Does it make sense to use BOBs on a 030?

[Quagliarulo]

Hello, let's suppose you want to make a game such as Final Fight, targeted at AGA and fast 030 CPUs. Would you use the blitter or rather the CPU to display the fighters?

In general, given the same type of game, what is the least powerful CPU that would make you choose not to use the blitter?

I know that the answer depends on a number of other factors, but I'd like to read your opinions.

[AmigaHope]

Short answer: Anytime I have real fast RAM.

Long answer: Depends on colors/resolution. If I'm working in a lores screenmode in best fetchmode there's always some free time left over for the blitter to do *SOMETHING*. The faster your CPU gets, the more it's held back by bandwidth to chipmem. You should always max out what the blitter can do without stealing cycles first, then do the rest with the CPU copying from fast memory. The blitter is crippled by being essentially the old ECS Agnus blitter, but it has the advantage of having access to DMA time that the CPU doesn't.

[jotd]

don't forget that the blitter not only copies but shifts & masks.

[Old_Bob]

Originally Posted by jotd

don't forget that the blitter not only copies but shifts & masks.

Very much this!!

If you're doing everything with the CPU, you'll need either preshifted copies of each frame of graphics (ZX Spectrum style ) or you'll have to shift all the bits in real time as you're drawing them.

If you have enough Fast RAM for the 16 copies of all the graphics and mask bits you'll need, then even the stock 14mhz CPU inside an A1200 should beat the blitter by a decent margin.

And, you can always use the blitter as well to have even more going on screen.

B

[Quagliarulo]

Can A1200s and A4000s have any slow RAM fitted into them?
Which machines can?

[AmigaHope]

Originally Posted by Quagliarulo

Can A1200s and A4000s have any slow RAM fitted into them?
Which machines can?

The only machines that support true slow ram without hacks are The A500 and OCS A2000. You might consider A600 and A1200 PCMCIA RAM to be slow ram since it goes through Gayle, though I don't know if Gayle lives entirely on the chip/slow bus like Gary does on A500/A2000, so I don't know if DMA slots block PCMCIA access (which would make it true slow ram, even if the ram is natively slower than chip RAM anyway)

Could you fit slow RAM by wiring it directly into FatGary/Gayle? Probably -- but why would you do that?