of the mountain is in fact an animation as I said in my previous post.

If we enable only the 6 bitpalnes of Amiga OCS, it gives that:

So the scene is in dual playfield mode :
- the background playfield (3 bitplanes) contain ladders and platforms. Only 7 colors. Whaow ! I suppose low part of the screen (parallax flour) is done using registers handled by the copper.
- the foreground playfield (3 bitplanes) contain the 4 rotating disc. I suppose they are moved with blitter

Here is only the background playfield enabled (with sprites enabled):


Here is only the foreground playfied enabled (with sprites enabled):


Another example if we disable some sprites :

We can see tat part of mountains and the hero have disappeared.

So a nice screen with a great mastery of the ocs.

[rothers]

It's a really strange use of dual playfield. I guess they had their reasons for using the front layer for bobs?

I do wish more games used sprites for a fake dual playfield layer. It's so easy to add and gives games that 16bit feel.

Edit, actually thinking about it perhaps using 8+8 saved on memory and disk space in terms of compression.

[alain.treesong]

In fact the first playfield in the option screen allows to set the title of the game or a list of option screens :


Some levels use also the dual playfield mode.
For example the level 1 (the forest) :


If we remove all the bitplanes, keeping only the sprites :

There is only remaining the far "dual fields" mountains

If we enable only the first field (and the sprites):


If we enable only the back field (and the sprites):

We can see that the floor (with a lot of scrolls) is defined in the back field

The second level (the castle) doesn't use the dual playfield but the half bright mode (so the 6 bitplanes like in the dual playfields but differently). A multi directionnal scroll platform game in half bright and remaining at 50 fps is not common :


We can disable for exemple 2 bitplanes (it remains 4 displayed bitplanes) :


EDIT : in fact the castle level is not in EHB but also in dual playfield with exceptionnal graphics. Some later messages spoke about that :-)

[Pyromania]

Great thread!

[jotd]

dual playfield is handy to avoid "cookie cut" and "background restore" blitter operations that cost a lot of bandwidth. I suppose some games which don't scroll use it too.

[alain.treesong]

Example where dual playfield mode is used for performance reason and not to allow two parallel scrolling fields is Shadow fighter (some others threads about SF2 and others detailled this)

[Adrian Browne]

Thanks for the very useful information Alain. It's fascinating stuff. Beast 3 seems to use different tricks for different levels then. Doing the mountains as animation - I will remember that. I have the dream of making a Shadow of the beast style game on amiga; probably something technically simpler I guess. Beast 3 is a beautiful game though perhaps the art style is somewhat inconsistent from level to level- or the quality at least.

[ Show youtube player ] This large and animated boss is impressive-

[rothers]

I realised yesterday after posting the dualplayfield set up will help with collision detection.

[alain.treesong]

@Adrian
As you can see, near 6:44 (with the big red boss) there is no front field anymore.
So I guess that the boss is alone in the front field. It allows performance tricks. Other games use this trick (Jim power for example)

@rothers
Yes the hardware allows to manage collision detection with bitplanes and sprites for example ($DFF00E). Sometines more performance is get by using box and not the hardware registers. It depends.

[Foebane]

As we can see, the clouds and far mountains are made of sprites.

How is that possible, if they fill the full width of the screen and they're all on the same Y axis?

When I got my Amiga in 1990, I was amazed at the smoothness of SOTB2 and thought that the entire moving playfield was "multiplexing" sprites. Of course, this was before I knew anything about the Amiga and my opinion about any of it was vastly inflated.

But I learned that Amiga sprites are like Atari 8-Bit sprites: infinite height, but limited in the X-axis. And multiplexing is only good for repositioning a sprite as the screen is drawn, but I'm baffled as to how sprites can fill the width of a screen in the same Y-position, if the total number of pixels is 8x16 (8 sprites @ 16 pixels width).

[Galahad/FLT]

Originally Posted by Foebane

How is that possible, if they fill the full width of the screen and they're all on the same Y axis?

When I got my Amiga in 1990, I was amazed at the smoothness of SOTB2 and thought that the entire moving playfield was "multiplexing" sprites. Of course, this was before I knew anything about the Amiga and my opinion about any of it was vastly inflated.

But I learned that Amiga sprites are like Atari 8-Bit sprites: infinite height, but limited in the X-axis. And multiplexing is only good for repositioning a sprite as the screen is drawn, but I'm baffled as to how sprites can fill the width of a screen in the same Y-position, if the total number of pixels is 8x16 (8 sprites @ 16 pixels width).

Part of the reason is that Beast 3 isn't full width screen, most games are at least 320 pixels width, Beast 3 is less than that.

[alain.treesong]

Good examples of the sprite backgound trick can be found here :
https://codetapper.com/amiga/sprite-...rian-the-lion/
https://codetapper.com/amiga/sprite-tricks/jim-power/

We can also remark that the main SOTB3 character is always at the same place, under the mountains. :-)

[Foebane]

Originally Posted by alain.treesong

Good examples of the sprite backgound trick can be found here :
https://codetapper.com/amiga/sprite-...rian-the-lion/
https://codetapper.com/amiga/sprite-tricks/jim-power/

Of course, the Copper. Is there no end to the tricks you can perform, Amiga?

[Adrian Browne]

Originally Posted by alain.treesong

@Adrian
As you can see, near 6:44 (with the big red boss) there is no front field anymore.
So I guess that the boss is alone in the front field. It allows performance tricks. Other games use this trick (Jim power for example)

@rothers
Yes the hardware allows to manage collision detection with bitplanes and sprites for example ($DFF00E). Sometines more performance is get by using box and not the hardware registers. It depends.

Ah ok- no parallax or other layers so then a big enemy sprite can be moved onscreen. Cool

[Adrian Browne]

So what resolution is this game in? 320 x 256?

[vulture]

iirc 288*192 and it's ntsc compatible

[roondar]

Fascinating stuff. I'd never have guessed that the castle level was in EHB.