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[Turrican]

If you're Manfred Trenz, sure. One of the very best technical coders of his day, and factoring that in his original C64 version of Turrican is actually even more impressive considering the hardware limitations.

Generally though, you're severely understimating the magnitude of difficulty.

The "cheap" way of doing scrolling on the Amiga uses screen pointer manipulation. Its fast, but not free because you have to do the edge-updates using regular blits. The edge updates uses fake tiles, because you are always writing to bitmap UNLIKE either MegaDrive or SNES which had actual mapped tile playfields.

The difference being that changing a single 16x16 pixel tile on the consoles involved writing a single word, on the Amiga that was 16 blitter writes per bitplane, so 16x3 per tile, per layer assuming your configuration is 2x 8colour dual playfields. So, 48x slower plus the additional overhead of tracking write position (no DMA-delay to help you out) as the display area drifts according to "map" position, and the additional overhead of all those bitplanes eating into cpu overhead.

Also, to stop the edge-update eating into frame-time you have to carefully manage the screen scrolling to limit scenarios where you're forced to update both a horizontal and a vertical edge at the same time, and allow you to pre-cache your new data into a single blit to lower cpu-cost.

Trust me, I've written scroll routines for both, and Amiga is vastly more complicated.

I don't think anyone ever multiplexed sprites per se on Amiga either; traditional multiplexors like on c64 essentially were used to put more "actor" objects on-screen (baddies). On the Amiga each sprite was effectively too small to be used for much as enemies tended to be larger in terms of pixel dimensions and all multiplexors are hamstrung by the hardware setting finite limits on how many can be drawn in the same horizontal band,

On the Amiga, ironically they more often tended to be used by force-loading data into the registers in a repeating pattern to create an additional fake scrolling layer. The only snag being doing that essentially locked out the CPU for the duration of its display.

Leander/Galahad is a good example of all the techniques I've mentioned. Jon (Burton) was an extremely good 68k coder, although to be fair a lot of his tricks were straight lifts of known demo-scene techniques which is why they tended to have quite specific limitations in application.

Which in the end, is kinda the crux of the matter. If you have to dig deep into your grab-bag of tricks and do a bunch of very technical code to do basic stuff like drawing objects and scrolling the screen, it leaves you less time to work on the rest of the game. It even affects the design because., for instance, the pointer-scroll technique while way quicker than doing it the orthodox way (full screen copy and shift, or redraw every tile on update) means you can't wrap your scrolling playfield around on itself.

Coming from the Amiga, Megadrive/Genesis was easy mode. Night and day different. The 68000 was even clocked higher on top of the entire raster update basically only requiring you to prime the VDP with data and set it to trigger DMA download on VBlank... It was cake by comparison.

Manfred Trenz only wrote the C64 Turrican games which worked fundamentally different from the Amiga ones since the C64 was comparatively relatively easy for tile scrolling (not to downplay the brilliance that the C64 Turrican versions were). He never made a game for the Amiga and only programmed the intro screen of Turrican 1 on it. Factor 5 did the Amiga (and Atari ST) Turricans. And yes, of course the Amiga was hard for these types of action games. Just as the Megadrive/Genesis was for sprite and playfield rotation and scaling which very few really good teams pulled off nonetheless, Factor 5 and Traveler’s Tales included.

 

[Clear]

Many Amiga action games used sprite multiplexing, especially for bullets. It could be done horizontally, for instance in Jim Power



or even easier vertically in something like Mega Typhoon



And if you're skeptical of the power of Amiga sprites on AGA just look at this upcoming game

You're cherry-picking some real edge-case examples to make your point! All I said was most games didn't use sprites, as much as anything because you couldn't do everything with them, whereas general purpose Bob code was a lot more flexible and could, albeit at cost.

The reality was that by '92-'93 most of the better 68k coders had (been) moved onto the consoles as the market for commercial Amiga games was in such poor shape, with many of them moving onto other systems (like Playstation) within a couple of years after that when the 3D revolution happened .

Basically when Doom came out in '93... we all knew the writing was on the wall!

T Turrican

The reason why "Turrican" is so highly rated technically is that it does the hardest stuff possible without resorting to tricks like VSP. A full-screen colour scroll without VSP is pretty painful because you have to split it up into multiple sections as you cannot double-buffer the colour ram update, and without a ram expansion you cannot fully unroll the copy loops without ending up severely short on memory.
These days people just use VSP (basically exploiting a bug in the VIC chip to create DMA-delay, which is what consoles do by design) and simply assume that the hardware can handle it without issues; whereas back when it was first discovered publishers wouldn't touch a game using the technique out of fear that it just crashed some systems.

 

[lionagony]

You're cherry-picking some real edge-case examples to make your point! All I said was most games didn't use sprites, as much as anything because you couldn't do everything with them, whereas general purpose Bob code was a lot more flexible and could, albeit at cost.

Yes, it's true that most things were done with Bobs but I wouldn't say my examples are edge cases, there are a large number of Amiga games that make good use of the sprite system, it would have been great if there were more than 8 sprites but having them be so tall and being able to multiplex gave them power. On AGA having 64 pixel wide sprites is very useful.

The reality was that by '92-'93 most of the better 68k coders had (been) moved onto the consoles as the market for commercial Amiga games was in such poor shape, with many of them moving onto other systems (like Playstation) within a couple of years after that when the 3D revolution happened .

I actually think many of the best Amiga games came out in 93-94. Lionheart, Ruff N Tumble, Chaos Engine, Alien Breed Tower Assault, Mr Nutz, Kid Chaos, Marvin's Marvelous Adventure etc. etc.

Basically when Doom came out in '93... we all knew the writing was on the wall!

Although Doom was the very end of 93 in December. The Amiga wasn't greatly equipped for 3D but personally I love 2D games much more. And maybe the Amiga wasn't so bad for 3D after all, just look at Grind